Limbach (LMB) 10-Q 14 Aug 19 2019 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2019	Aug. 14, 2019
Document and Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Entity Registrant Name	Limbach Holdings, Inc.
Entity Central Index Key	0001606163
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Trading Symbol	LMB
Entity Current Reporting Status	Yes
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		7,643,133

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Current assets
Cash and cash equivalents	$ 1,011	$ 1,619
Restricted cash	113	113
Accounts receivable, net	142,761	135,687
Costs and estimated earnings in excess of billings on uncompleted contracts	36,030	32,698
Other current assets (Note 14)	4,637	34,869
Total current assets	184,552	204,986
Property and equipment, net of accumulated depreciation of $14.1 million and $11.8 million at June 30, 2019 and December 31, 2018, respectively	20,758	20,527
Intangible assets, net	12,603	12,953
Goodwill	10,488	10,488
Deferred tax asset	4,170	4,409
Other assets	798	271
Total assets	233,369	253,634
Current liabilities
Current portion of long-term debt	2,173	3,141
Accounts payable, including retainage	69,702	74,353
Billings in excess of costs and estimated earnings on uncompleted contracts	46,536	50,843
Accrued income taxes	10	0
Accrued expenses and other current liabilities (Note 14)	24,575	53,801
Total current liabilities	142,996	182,138
Long-term debt	39,983	23,614
Other long-term liabilities	2,498	1,514
Total liabilities	185,477	207,266
Commitments and contingencies (Note 14)
Redeemable convertible preferred stock, net, par value $0.0001, 1,000,000 shares authorized, no shares issued and outstanding at June 30, 2019 or December 31, 2018	0	0
STOCKHOLDERS' EQUITY
Common stock, $0.0001 par value; 100,000,000 shares authorized, 7,643,133 issued and outstanding at June 30, 2019 and 7,592,911 at December 31, 2018	1	1
Additional paid-in capital	55,673	54,791
Accumulated deficit	(7,782)	(8,424)
Total stockholders' equity	47,892	46,368
Total liabilities and stockholders' equity	$ 233,369	$ 253,634

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	$ 14.1	$ 11.8
Common Stock, Par or Stated Value Per Share	$ 0.0001	$ 0.0001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares, issued	7,643,133	7,592,911
Common stock, shares, outstanding	7,643,133	7,592,911
Redeemable Preferred Stock [Member]
Temporary Equity, Par or Stated Value Per Share	$ 0.0001	$ 0.0001
Temporary Equity, Shares Authorized	1,000,000	1,000,000
Temporary Equity, Shares Issued	0	0
Temporary Equity, Shares Outstanding	0	0

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Condensed Consolidated Statements of Operations
Revenue	$ 132,753	$ 139,531	$ 266,704	$ 260,080
Cost of revenue	115,352	123,733	229,270	230,995
Gross profit	17,401	15,798	37,434	29,085
Operating expenses:
Selling, general and administrative expenses	17,079	13,685	33,124	29,351
Amortization of intangibles	175	336	350	671
Total operating expenses	17,254	14,021	33,474	30,022
Operating income (loss)	147	1,777	3,960	(937)
Other income (expenses):
Interest expense, net	(1,597)	(799)	(2,430)	(1,568)
Gain on disposition of property and equipment	9	24	21	40
Loss on debt extinguishment	(513)		(513)
Loss on change in fair value of warrant liability	(103)		(103)
Total other expenses	(2,204)	(775)	(3,025)	(1,528)
Income (loss) before income taxes	(2,057)	1,002	935	(2,465)
Income tax provision (benefit)	(553)	293	293	(750)
Net income (loss)	(1,504)	709	642	(1,715)
Dividends on cumulative redeemable convertible preferred stock	0	0	0	(113)
Premium paid on partial preferred redemption	0	0	0	2,219
Net income (loss) attributable to Limbach Holdings, Inc. common stockholders	$ (1,504)	$ 709	$ 642	$ (3,821)
Basic earnings (loss) per share for common stock:
Net earnings (loss) attributable to Limbach Holdings, Inc. common stockholders	$ (0.20)	$ 0.09	$ 0.08	$ (0.51)
Diluted earnings (loss) per share for common stock:
Net earnings (loss) attributable to Limbach Holdings, Inc. common stockholders	$ (0.20)	$ 0.09	$ 0.08	$ (0.51)
Weighted average number of shares outstanding:
Basic	7,643,133	7,542,503	7,643,133	7,541,965
Diluted	7,643,133	7,807,768	7,717,484	7,541,965

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock	Additional Paid in Capital [Member]	Accumulated deficit [Member]	Total
Beginning Balance at Dec. 31, 2017	$ 1	$ 54,738	$ (6,579)	$ 48,160
Beginning Balance (in shares) at Dec. 31, 2017	7,504,133
Dividends on redeemable convertible preferred stock	$ 0	113	0	113
Premium paid on redemption of redeemable convertible preferred stock	0	(2,219)		(2,219)
Stock-based compensation	0	467	0	467
Shares issued related to vested restricted stock units	$ 0	0	0	0
Shares issued related to vested restricted stock units (in shares)	27,489
Exercise of warrants	$ 0	0	0	0
Exercise of warrants (in shares)	10,627
Net income (loss)	$ 0	0	(2,424)	(2,424)
Ending Balance at Mar. 31, 2018	$ 1	53,099	(9,003)	44,097
Ending Balance (in shares) at Mar. 31, 2018	7,542,249
Beginning Balance at Dec. 31, 2017	$ 1	54,738	(6,579)	48,160
Beginning Balance (in shares) at Dec. 31, 2017	7,504,133
Net income (loss)				(1,715)
Ending Balance at Jun. 30, 2018	$ 1	53,753	(8,294)	45,460
Ending Balance (in shares) at Jun. 30, 2018	7,542,249
Beginning Balance at Mar. 31, 2018	$ 1	53,099	(9,003)	44,097
Beginning Balance (in shares) at Mar. 31, 2018	7,542,249
Stock-based compensation	$ 0	654		654
Net income (loss)	0	0	709	709
Ending Balance at Jun. 30, 2018	$ 1	53,753	(8,294)	45,460
Ending Balance (in shares) at Jun. 30, 2018	7,542,249
Beginning Balance at Dec. 31, 2018	$ 1	54,791	(8,424)	46,368
Beginning Balance (in shares) at Dec. 31, 2018	7,592,911
Stock-based compensation	$ 0	367	0	367
Shares issued related to vested restricted stock units	$ 0	0	0	0
Shares issued related to vested restricted stock units (in shares)	50,222
Net income (loss)	$ 0	0	2,146	2,146
Ending Balance at Mar. 31, 2019	$ 1	55,158	(6,278)	48,881
Ending Balance (in shares) at Mar. 31, 2019	7,643,133
Beginning Balance at Dec. 31, 2018	$ 1	54,791	(8,424)	46,368
Beginning Balance (in shares) at Dec. 31, 2018	7,592,911
Net income (loss)				642
Ending Balance at Jun. 30, 2019	$ 1	55,673	(7,782)	47,892
Ending Balance (in shares) at Jun. 30, 2019	7,643,133
Beginning Balance at Mar. 31, 2019	$ 1	55,158	(6,278)	48,881
Beginning Balance (in shares) at Mar. 31, 2019	7,643,133
Stock-based compensation	$ 0	515	0	515
Net income (loss)	0	0	(1,504)	(1,504)
Ending Balance at Jun. 30, 2019	$ 1	$ 55,673	$ (7,782)	$ 47,892
Ending Balance (in shares) at Jun. 30, 2019	7,643,133

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018
Cash flows from operating activities:
Net income (loss)		$ 642	$ (1,715)
Adjustments to reconcile net income (loss) to cash provided (used in) by operating activities:
Depreciation and amortization		2,873	2,798
Provision for doubtful accounts		33	47
Stock-based compensation expense		882	1,121
Amortization of debt discount and issuance costs		510	144
Deferred income tax provision (benefit)		239	(750)
Loss on debt extinguishment		513
Change in fair value of warrant liability		103
Gain on sale of property and equipment		(21)	(40)
Changes in operating assets and liabilities:
(Increase) decrease in accounts receivable		(7,107)	(8,060)
(Increase) decrease in costs and estimated earnings in excess of billings on uncompleted contracts		(3,332)	283
(Increase) decrease in other current assets	[1]	30,138	(688)
(Increase) decrease in other assets			(289)
Increase (decrease) in accounts payable		(4,651)	(6,017)
Increase (decrease) in billings in excess of costs and estimated earnings on uncompleted contracts		(4,307)	15,407
(Increase) decrease in prepaid income taxes	[1]	101	(706)
Increase (decrease) in accrued taxes payable			(2,222)
Increase (decrease) in accrued expenses and other current liabilities		(32,190)	1,112
Increase (decrease) in other long-term liabilities		(87)	255
Net cash (used in) provided by operating activities		(15,661)	680
Cash flows from investing activities:
Proceeds from sale of property and equipment		77	123
Advances to joint ventures		1	0
Purchase of property and equipment		(1,229)	(2,117)
Net cash used in investing activities		(1,151)	(1,994)
Cash flows from financing activities:
Increase in bank overdrafts		2,783	4,869
Proceeds from 2019 Refinancing Term Loan, net of debt discount		38,643
Warrants issued in conjunction with the 2019 Refinancing Term Loan		969
Embedded derivative associated with the 2019 Refinancing Term Loan		388
Proceeds from Bridge Term Loan		0	10,000
Payments on Bridge Term Loan		(7,736)	(1,764)
Payments on capital leases		(1,140)	(957)
Convertible preferred stock redeemed		0	(9,191)
Convertible preferred stock dividends paid		0	(875)
Payments of debt issue costs		(3,339)	0
Taxes paid related to net-share settlement of equity awards		(29)	(83)
Net cash provided by financing activities		16,204	944
Increase (decrease) in cash, cash equivalents and restricted cash		(608)	(370)
Cash, cash equivalents and restricted cash, beginning of period		1,732	739
Cash, cash equivalents and restricted cash, end of period		1,124	369
Noncash investing and financing transactions:
Property and equipment acquired financed with capital leases		1,581	1,521
Interest paid		1,621	1,184
Credit Agreement term loan
Cash flows from financing activities:
Repayments of Long-term Lines of Credit		(14,335)	(1,500)
Credit Agreement revolver
Cash flows from financing activities:
Proceeds from Long-term Lines of Credit		17,500	67,039
Repayments of Long-term Lines of Credit		(17,500)	$ (66,594)
2019 Revolving Credit Facility
Cash flows from financing activities:
Proceeds from Long-term Lines of Credit		7,500
Repayments of Long-term Lines of Credit		$ (7,500)
[1]	The prior period has been reclassified to conform to the current period presentation.

Organization and Plan of Busine

Organization and Plan of Business Operations	6 Months Ended
	Jun. 30, 2019
Organization and Plan of Business Operations
Organization and Plan of Business Operations	Note 1 – Organization and Plan of Business Operations Limbach Holdings, Inc. (the “Company” or “we”) is a Delaware corporation headquartered in Pittsburgh, Pennsylvania. The Company’s Condensed Consolidated Financial Statements include the accounts of Limbach Holdings, Inc. and its wholly owned subsidiaries, including Limbach Holdings LLC (“LHLLC”), Limbach Facility Services LLC (“LFS”), Limbach Company LLC, Limbach Company LP, Harper Limbach LLC (“Harper”) and Harper Limbach Construction LLC. We operate our business in two segments, (i) Construction, in which we generally manage large construction or renovation projects that involve primarily heating, ventilation, and air conditioning (“HVAC”), plumbing or electrical services, and (ii) Service, in which we provide maintenance or service primarily on HVAC, plumbing or electrical systems. This work is primarily performed under fixed price, modified fixed price, and time and material contracts over periods of typically less than two years. The Company’s customers operate in several different industries, including healthcare, education, government, commercial, manufacturing, mission critical, entertainment, and leisure. The Company operates primarily in the Northeast, Mid-Atlantic, Southeast, Midwest, and Southwestern regions of the United States. The Company was originally incorporated as a special purpose acquisition company, formed for the purpose of effecting a merger, equity interest exchange, asset acquisition, stock purchase, reorganization or similar business combination with one or more businesses. On July 20, 2016, the Company consummated a business combination (the “Business Combination”) whereby it acquired all of the outstanding equity of LHLLC. In connection with the closing of the Business Combination, the Company changed its name from 1347 Capital Corp. (“1347 Capital”) to Limbach Holdings, Inc. Emerging Growth Company Section 102(b)(1) of the Jumpstart Our Business Startups Act (the “JOBS Act”) exempts emerging growth companies from being required to comply with new or revised financial accounting standards until private companies (that is, those that have not had a registration statement under the Securities Act of 1933, as amended, declared effective or do not have a class of securities registered under the Securities Exchange Act of 1934, as amended (the “Exchange Act”)) are required to comply with the new or revised financial accounting standards. The JOBS Act provides that a company can elect to opt out of the extended transition period and comply with the requirements that apply to non-emerging growth companies but any such election to opt out is irrevocable. The Company has elected not to opt out of such extended transition period, which means that when a standard is issued or revised and it has different application dates for public or private companies, the Company, as an emerging growth company, can adopt the new or revised standard at the time private companies adopt the new or revised standard. This may make comparison of the Company’s financial statements with another public company, which is neither an emerging growth company nor an emerging growth company which has opted out of using the extended transition period, difficult or impossible because of the potential differences in accounting standards used.

Significant Accounting Policies

Significant Accounting Policies	6 Months Ended
	Jun. 30, 2019
Significant Accounting Policies
Significant Accounting Policies	Note 2 – Significant Accounting Policies Basis of Presentation Condensed Financial Statements The accompanying unaudited Condensed Consolidated Financial Statements have been prepared in accordance with instructions to the Quarterly Report on Form 10‑Q and Rule 8‑03 of Regulation S-X for smaller reporting companies. Consequently, certain information and note disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) have been condensed or omitted pursuant to those rules and regulations, although the Company believes that the disclosures made are adequate to make the information not misleading. Readers of this report should refer to the consolidated financial statements and the notes thereto included in our latest Annual Report on Form 10‑K filed with the Securities and Exchange Commission (the “SEC”) on April 15, 2019. Unaudited Interim Financial Information The accompanying interim Condensed Consolidated Balance Sheets, Condensed Consolidated Statements of Operations, Condensed Consolidated Statements of Stockholders’ Equity and Condensed Consolidated Statements of Cash Flows for the periods presented are unaudited. Also, within the notes to the Condensed Consolidated Financial Statements, we have included unaudited information for these interim periods. These unaudited interim Condensed Consolidated Financial Statements have been prepared in accordance with GAAP. In our opinion, the accompanying unaudited Condensed Consolidated Financial Statements contain all normal and recurring adjustments necessary for a fair statement of the Company’s financial position as of June 30, 2019, its results of operations for the three and six months ended June 30, 2019, and its cash flows for the six months ended June 30, 2019. The results for the three and six months ended June 30, 2019 are not necessarily indicative of the results to be expected for the year ending December 31, 2019. The Condensed Consolidated Balance Sheet as of December 31, 2018 was derived from our audited financial statements filed with the SEC on April 15, 2019, but is presented as condensed and does not contain all of the footnote disclosures from the annual financial statements. Revenues and Cost Recognition Revenues from fixed price and modified fixed price contracts are recognized on the percentage-of-completion method, measured by the relationship of total cost incurred to total estimated contract costs (cost-to-cost method). Contract revenue for long-term construction contracts is based upon management’s estimates of contract values at completion, including revenue for additional work on which the contract value has not been finalized (claims and unapproved change orders) but is considered probable. Changes in job performance, job conditions, and estimated profitability, including those arising from contract penalty provisions and final contract settlements, may result in revisions to estimated costs and income, and are recognized in the period in which the revisions are determined. Provisions for estimated losses on uncompleted contracts are recognized in the period in which such losses are determined. Contract costs include direct labor, material, and subcontractor costs, and those indirect costs related to contract performance, such as indirect labor, supplies, tools, repairs, depreciation, and insurance. Total estimated contract costs are based upon management’s current estimate of total costs at completion. There are two basic types of service contracts: fixed price service contracts which are signed in advance for maintenance, repair and retrofit work over a period of typically one year, and service contracts not signed in advance for similar maintenance, repair and retrofit work performed on an as-needed basis. Fixed price service contracts are generally performed evenly over the contract period, and accordingly, revenue is recognized on a pro rata basis over the life of the contract. Revenues derived from other service contracts are recognized when the services are performed. Expenses related to all service contracts are recognized as services are provided. Costs and estimated earnings in excess of billings on uncompleted contracts reflected in the Condensed Consolidated Financial Statements arise when revenues have been recognized but the amounts cannot be billed under the terms of the contracts. Also included in costs and estimated earnings in excess of billings on uncompleted contracts are amounts the Company seeks or will seek to collect from customers or others for errors or changes in contract specifications or design, contract change orders in dispute or unapproved as to scope and price, or other customer-related causes of unanticipated additional contract costs (claims and unapproved change orders). Claims and unapproved change orders are recorded at estimated net realizable value when realization is probable and can be reasonably estimated. No profit is recognized on the construction costs incurred in connection with claim amounts. Claims and unapproved change orders made by the Company may involve negotiation and, in rare cases, litigation. Claims and unapproved change orders involve the use of estimates, and it is reasonably possible that revisions to the estimated recoverable amounts of recorded claims and unapproved change orders may be made in the near term. Claims against the Company are recognized when a loss is considered probable and amounts are reasonably determinable. Billings in excess of costs and estimated earnings on uncompleted contracts represent billings in excess of revenues recognized. In accordance with industry practice, we classify as current all assets and liabilities relating to the performance of contracts. The terms of our contracts generally range from six months to two years. Selling, general, and administrative costs are charged to expense as incurred. Bidding and proposal costs are also recognized as an expense in the period in which such amounts are incurred. Reclassifications and Adjustments Certain reclassifications of prior periods’ data have been made to conform to the current period presentation. The Company reclassified this prior period data as a result of the retrospective adoption on January 1, 2019 of Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) 2016‑18, “Statement of Cash Flows: Restricted Cash.” The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the Company’s Condensed Consolidated Balance Sheets that sum to the total of the same amounts shown in the Condensed Consolidated Statement of Cash Flows: (in thousands) June 30, 2019 December 31, 2018 June 30, 2018 December 31, 2017 Cash and cash equivalents $ 1,011 $ 1,619 $ 256 $ 626 Restricted cash 113 113 113 113 Total cash, cash equivalents and restricted cash $ 1,124 $ 1,732 $ 369 $ 739

Accounting Standards

Accounting Standards	6 Months Ended
	Jun. 30, 2019
Accounting Standards
Accounting Standards	Note 3 – Accounting Standards Recent Accounting Pronouncements The effective dates shown in the following pronouncements are private company effective dates, based upon the Company’s election to conform to private company effective dates based on the relief provided to Emerging Growth Companies (“EGC”) under the JOBS Act. In May 2014, the FASB issued ASU 2014‑09, “Revenue from Contracts with Customers—Topic 606,” which supersedes the revenue recognition requirements in FASB Accounting Standard Codification (“ASC”) 605. The new guidance established principles for reporting revenue and cash flows arising from an entity’s contracts with customers. This new revenue recognition standard will replace all of the recognition guidance within GAAP. This guidance was deferred by ASU 2015‑14, “Revenue from Contracts with Customers (Topic 606): Deferral of the effective date, issued by the FASB in August 2015,” which deferred the effective date of ASU 2014‑09 from annual and interim periods beginning after December 15, 2017 to annual and interim periods beginning after December 15, 2018. In March 2016, the FASB issued ASU 2016‑08, “Revenue from Contracts with Customers: Principal versus Agent Considerations,” which further clarifies the implementation guidance in ASU 2014‑09. In April 2016, the FASB issued ASU 2016‑10, “Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing,” to expand the guidance on identifying performance obligations and licensing within ASU 2014‑09. In May 2016, the FASB issued ASU 2016‑12, “Revenues from Contracts with Customers: Narrow-Scope Improvements and Practical Expedients,” which amends the guidance in the new revenue standard on collectability, noncash consideration, presentation of sales tax, and transition. The amendments are intended to address implementation issues that were raised by stakeholders and provide additional practical expedients to reduce the cost and complexity of applying the new revenue standard. The guidance can be applied on a full retrospective or modified retrospective basis whereby the entity records a cumulative effect of initially applying this update at the date of initial application. In December 2016, the FASB issued ASU 2016‑20, “Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers” intended to clarify the codification or to correct unintended application of the guidance which clarifies the definition of loan guarantee fees, what should be considered in contract costs impairment testing, a requirement that provisions for losses on construction-type and production-type contracts be determined at the least at the contract level, exclusion of insurance contracts from scope, specific disclosures regarding remaining performance obligations, disclosure of prior-period performance obligations and gives an example of contract modifications. These standards are required to be implemented by the Company for its fiscal year 2019 Consolidated Financial Statements and for interim periods beginning in fiscal year 2020. We have made progress in evaluating the impact of the new pronouncement on our contracts, including identifying potential differences that will result from applying the new guidance. Retention related balances will be presented as a separate contract asset instead of a component of accounts receivable on the face of the balance sheet. Management will evaluate the nature of warranties provided to the Company’s customers to determine if such warranties represent an assurance-type or service-type warranty, which requires identification and treatment as a separate performance obligation. For purposes of revenue recognition, such warranties are currently included in total estimated project costs. Further, management intends to develop a process for calculating the balance of remaining unsatisfied performance obligations, which is a required disclosure under the new revenue recognition standard that may differ from the historical calculation of backlog, although we intend to continue disclosing backlog in our future SEC filings. We expect to separately present contract assets and liabilities in our consolidated balance sheets. Contract assets will include amounts due under contractual retainage provisions, unbilled receivables and costs and estimated earnings in excess of billings. Contract liabilities will include provisions for losses and billings in excess of costs and estimated earnings. We are currently drafting revised accounting policies and evaluating the enhanced disclosure requirements on our business processes, controls and systems. Using the modified retrospective method, we anticipate adopting this standard for fiscal year 2019 and for interim periods beginning in fiscal year 2020. As a result of the review of our various types of revenue arrangements, we do not anticipate that the adoption will have a material impact on our Condensed Consolidated Financial Statements, particularly as it relates to revenues generated from long-term construction, service maintenance, and time and materials contracts. In February 2016, the FASB issued ASU No. 2016‑02, “Leases (Topic 842),” ASU 2016‑02 provides an approach for classifying leases as either finance leases or operating leases. For either classification, a right-of-use asset and a lease liability will be required to be recognized, unless the term of the lease is one year or less. The guidance is required to be applied using a modified retrospective approach which includes optional practical expedients. In January 2018, the FASB issued ASU No. 2018‑01, “Leases (Topic 842),” that clarified the standard by providing a practical expedient in transition to not evaluate existing or expired land easements under Topic 842 that were not previously accounted for as leases under Topic 840. In July 2018, the FASB issued ASU 2018‑10, “Codification Improvements to Topic 842, Leases,” to correct inconsistencies in the guidance and clarify how to apply certain provisions of the lease standards. In addition, the FASB issued ASU No. 2018‑11, “Leases (Topic 842): Targeted Improvements,” intended to reduce costs and ease implementation of the leases standard for financial statement preparers by providing a new transition method and a practical expedient for separating components of a contract. Under the new transition method, an entity initially applies the new leases standard at the adoption date and recognizes a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. Because the Company’s EGC status is set to expire on December 31, 2019, the Company is expected to comply with this standard beginning in the fourth quarter of 2019. Earlier application is permitted. During the second quarter of 2019, we engaged a service provider to assist us in evaluating the impact of the new pronouncement. As management has not yet commenced its analysis of these standards, it therefore cannot estimate the impact of their adoption on the Condensed Consolidated Financial Statements. In November 2016, the FASB issued ASU 2016‑18, “Statement of Cash Flows: Restricted Cash” to address diversity in practice in the classification and presentation of changes in restricted cash on the statement of cash flows. The guidance is effective for financial statements issued for annual periods beginning after December 15, 2018, and for interim periods beginning after December 15, 2019. Early adoption is permitted, including adoption in an interim period. If an entity early adopts the amendments in an interim period, any adjustments should be reflected as of the beginning of the year that includes that interim period. An entity that elects early adoption must adopt all of the amendments in the same period. The amendments should be applied using a retrospective transition method to each period presented. On January 1, 2019, the Company adopted the provisions of ASU 2016‑18 using the retrospective transition method. As a result, changes in restricted cash are now included in the beginning of period and end of period total cash, cash equivalents and restricted cash amounts. See Note 2 for further details. In January 2017, the FASB issued ASU 2017‑01, “Business Combinations (Topic 805): Clarifying the Definition of a Business” to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The amendments provide a screen to determine when a set of assets and activities is not a business. If the screen is not met, the amendments require further consideration of inputs, substantive processes and outputs to determine whether the transaction is an acquisition of a business. This guidance is effective for financial statements issued for annual periods beginning after December 15, 2018, and for interim periods within annual periods beginning after December 15, 2019. The amendments in this update are to be applied prospectively on or after the effective date. The adoption of this standard is not anticipated to have a material impact on the previously issued Condensed Consolidated Financial Statements. In January 2017, the FASB issued ASU 2017‑04, “Intangibles–Goodwill and Other - Simplifying the Test for Goodwill Impairment” to address the cost and complexity of the goodwill impairment test which resulted in the elimination of Step 2 from the goodwill impairment test. Step 2 measured a goodwill impairment loss by comparing the implied fair value of goodwill by assigning fair value of a reporting unit to all of its assets and liabilities as if that reporting unit had been acquired in a business combination. Rather, the Company would be required to do its annual and interim goodwill impairment tests by comparing the fair value of the reporting unit with its carrying amount and to recognize an impairment charge for the amount by which the carrying amount is greater than the reporting unit’s fair value, not to exceed the total amount of goodwill allocated to that reporting unit. Income tax effects measuring the goodwill impairment loss, if applicable, from any tax deductible goodwill on the carrying amount on the reporting unit should also be considered. The guidance is effective for financial statements issued for the Company’s annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2021. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The amendments in this update are to be applied on a prospective basis. Management adopted this standard in the first quarter of 2019 and will apply the guidance within the standard when performing the Company’s annual or any interim impairment tests. The adoption of this standard did not have a material impact on the Condensed Consolidated Financial Statements. In June 2018, the FASB issued ASU 2018‑07, “Compensation – Stock Compensation (Topic 718): Improvements to Non-employee Share-Based Accounting,” to simplify the accounting for share-based payment transactions to non-employees for goods and services by aligning it with the guidance for share-based payments to employees. Because the Company’s EGC status is set to expire on December 31, 2019, unless other disqualifying provisions apply prior to that date (see Item 2. JOBS Act), the Company is expected to comply with this standard beginning the fourth quarter of 2019. Early adoption is permitted, but no earlier than an entity’s adoption date of ASU 2014‑09, “Revenue from Contracts with Customers—Topic 606.” The adoption of this standard is expected to have no material impact on the Condensed Consolidated Financial Statements. In August 2018, the FASB issued ASU 2018‑13, “Fair Value Measurement (Topic 820): Disclosure Framework – Changes to the Disclosure Requirements for Fair Value Measurement,” to improve the effectiveness of disclosures in the notes to financial statements related to recurring or nonrecurring fair value measurements by removing amounts and reasons for transfers between Level 1 and Level 2 of the fair value hierarchy, the policy for timing of transfers between levels, and the valuation processes for Level 3 fair value measurements. The new standard requires disclosure of the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements. The amendments in this update are effective for all entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. The adoption of this standard only impacts disclosure; therefore, the Company does not expect that it will have an impact on the Condensed Consolidated Financial Statements.

Accounts Receivable and Allowan

Accounts Receivable and Allowance for Doubtful Accounts	6 Months Ended
	Jun. 30, 2019
Accounts Receivable and Allowance for Doubtful Accounts
Accounts Receivable and Allowance for Doubtful Accounts	Note 4 – Accounts Receivable and Allowance for Doubtful Accounts Accounts receivable and the allowance for doubtful accounts are comprised of the following: ( in thousands ) June 30, 2019 December 31, 2018 Accounts receivable $ 111,803 $ 106,063 Retainage 31,236 29,867 Allowance for doubtful accounts (278) (243) Accounts receivable, net $ 142,761 $ 135,687

Contracts in Progress

Contracts in Progress	6 Months Ended
	Jun. 30, 2019
Contracts in Progress
Contracts In Progress	Note 5 – Contracts in Progress ( in thousands ) June 30, 2019 December 31, 2018 Revenue earned on uncompleted contracts $ 765,794 $ 731,923 Less: Billings to date (776,300) (750,068) Net underbilling (overbilling) $ (10,506) (18,145) The above is reflected in the accompanying Condensed Consolidated Balance Sheets as follows: Costs and estimated earnings in excess of billing on uncompleted contracts $ 36,030 $ 32,698 Billings in excess of costs and estimated earnings on uncompleted contracts (46,536) (50,843) Net underbilling (overbilling) $ (10,506) $ (18,145) Accounts payable includes retainage due to subcontractors totaling $11.7 million and $13.0 million as of June 30, 2019 and December 31, 2018, respectively. The Company has asserted claims and unapproved change orders on certain construction projects. These occur typically as a result of scope changes and project delays. Management continually evaluates these items and estimates the recoverable amounts and, if significant, these recoverability estimates are evaluated to determine the net realizable value. If additional amounts are recovered, additional contract revenue would be recognized. For the three months ended June 30, 2019, we recorded revisions in our contract estimates for certain construction and service projects. For individual projects with revisions having a material gross profit impact, this resulted in gross profit write ups totaling $0.3 million on one construction project and $0.3 million on one service project. We also recorded revisions in contract estimates that resulted in project write downs totaling $1.9 million on three construction projects for our Southern California region. For the six months ended June 30, 2019, we recorded revisions in our contract estimates for certain construction and service projects. For individual construction projects with revisions having a material gross profit impact, this resulted in gross profit write ups totaling $3.0 million on six projects, including three projects totaling $1.0 million for our Mid-Atlantic region. One of these project write ups in the amount of $1.4 million resulted from our settlement of a significant Michigan project. We also recorded revisions in contract estimates that resulted in project write downs totaling $3.5 million on seven projects, including four projects totaling $2.2 million in our Southern California region and one project for $0.5 million in our Mid-Atlantic region. Revisions in our contract estimates on one service project resulted in a gross profit write up of $0.3 million on a Mid-Atlantic project during this period and one Southern California project resulted in a gross profit write down of $0.3 million.

Goodwill and Intangibles

Goodwill and Intangibles	6 Months Ended
	Jun. 30, 2019
Goodwill and Intangibles
Goodwill and Intangibles	Note 6 – Goodwill and Intangibles Goodwill and intangible assets consist of the following: Gross carrying Accumulated Net intangible (in thousands) amount amortization assets June 30, 2019 Amortized intangible assets: Backlog – Construction $ 4,830 $ (4,830) $ — Customer Relationships – Service 4,710 (2,397) 2,313 Favorable Leasehold Interests 530 (200) 330 Total amortized intangible assets 10,070 (7,427) 2,643 Unamortized intangible assets: Trade Name 9,960 — 9,960 Total unamortized intangible assets 9,960 — 9,960 Total amortized and unamortized assets, excluding goodwill $ 20,030 $ (7,427) $ 12,603 Goodwill $ 10,488 $ — $ 10,488 Gross carrying Accumulated Net intangible (in thousands) amount amortization assets December 31, 2018 Amortized intangible assets: Backlog – Construction $ 4,830 $ (4,830) $ — Customer Relationships – Service 4,710 (2,081) 2,629 Favorable Leasehold Interests 530 (166) 364 Total amortized intangible assets 10,070 (7,077) 2,993 Unamortized intangible assets: Trade Name 9,960 — 9,960 Total unamortized intangible assets 9,960 — 9,960 Total amortized and unamortized assets, excluding goodwill $ 20,030 $ (7,077) $ 12,953 Goodwill $ 10,488 $ — $ 10,488 The definite-lived intangible assets are amortized over the period the Company expects to receive the related economic benefit, which for customer relationships is based upon estimated future net cash inflows. The Company has previously determined that its trade name has an indefinite useful life. The Limbach trade name has been in existence since the Company’s founding in 1901 and is an established brand within the construction industry. Total amortization expense for these amortizable intangible assets was $0.1 million for the three months ended June 30, 2019 and $0.3 million for the three months ended June 30, 2018. Total amortization expense for these amortizable intangible assets was $0.4 million for the six months ended June 30, 2019 and $0.7 million for the six months ended June 30, 2018. The Company did not recognize any impairment charges for the three or six months ended June 30, 2019 or June 30, 2018.

Debt

Debt	6 Months Ended
	Jun. 30, 2019
Debt
Debt	Note 7 – Debt Long-term debt consists of the following obligations as of: June 30, December 31, (in thousands) 2019 2018 Credit Agreement – revolver (1) $ — $ — Bridge Term Loan – term loan payable in quarterly installments of principal, plus interest through April 2019 (1) — 7,736 Credit Agreement – term loan payable in quarterly installments of principal, plus interest through March 2020 (1) — 14,335 2019 Revolving Credit Facility — — 2019 Refinancing Term Loan – term loan payable in quarterly installments of principal, (commencing in September 2020) plus interest through April 2022 40,000 — Long-term portion of 2019 Refinancing Term Loan embedded derivative 177 — Capital leases – collateralized by vehicles, payable in monthly installments of principal, plus interest ranging from 4.95% to 6.1% through 2023 5,587 5,145 Total debt 45,764 27,216 Less - Current portion of long-term debt (2,173) (3,141) Less - Unamortized discount and debt issuance costs (3,608) (461) Long-term debt $ 39,983 $ 23,614 (1) On April 12, 2019, the Company entered into the Refinancing Agreements (as defined below) and used the net proceeds to repay its existing indebtedness under the Credit Agreement (as defined below). Credit Agreement Effective July 20, 2016, LFS, a subsidiary of the Company, entered into the Credit Agreement (as amended, the “Credit Agreement”). The Credit Agreement consisted of a $25.0 million revolving line of credit (the “Credit Agreement Revolver”) and a $24.0 million term loan (the “Credit Agreement Term Loan”), both with a maturity date of July 20, 2021. The Credit Agreement was collateralized by substantially all of the assets of LFS and its subsidiaries. Principal payments of $750,000 on the term loan were due quarterly through June 30, 2018. Principal payments of $900,000 were due at the end of subsequent quarters through maturity of the loan, with any remaining amounts due at maturity. Outstanding borrowings on both the term loan and the revolving line of credit bore interest at either the Base Rate (as defined in the Credit Agreement) or LIBOR (as defined in the Credit Agreement), plus the applicable additional margin, payable monthly. Mandatory prepayments were required upon the occurrence of certain events, including, among other things and subject to certain exceptions, equity issuances, changes of control of the Company, certain debt issuances, assets sales and excess cash flow. The Company could voluntarily prepay the loans at any time subject to the limitations set forth in the Credit Agreement. The Credit Agreement included restrictions on, among other things and subject to certain exceptions, the Company and its subsidiaries’ ability to incur additional indebtedness, pay dividends or make other distributions, redeem or purchase capital stock, make investments and loans and enter into certain transactions, including selling assets, engaging in mergers or acquisitions and entering into transactions with affiliates. On January 12, 2018, LFS and LHLLC entered into the Second Amendment and Limited Waiver to the Credit Agreement (the “Second Amendment and Limited Waiver”) with the lenders party thereto and Fifth Third Bank, as administrative agent. The Second Amendment and Limited Waiver provided for a new term loan under the Credit Agreement in the aggregate principal amount of $10.0 million (the “Bridge Term Loan”), the proceeds of which were used to repurchase the Company’s remaining 280,000 shares of Class A Preferred Stock for an aggregate purchase price of $9.1 million plus accrued but unpaid dividends of $0.9 million. Loans under the Credit Agreement bore interest, at the Borrower’s option, at either Adjusted LIBOR (“Eurodollar”) or a Base Rate, in each case, plus an applicable margin. With respect to the Bridge Term Loan, from January 12, 2018 to, but excluding, July 12, 2018 (the six-month anniversary of the loan), the applicable margin with respect to any Base Rate loans was 4.00% per annum and with respect to any Eurodollar loan was 5.00% per annum. From July 12, 2018 to, but excluding, the 12-month anniversary thereof, the applicable margin with respect to any Base Rate loan was 4.50% per annum and with respect to any Eurodollar loan was 5.50% per annum. From the 12-month anniversary of January 12, 2018 and all times thereafter, the applicable margin with respect to any Base Rate loan was 5.00% per annum and with respect to a Eurodollar loan was 6.00% per annum. The borrower was required to make principal payments on the Bridge Term Loan in the amount of $250,000 on the last business day of March, June, September and December of each year, commencing on March 31, 2018. The Bridge Term Loan was to mature on April 12, 2019; however, the balance was refinanced under the 2019 Refinancing Agreements (as defined below) prior to maturity. The Bridge Term Loan was guaranteed by the same Guarantors and secured (on a pari passu basis) by the same Collateral as the loans under the Credit Agreement. On March 21, 2018, the Company, LFS and LHLLC entered into the Third Amendment to Credit Agreement (the “Third Amendment”) with the lenders party thereto and Fifth Third Bank, as administrative agent and L/C Issuer. The Third Amendment provided for an increase in the amount that could be drawn against the Credit Agreement Revolver for the issuances of letters of credit from $5.0 million to $8.0 million, modified the definition of EBITDA to include certain one-time costs and non-cash charges and joined the Company as a guarantor under the Credit Agreement and related loan documents. On May 15, 2018, the Company, LFS and LHLLC entered into the Fourth Amendment to Credit Agreement and Limited Waiver (the “Fourth Amendment and Limited Waiver”) with the lenders party thereto and Fifth Third Bank, as administrative agent and L/C Issuer. The Fourth Amendment and Limited Waiver amended the existing covenants of the Credit Agreement to include additional information covenants, such as work in process reports and monthly cash flow schedules. In addition, the Fourth Amendment and Limited Waiver required a fixed charge coverage ratio of not less than 1.15 for the fiscal quarter ended June 30, 2018. On August 13, 2018, the Company, LFS and LHLLC entered into the Fifth Amendment to Credit Agreement and Limited Waiver (the “Fifth Amendment and Limited Waiver”) with the lenders party thereto and Fifth Third Bank, as administrative agent and L/C Issuer. The Fifth Amendment and Limited Waiver amended the existing covenants of the Credit Agreement and required the Company to engage a consultant for the purposes of making recommendations as to methods of the Company’s corporate and Mid-Atlantic’s operations and controls. In addition, the Fifth Amendment and Limited Waiver required a fixed charge coverage ratio of not less than 1.15 for the fiscal quarter ended March 30, 2019 and not less than 1.25 at all times thereafter. During the third quarter of 2018, the Company was not in compliance with the then-existing debt covenants. As a result of these violations, the lenders requested that the Company seek alternative financing. On November 30, 2018, the Company, LFS and LHLLC entered into a Sixth Amendment to Credit Agreement and Limited Waiver (the “Sixth Amendment and Limited Waiver”) with the lenders party thereto and Fifth Third Bank, as administrative agent and L/C Issuer, pursuant to which the administrative agent and certain lenders thereto agreed to a waiver of the Company’s non-compliance with the senior leverage and fixed charge coverage ratio requirements under the Credit Agreement. In addition, the Sixth Amendment and Limited Waiver amended the Credit Agreement to, among other things, (i) reduce the Lenders’ $25.0 million commitment under the Company’s Credit Agreement Revolver to $22.5 million on December 31, 2018 and $20.0 million on January 31, 2019, (ii) accelerate the maturity date for the Credit Agreement revolver and the Credit Agreement Term Loan facility from July 20, 2021 to March 31, 2020, and (iii) require that certain actions be taken in connection with the refinancing of the Company’s obligations under the Credit Agreement by certain scheduled dates. The Credit Agreement, as amended, required the Company to comply with certain financial performance covenants including the following: (1) a minimum EBITDA of $6.5 million for the fourth quarter of 2018, (2) a fixed charge coverage ratio not less than 1.10 for each fiscal quarter ending on or after March 31, 2019 (which was decreased from 1.15 for the fiscal quarters ending on June 30, 2018 through December 31, 2018) and (3) unfinanced capital expenditures not to exceed $1.0 million for each fiscal quarter ending March 31, 2019, June 30, 2019, and September 30, 2019; no unfinanced capital expenditures for the fiscal quarter ending December 31, 2019 and total unfinanced capital expenditures not to exceed $3.0 million for the fiscal year ended December 31, 2019; and no unfinanced capital expenditures where the Company fails to achieve the required fixed charge coverage ratio for such date. The equity interests of the Company’s subsidiaries were pledged as security for the obligations under the Credit Agreement. The Credit Agreement included customary events of default, including, among other items, payment defaults, cross-defaults to other indebtedness, a change of control default and events of default with respect to certain material agreements. Additionally, with respect to the Company, an event of default was deemed to have occurred if the Company’s securities ceased to be registered with the SEC pursuant to Section 12(b) of the Exchange Act. In case of an event of default, the administrative agent was entitled to, among other things, accelerated payment of amounts due under the Credit Agreement, foreclose on the equity of the Company’s subsidiaries, and exercise all rights of a secured creditor on behalf of the lenders. As of December 31, 2018, the Company was in compliance with the financial and other covenants related to the Credit Agreement. At December 31, 2018, the Company had irrevocable letters of credit in the amount of $3.4 million with its lender to secure obligations under its self-insurance program. The additional margin applied to both the Credit Agreement revolver and Credit Agreement term loan is determined based on levels achieved under the Company’s senior leverage ratio covenant, which reflects the ratio of indebtedness divided by EBITDA for the most recently ended four quarters. The following is a summary of the additional margin and commitment fees payable on the prior revolving credit commitment: Additional Margin for Additional Margin for Level Senior Leverage Ratio Base Rate loans Libor Rate loans Commitment Fee I Greater than or equal to 2.50 to 1.00 3.00 % 4.00 % 0.50 % II Less than 2.50 to 1.00, but greater than or equal to 2.00 to 1.00 2.75 % 3.75 % 0.50 % III Less than 2.00 to 1.00, but greater than or equal to 1.50 to 1.00 2.50 % 3.50 % 0.50 % IV Less than 1.50 to 1.00 2.25 % 3.25 % 0.50 % The Company refinanced its Credit Agreement Revolver on April 12, 2019 under the 2019 Refinancing Agreement, described below and therefore had no amounts outstanding under its Credit Agreement at June 30, 2019. 2019 Refinancing Agreement On April 12, 2019 (the “Refinancing Closing Date”), LFS entered into a financing agreement (the “2019 Refinancing Agreement”) with the lenders thereto and Cortland Capital Market Services LLC, as collateral agent and administrative agent and CB Agent Services LLC, as origination agent (“CB”). The 2019 Refinancing Agreement consists of (i) a $40.0 million term loan (the “2019 Refinancing Term Loan”) and (ii) a new $25.0 million multi-draw delayed draw term loan (the “2019 Delayed Draw Term Loan” and, collectively with the 2019 Refinancing Term Loan, the “2019 Term Loans”). Proceeds from the 2019 Refinancing Term Loan were used to repay the then existing Credit Agreement, to pay related fees and expenses thereof and to fund working capital of the Borrowers (defined below). Proceeds of the 2019 Delayed Draw Term Loan will be used to fund permitted acquisitions under the 2019 Refinancing Agreement and related fees and expenses in connection therewith. LFS, a wholly-owned subsidiary of the Company, and each of its subsidiaries are borrowers (the “Borrowers”) under the 2019 Refinancing Agreement. In addition, the 2019 Refinancing Agreement is guaranteed by the Company and LHLLC (each, a “Guarantor”, and together with the Borrowers, the “Loan Parties”). The 2019 Refinancing Agreement is secured by a first-priority lien on the real property of the Loan Parties and a second-priority lien on substantially all other assets of the Loan Parties, behind the 2019 ABL Credit Agreement (as defined below). The respective lien priorities of the 2019 Refinancing Agreement and the 2019 ABL Credit Agreement are governed by an intercreditor agreement. 2019 Refinancing Agreement - Interest Rates and Fees The interest rate on borrowings under the 2019 Refinancing Agreement is, at the Borrowers’ option, either LIBOR (with a 2.00% floor) plus 8.00% or a base rate (with a 3.00% minimum) plus 7.00%. At June 30, 2019, the interest rate in effect on the 2019 Refinancing Term Loan was 10.54%. 2019 Refinancing Agreement - Other Terms and Conditions The 2019 Refinancing Agreement matures on April 12, 2022, subject to adjustment as described therein. Required amortization is $1.0 million per quarter commencing with the fiscal quarter ending September 30, 2020. There is an unused line fee of 2.0% per annum on the undrawn portion of the 2019 Delayed Draw Term Loan, and there is a make-whole premium on prepayments made prior to the 19‑month anniversary of the Refinancing Closing Date. This make-whole provision guarantees that the Company will pay no less than 18 months’ applicable interest to the lenders under the 2019 Refinancing Agreement. The 2019 Refinancing Agreement contains representations and warranties, and covenants which are customary for debt facilities of this type. Unless the Required Lenders (as defined in the 2019 Refinancing Agreement) otherwise consent in writing, the covenants limit the ability of the Company and its restricted subsidiaries to, among other things, (i) incur additional indebtedness or issue preferred stock, (ii) pay dividends or make distributions to the Company’s stockholders, (iii) purchase or redeem the Company’s equity interests, (iv) make investments, (v) create liens on their assets, (vi) enter into transactions with the Company’s affiliates, (vii) sell assets and (viii) merge or consolidate with, or dispose of substantially all of the Company’s assets to, other companies. In addition, the 2019 Refinancing Agreement includes customary events of default and other provisions that could require all amounts due thereunder to become immediately due and payable, either automatically or at the option of the lenders, if the Company fails to comply with the terms of the 2019 Refinancing Agreement or if other customary events occur. Furthermore, the 2019 Refinancing Agreement also contains two financial maintenance covenants for the 2019 Refinancing Term Loan, including a requirement to have sufficient collateral coverage of the aggregate outstanding principal amount of the 2019 Refinancing Term Loans and for the total leverage ratio of the Company and its Subsidiaries not to exceed an amount beginning at 4.25 to 1.00 through June 30, 2019, and stepping down to 2.00 to 1.00 effective July 1, 2021. From July 1, 2019 through September 30, 2019, the Total Leverage Ratio may not exceed 4.00 to 1.00. The 2019 Refinancing Agreement contains a post-closing covenant requiring the remediation of the Company’s material weakness, as described in Item 9A of its 2018 Annual Report on Form 10-K, no later than December 31, 2020 and to provide updates as to the progress of such remediation, provided that, if such remediation has not been completed on or prior to December 31, 2019, (x) the Company shall be required to pay the post-closing fee pursuant to the terms of the Origination Agent Fee Letter (as defined in the 2019 Refinancing Agreement) and (y) the applicable margin shall be increased by 1.00 % per annum for the period from January 1, 2020 until the date at which the material weakness is no longer disclosed or required to be disclosed in the Company’s SEC filings or audited financial statements of the Company or related auditor’s reports. 2019 Refinancing Agreement – CB Warrants In connection with the 2019 Refinancing Agreement, on the Refinancing Closing Date, the Company issued to CB and the other lenders under the 2019 Refinancing Agreement warrants (the “CB Warrants”) to purchase up to a maximum of 263,314 shares of the Company’s common stock at an exercise price of $7.63 per share subject to certain adjustments, including for stock dividends, stock splits or reclassifications. The actual number of shares of common stock into which the CB Warrants will be exercisable at any given time will be equal to: (i) the product of (x) the number of shares equal to 2% of the Company’s issued and outstanding shares of common stock on the Refinancing Closing Date on a fully diluted basis and (y) the percentage of the total 2019 Delayed Draw Term Loan made as of the exercise date, minus (ii) the number of shares previously issued under the CB Warrants. As of the Refinancing Closing Date and June 30, 2019, no amounts had been drawn on the 2019 Delayed Draw Term Loan, so no portion of the CB Warrants were exercisable. The CB Warrants may be exercised for cash or on a “cashless basis,” subject to certain adjustments, at any time after the Refinancing Closing Date until the expiration of such warrant at 5:00 p.m., New York time, on the earlier of (i) the five (5) year anniversary of the Refinancing Closing Date, or (ii) the liquidation of the Company. Accounting for the 2019 Term Loans and CB Warrants The CB Warrants represent a freestanding financial instrument that is classified as a liability because the CB Warrants meet the definition of a derivative instrument that does not meet the equity scope exception (i.e., the CB Warrants are not indexed to the entity's own equity). In addition, the material weakness penalty described above was evaluated as an embedded derivative liability and bifurcated from the 2019 Term Loans as it represents a non-credit related embedded feature that provides for net settlement. Both the CB Warrants liability and the embedded derivative liability are required to be initially and subsequently measured at fair value. The initial fair values of the CB Warrants liability and the embedded derivative liability approximated $0.9 million and $0.4 million, respectively, on the Refinancing Closing Date. The CB Warrants liability is included in other long-term liabilities. The current portion of the embedded derivative liability of $0.2 million is included in accrued expenses and other current liabilities and the long-term portion of $0.2 million is included in long-term debt. The Company estimated these fair values by using the Black-Scholes -Merton option pricing model and a probability-weighted discounted cash flow approach, respectively. The proceeds for the 2019 Term Loan were first allocated to the CB Warrants liability and embedded derivative liability based on their respective fair values with a corresponding amount of $1.3 million recorded as a debt discount to the 2019 Term Loans. In addition, the Company incurred approximately $2.5 million of debt issuance costs for the 2019 Term Loans that have also been recorded as a debt discount. The combined debt discount from the CB Warrants liability, embedded derivative liability and the debt issuance costs is being amortized into interest expense over the term of the 2019 Term Loans using the effective interest method. The Company recorded interest expense for the amortization of the CB Warrants liability and embedded derivative debt discounts of $0.1 million for the three months ended June 30, 2019 and recorded an additional $0.2 million of interest expense for the amortization of the debt issuance costs for the three months ended June 30, 2019. The Company remeasured the fair value of the CB Warrants liability and embedded derivative liability as of June 30, 2019 and recorded any adjustments as other income (expense). The Company estimated these fair values by using the Black-Scholes -Merton option pricing model and a probability-weighted discounted cash flow approach, respectively. For the three months ended June 30, 2019, the Company recorded other expense of approximately $0.1 million and $0 to reflect the change in fair values of the CB Warrants liability and the embedded derivative liability, respectively. 2019 ABL Credit Agreement On the Refinancing Closing Date, LFS also entered into a financing agreement with the lenders thereto and Citizens Bank, N.A., as collateral agent, administrative agent and origination agent (the “2019 ABL Credit Agreement” and, together with the 2019 Refinancing Agreement, the “Refinancing Agreements”). The 2019 ABL Credit Agreement consists of a $15.0 million revolving credit facility (the “2019 Revolving Credit Facility”). Proceeds of the 2019 Revolving Credit Facility may be used for general corporate purposes. On the Refinancing Closing Date, the Company had nothing drawn on the ABL Credit Agreement and $14.0 million of available borrowing capacity thereunder (net of a $1.0 million reserve imposed by the lender). The Borrowers and Guarantors under the 2019 ABL Credit Agreement are the same as under the 2019 Refinancing Agreement. The 2019 ABL Credit Agreement is secured by a second-priority lien on the real property of the Loan Parties (behind the 2019 Refinancing Agreement) and a first-priority lien on substantially all other assets of the Loan Parties. 2019 ABL Credit Agreement - Interest Rates and Fees The interest rate on borrowings under the 2019 ABL Credit Agreement is, at the Borrowers’ option, either LIBOR (with a 2.0% floor) plus an applicable margin ranging from 3.00% to 3.50% or a base rate (with a 3.0% minimum) plus an applicable margin ranging from 2.00% to 2.50%. 2019 ABL Credit Agreement - Other Terms and Conditions The 2019 ABL Credit Agreement matures on April 12, 2022. There is an unused line fee ranging from 0.250% to 0.375% per annum on undrawn amounts. The 2019 ABL Credit Agreement contains representations and warranties, and covenants which are customary for debt facilities of this type. Unless the Required Lenders otherwise consent in writing, the covenants limit the ability of the Company and its restricted subsidiaries to, among other things, to (i) incur additional indebtedness or issue preferred stock, (ii) pay dividends or make distributions to the Company’s stockholders, (iii) purchase or redeem the Company’s equity interests, (iv) make investments, (v) create liens on their assets, (vi) enter into transactions with the Company’s affiliates, (vii) sell assets and (viii) merge or consolidate with, or dispose of substantially all of the Company’s assets to, other companies. The 2019 ABL Credit Agreement includes customary events of default and other provisions that could require all amounts due thereunder to become immediately due and payable, either automatically or at the option of the lenders, if the Company fails to comply with the terms of the 2019 ABL Credit Agreement or if other customary events occur. The 2019 ABL Credit Agreement also contains a financial maintenance covenant for the 2019 Revolving Credit Facility, which is a requirement for the total leverage ratio of the Company and its Subsidiaries not to exceed an amount beginning at 4.00 to 1.00 through September 30, 2019, and stepping down to 1.75 to 1.00 effective July 1, 2021. Accounting for the 2019 ABL Credit Agreement As of June 30, 2019, the Company had nothing drawn on the 2019 ABL Credit Agreement. In addition, the Company incurred approximately $0.9 million of debt issuance costs for the 2019 ABL Credit Agreement that have been recorded as a non-current deferred asset. The deferred asset is being amortized into interest expense over the term of the 2019 Term ABL Credit Agreement using the effective interest method. The Company recorded interest expense of $0.1 million for the amortization the debt issuance costs for the three months ended June 30, 2019.

Equity

Equity	6 Months Ended
	Jun. 30, 2019
Equity
Equity	Note 8 – Equity The Company’s second amended and restated certificate of incorporation currently authorizes the issuance of 100,000,000 shares of common stock, par value $0.0001, and 1,000,000 shares of preferred stock, par value $0.0001. At June 30, 2019 and December 31, 2018, the Company had outstanding warrants exercisable for 4,576,799 shares of common stock, consisting of: (i) 4,600,000 warrants issued as part of units in its initial public offering, each of which is exercisable for one-half of one share of common stock at an exercise price of $11.50 per whole share (“Public Warrants”); (ii) 198,000 warrants, each exercisable for one-half of one share of common stock at an exercise price of $5.75 per half share ($11.50 per whole share) (“Sponsor Warrants”); (iii) 600,000 warrants, each exercisable for one share of common stock at an exercise price of $15.00 per share (“$15 Exercise Price Warrants”); (iv) 631,119 warrants, each exercisable for one share of common stock at an exercise price of $12.50 per share (“Merger Warrants”); and (v) 946,680 warrants, each exercisable for one share of common stock at an exercise price of $11.50 per share (“Additional Merger Warrants”). The Public Warrants, Sponsor Warrants and $15 Exercise Price Warrants were issued under a warrant agreement dated July 15, 2014, between Continental Stock Transfer & Trust Company, as warrant agent, and the Company. The Merger Warrants and Additional Merger Warrants were issued to the sellers of LHLLC. On January 8, 2018, the Company issued 10,627 shares of common stock in connection with the cashless exercise of 49,604 Additional Merger Warrants and 33,069 Merger Warrants. On July 21, 2014, a total of 300,000 Unit Purchase Options (“UPOs”) were issued by 1347 Capital to a representative of the underwriter and its designees. In December 2016, the Company issued 121,173 shares of common stock in connection with the cashless exercise of 282,900 of these UPOs. At June 30, 2019 and December 31, 2018, a total of 17,100 UPOs were outstanding and were exercisable, either for cash or on a cashless basis, through July 21, 2019. Each UPO consisted of one share of common stock, one right to purchase one-tenth of one share of common stock and one warrant to purchase one-half of one share of common stock at an exercise price of $11.50 per full share. In August 2017, the Compensation Committee of the Board of Directors of the Company commenced the granting of restricted stock units (“RSUs”) under the Limbach Holdings, Inc. Omnibus Incentive Plan to certain executive officers, non-executive employees and non-employee directors of the Company in the forms of an inaugural RSU award to executives (the “Inaugural RSU Award”), an annual long-term incentive RSU award (the “LTI RSU Award”), and an RSU award to non-employee directors (“Director RSU Award”). During the second quarter of 2019, the Board of Directors approved an additional 350,000 shares of the Company’s common stock as authorized and reserved for issuance under this plan, making a total of 1,150,000 shares available under this plan. The Company granted additional RSU awards during the first half of 2019. See Note 17 – Management Incentive Plans.

Cumulative Redeemable Convertib

Cumulative Redeemable Convertible Preferred Stock	6 Months Ended
	Jun. 30, 2019
Cumulative Redeemable Convertible Preferred Stock
Cumulative Redeemable Convertible Preferred Stock	Note 9 – Cumulative Redeemable Convertible Preferred Stock In connection with the Business Combination, the Company issued 400,000 shares of Class A preferred stock (the “Preferred Stock”) on July 20, 2016. Each share of Preferred Stock was convertible (at the holder’s election) into two shares of the Company’s common stock (as may be adjusted for any stock splits, reverse stock splits or similar transactions), representing a conversion price of $12.50 per share; provided, that such conversion was in compliance with Nasdaq’s listing requirements. The Preferred Stock ranked senior to all classes and series of outstanding capital stock. The Company agreed to not issue any other shares of capital stock that ranked senior or pari passu to the Preferred Stock while the Preferred Stock was outstanding, unless at least 30% of the proceeds from such issuance were used to redeem Preferred Stock. The holders of the Preferred Stock were, in priority to any other class or series of capital stock, entitled to receive, as and when declared by the board of directors fixed, cumulative, preferential dividends at a rate of: (i) 8% per annum in years one through three from issuance; (ii) 10% per annum in years four through five from issuance; and (iii) 12% per annum thereafter, payable in equal quarterly installments. Dividends on outstanding Preferred Stock accrued day to day from the date of issuance of the Preferred Stock. No dividends in excess of the accrued and unpaid preferred yield in respect of the Preferred Stock were permitted. On July 14, 2017, the Company entered into the Preferred Stock Repurchase Agreement with 1347 Investors pursuant to which (a) the Company repurchased from 1347 Investors a total of 120,000 shares of the Preferred Stock for an aggregate sum of $4.1 million in cash, (b) for a period of six months after such repurchase, the Company had the right to repurchase from 1347 Investors, in one or more transactions, all or a portion of the remaining 280,000 shares of Preferred Stock owned by 1347 Investors for a purchase price equal to 130% of the liquidation value per share plus 130% of any and all accrued but unpaid dividends thereon as of the date of closing of the purchase of such shares and (c) 1347 Investors would not, with respect to the 509,500 shares of common stock held in escrow pursuant to its lock-up arrangement that expired on July 20, 2017, sell or otherwise transfer such shares of common stock during the period from such expiration through October 20, 2017. This repurchase was funded through permitted borrowings under the Company’s Credit Agreement revolving credit facility. The Company retired the repurchased shares. As discussed in Note 7 – Debt, on January 12, 2018, the Company exercised its repurchase right with respect to the remaining 280,000 shares of Preferred Stock using the proceeds from the Bridge Term Loan for an aggregate purchase price of $10.0 million, including a $2.2 million premium and accrued but unpaid dividends of $0.9 million, pursuant to the Preferred Stock Repurchase Agreement. The Company also retired these repurchased shares.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2019
Fair Value Measurements
Fair Value Measurements	Note 10 – Fair Value Measurements The Company measures the fair value of financial assets and liabilities in accordance with ASC Topic 820 – Fair Value Measurements and Disclosures, which defines fair value, establishes a framework for measuring fair value and expands disclosures about fair value measurements. ASC Topic 820 establishes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value and requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to measurements involving significant unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are as follows: · Level 1 — inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that are accessible at the measurement date; · Level 2 — inputs other than quoted prices included in Level 1 that are observable for the asset or liability either directly or indirectly such as quoted prices in active markets for similar assets and liabilities, quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of assets or liabilities; and · Level 3 — unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions. The Company believes that the carrying amounts of its financial instruments, including cash and cash equivalents, trade accounts receivable and accounts payable consist primarily of instruments without extended maturities, which approximate fair value primarily due to their short-term maturities and low risk of counterparty default. We also believe that the face value of the 2019 Refinancing Term Loan approximates its fair value due to the variable rate on such debt. As of June 30, 2019, the Company determined the fair value of its 2019 Refinancing Term Loan at $40.0 million. The fair value was determined using discounted estimated future cash flows using level 3 inputs. To determine the fair value of the warrants issued in connection with the Business Combination, the Company utilized the Black-Scholes model. The fair value of the Company’s warrant liabilities (refer to Note 7) recorded in the Company’s financial statements is determined using the Black-Scholes-Merton option pricing model and the quoted price of the Company’s common stock in an active market, volatility and expected life, is a Level 3 measurement. Volatility is based on the actual market activity of the Company’s stock. The expected life is based on the remaining contractual term of the warrants and the risk-free interest rate is based on the implied yield available on U.S. Treasury Securities with a maturity equivalent to the warrants’ expected life. The table below sets forth the assumptions used within the Black-Scholes-Merton option pricing model to value the Company’s warrant liabilities: Stock price $ 8.13 Exercise price $ 7.63 Time until expiration (years) 4.8 Expected volatility 56.2 % Risk-free interest rate 1.8 % Expected dividend yield 0.0 % The fair value of the Company’s embedded derivative liability recorded in the Company’s financial statements is determined using a probability-weighted discounted cash flow approach utilizing inputs including the imposed 2019 Refinancing Agreement Lender material weakness fee of 1.00% of the Total Term Loan Commitment as in effect on the Effective Date as well as the applicable margin increase of 1.00 % per annum as outlined in Note 7. Level 3 rollforward table: (in thousands) Embedded CB Warrants Derivative Liability Liability Fair value, December 31, 2018 $ — $ — Issuances — — Transfers — — Change in fair value — — Fair value,March 31, 2019 — — Issuances 969 388 Transfers — — Change in fair value 103 — Fair value, June 30, 2019 $ 1,072 $ 388

Earnings per Share

Earnings per Share	6 Months Ended
	Jun. 30, 2019
Earnings per Share
Earnings per Share	Note 11 – Earnings per Share Diluted EPS assumes the dilutive effect of outstanding common stock warrants, UPOs and RSUs, all using the treasury stock method, and the dilutive effect of the Class A Preferred Stock, using the “if-converted” method. Three months ended Six months ended June 30, June 30, (in thousands, except per share amounts) 2019 2018 2019 2018 EPS numerator: Net income (loss) $ (1,504) $ 709 $ 642 $ (1,715) Less: Premium paid on partial preferred redemption — — — 2,219 Less: Undistributed preferred stock dividends — — — (113) Net income (loss) attributable to Limbach Holdings, Inc. common stockholders $ (1,504) $ 709 $ 642 $ (3,821) EPS denominator: Weighted average shares outstanding – basic 7,643 7,543 7,643 7,542 Impact of dilutive securities — 265 74 — Weighted average shares outstanding – diluted 7,643 7,808 7,717 7,542 Basic EPS attributable to common stockholders: Net income (loss) attributable to Limbach Holdings, Inc. common stockholders $ (0.20) $ 0.09 $ 0.08 $ (0.51) Diluted EPS attributable to common stockholders: Net income (loss) attributable to Limbach Holdings, Inc. common stockholders $ (0.20) $ 0.09 $ 0.08 $ (0.51) The following table summarizes the securities that were antidilutive (including warrants, UPOs, RSUs and Preferred Stock after giving effect to their respective conversion to shares of common stock for those units in-the-money, or share equivalents for those units out-of-the-money) and therefore, were not included in the computations of diluted income (loss) per common share: Three months ended Six months ended June 30, June 30, 2019 2018 2019 2018 In-the-money warrants (See Note 8) — — — 277,640 Out-of-the-money warrants (See Note 8) 4,576,799 1,231,119 4,576,799 600,000 Preferred Stock (See Note 9) — — — 34,033 Restricted stock units (RSUs) (See Note 17) (1) 138,782 — 2,867 76,972 In-the-money UPOs (See Note 8) — — — — Out-of-the-money UPOs (See Note 8) 27,360 — 27,360 4,502 Total 4,742,941 1,231,119 4,607,026 993,147 (1) For the three and six months ended June 30, 2019 and 2018, all PRSUs and MRSUs (both as defined below) were not included in the computation of diluted loss per share because the performance and market conditions were not satisfied during the periods and would not be satisfied if the reporting date was at the end of the contingency periods.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2019
Income Taxes
Income Taxes	Note 12 – Income Taxes The Company is taxed as a C corporation. For interim periods, the provision for income taxes (including federal, state, local and foreign taxes) is calculated based on the estimated annual effective tax rate, adjusted for certain discrete items for the full fiscal year. Cumulative adjustments to the Company’s estimate are recorded in the interim period in which a change in the estimated annual effective rate is determined. Each quarter we update our estimate of the annual effective tax rate, and if our estimated tax rate changes, we make a cumulative adjustment. The effective tax benefit rate for the three and six months ended June 30, 2019 was 26.9% and 31.3%, respectively, as compared to an effective tax rate of 29.2% and 30.4% for the three and six months ended June 30, 2018. The Company’s effective tax rates differ from the federal statutory rate of 21% primarily due to state taxes, nondeductible expenses and tax credits. No valuation allowance was required as of June 30, 2019 or December 31, 2018. The Company performed an analysis of its tax positions and determined that no material uncertain tax positions exist. Accordingly, there was no liability for uncertain tax positions as of June 30, 2019 or December 31, 2018. Based on the provisions of ASC Topic 740 - Income Taxes, the Company had no material unrecognized tax benefits as of June 30, 2019 or December 31, 2018.

Operating Segments

Operating Segments	6 Months Ended
	Jun. 30, 2019
Operating Segments
Operating Segments	Note 13 – Operating Segments The Company determined its operating segments on the same basis that it assesses performance and makes operating decisions. The Company manages and measures the performance of its business in two distinct operating segments: Construction and Service. These segments are reflective of how the Company’s Chief Operating Decision Maker (“CODM”) reviews operating results for the purposes of allocating resources and assessing performance. The Company’s CODM is comprised of its Chief Executive Officer, Chief Financial Officer and Chief Operating Officers. The accounting policies of the segments are the same as those described in the summary of significant accounting policies. The CODM evaluates performance based on income from operations of the respective segments after the allocation of Corporate office operating expenses. In accordance with ASC Topic 280 – Segment Reporting, the Company has elected to aggregate all of the construction branches into one Construction reportable segment and all of the service branches into one Service reportable segment. All transactions between segments are eliminated in consolidation. Our Corporate departments provide general and administrative support services to our two operating segments. The CODM allocates costs between segments for selling, general and administrative expenses and depreciation expense. All of the Company’s identifiable assets are located in the United States, which is where the Company is domiciled. The Company does not have sales outside the United States. The Company does not identify capital expenditures and total assets by segment in its internal financial reports due in part to the shared use of a centralized fleet of vehicles and specialized equipment. Interest expense is not allocated to segments because of the corporate management of debt service including interest. Condensed consolidated segment information for the periods presented is as follows: Three months ended June 30, (in thousands) 2019 2018 Statement of Operations Data: Revenue: Construction $ 104,925 $ 113,735 Service 27,828 25,796 Total revenue 132,753 139,531 Gross profit: Construction 10,422 9,501 Service 6,979 6,297 Total gross profit 17,401 15,798 Selling, general and administrative expenses: Construction 8,377 6,696 Service 4,460 3,345 Corporate 4,242 3,644 Total selling, general and administrative expenses 17,079 13,685 Amortization of intangibles 175 336 Operating income (loss) $ 147 $ 1,777 Operating income (loss) for reportable segments $ 147 $ 1,777 Less unallocated amounts: Interest expense, net (1,597) (799) Gain on disposition of property and equipment 9 24 Loss on debt extinguishment (513) — Loss on change in fair value of warrant liability (103) — Total unallocated amounts (2,204) (775) Income (loss) before income taxes $ (2,057) $ 1,002 Other Data: Depreciation and amortization: Construction $ 810 $ 704 Service 223 192 Corporate 427 531 Total other data $ 1,460 $ 1,427 Six months ended June 30, (in thousands) 2019 2018 Statement of Operations Data: Revenue: Construction $ 209,599 $ 210,545 Service 57,105 49,535 Total revenue 266,704 260,080 Gross profit: Construction 23,735 18,772 Service 13,699 10,313 Total gross profit 37,434 29,085 Selling, general and administrative expenses: Construction 15,841 14,455 Service 8,771 7,471 Corporate 8,512 7,425 Total selling, general and administrative expenses 33,124 29,351 Amortization of intangibles 350 671 Operating income (loss) $ 3,960 $ (937) Operating income (loss) for reportable segments $ 3,960 $ (937) Less unallocated amounts: Interest expense, net (2,430) (1,568) Gain on disposition of property and equipment 21 40 Loss on debt extinguishment (513) — Loss on change in fair value of warrant liability (103) — Total unallocated amounts (3,025) (1,528) Income (loss) before income taxes $ 935 $ (2,465) Other Data: Depreciation and amortization: Construction $ 1,590 $ 1,370 Service 429 372 Corporate 854 1,056 Total other data $ 2,873 $ 2,798

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2019
Commitments and Contingencies.
Commitments and Contingencies	Note 14 – Commitments and Contingencies Leases. Operating leases consist primarily of leases for real property and equipment. The leases frequently include renewal options, escalation clauses, and require the Company to pay certain occupancy expenses. Lease expense was approximately $1.3 million and $2.7 million for the three and six months ended June 30, 2019, respectively, compared to $1.1 million and $2.2 million for the three and six months ended June 30, 2018. Capital leases consist primarily of leases for vehicles (see Note 7 – Debt). The leases require monthly payments of principal and interest. All leases transfer title at lease end for a nominal cash buyout. Legal. The Company is continually engaged in administrative proceedings, arbitrations, and litigation with owners, general contractors, suppliers, and other unrelated parties, all arising in the ordinary courses of business. In the opinion of the Company’s management, the results of these actions will not have a material adverse effect on the financial position, results of operations, or cash flows of the Company. LFS and Harper, wholly owned subsidiaries of the Company, were parties to a lawsuit involving a Harper employee who was alleged to be in the course and scope of his employment at the time the personal car he was operating collided with another car causing injuries to three persons and one fatality. During the course of the litigation, the plaintiffs made settlement demands within LFS and Harper’s insurance coverage limits. In October 2018, the plaintiffs agreed to settle and dismiss their lawsuit in exchange for an aggregate payment of $30.0 million from LFS and Harper, which amounts were entirely paid by the Company’s insurance carriers during February 2019. The $30.0 million amounts due from the Company’s insurance carriers and due to the plaintiffs were included in the captions labeled Other current assets and Accrued expenses and other current liabilities in the Condensed Consolidated Balance Sheet as of December 31, 2018. The Company had no monetary exposure, including for punitive damages. This matter was dismissed on April 28, 2019. Surety. The terms of our construction contracts frequently require that we obtain from surety companies, and provide to our customers, payment and performance bonds (“Surety Bonds”) as a condition to the award of such contracts. The Surety Bonds secure our payment and performance obligations under such contracts, and we have agreed to indemnify the surety companies for amounts, if any, paid by them in respect of Surety Bonds issued on our behalf. In addition, at the request of labor unions representing certain of our employees, Surety Bonds are sometimes provided to secure obligations for wages and benefits payable to or for such employees. Public sector contracts require Surety Bonds more frequently than private sector contracts, and accordingly, our bonding requirements typically increase as the amount of public sector work increases. As of June 30, 2019 and December 31, 2018, the Company had approximately $98.3 million and $134.2 million, respectively, in surety bonds outstanding. The Surety Bonds are issued by surety companies in return for premiums, which vary depending on the size and type of bond. Collective Bargaining Agreements. Many of the Company’s craft labor employees are covered by collective bargaining agreements. The agreements require the Company to pay specified wages, provide certain benefits and contribute certain amounts to multi-employer pension plans. If the Company withdraws from any of the multi-employer pension plans or if the plans were to otherwise become underfunded, the Company could incur additional liabilities related to these plans. Although the Company has been informed that some of the multi-employer pension plans to which it contributes have been classified as “critical” status, the Company is not currently aware of any significant liabilities related to this issue.

Self-Insurance

Self-Insurance	6 Months Ended
	Jun. 30, 2019
Self-Insurance
Self-Insurance	Note 15 – Self-Insurance The Company purchases workers’ compensation and general liability insurance under policies with per-incident deductibles of $250 thousand and a $4.2 million maximum aggregate deductible loss limit per year. The components of the self-insurance liability as of June 30, 2019 and December 31, 2018 are as follows: As of As of June 30, December 31, (in thousands) 2019 2018 Current liability — workers’ compensation and general liability $ 487 $ 352 Current liability — medical and dental 424 607 Non-current liability 657 820 Total liability shown in Accrued expenses and other liabilities $ 1,568 $ 1,779 Restricted cash $ 113 $ 113 The restricted cash balance represents an imprest cash balance set aside for the funding of workers’ compensation and general liability insurance claims. This amount is replenished either when depleted or at the beginning of each month.

Backlog

Backlog	6 Months Ended
	Jun. 30, 2019
Backlog
Backlog	Note 16 – Backlog At June 30, 2019 and December 31, 2018, the Company’s contractual Construction backlog, which represents the amount of revenue the Company expects to realize from work to be performed on uncompleted construction contracts in progress, was $536.8 million and $505.5 million, respectively. In addition, Service backlog as of June 30, 2019 and December 31, 2018 was $49.4 million and $54.2 million, respectively.

Management Incentive Plans

Management Incentive Plans	6 Months Ended
	Jun. 30, 2019
Management Incentive Plans
Management Incentive Plans	Note 17 – Management Incentive Plans Upon approval of the Business Combination, the Company adopted the Limbach Holdings, Inc. Omnibus Incentive Plan (the “2016 Plan”). Certain employees, directors and consultants will be eligible to be granted awards under the 2016 Plan, other than incentive stock options, which may be granted only to employees. As of June 30, 2019, the Company had reserved 1,150,000 shares of its common stock for issuance under the 2016 Plan. The number of shares issued or reserved pursuant to the 2016 Plan will be adjusted by the plan administrator, as they may deem appropriate and equitable as a result of stock splits, stock dividends, and similar changes in the Company’s common stock. In connection with the grant of an award, the plan administrator may provide for the treatment of such award in the event of a change in control. All awards are made in the form of shares only. Service-Based Awards In 2019, the Company granted 220,636 service-based RSUs to its executives, certain employees, and non-employee directors under the 2016 Plan. The following table summarizes our service-based RSU activity for the six months ended June 30, 2019: Weighted-Average Grant Date Awards Fair Value Unvested at December 31, 2018 173,087 $ 13.30 Granted 220,636 6.61 Vested (50,222) 13.31 Forfeited (5,418) 9.17 Unvested at June 30, 2019 338,083 $ 9.00 Performance-Based Awards The Company did not grant any performance-based RSUs (“PRSUs”) to its executives and certain employees under the 2016 Plan during the first six months of 2019. The Company will recognize stock-based compensation expense for these awards over the vesting period based on the projected probability of achievement of certain performance conditions as of the end of each reporting period during the performance period and may periodically adjust the recognition of such expense, as necessary, in response to any changes in the Company’s forecasts with respect to the performance conditions. As of June 30, 2019, the Company had not recognized any stock-based compensation expense related to its PRSUs granted to date. The following table summarizes our PRSU activity for the six months ended June 30, 2019: Weighted-Average Grant Date Awards Fair Value Unvested at December 31, 2018 124,057 $ 13.34 Granted — — Vested — — Forfeited (2,750) 13.39 Unvested at June 30, 2019 121,307 $ 13.34 Market-Based Awards The following table summarizes our market-based RSU (“MRSUs”) activity for the six months ended June 30, 2019: Weighted-Average Grant Date Awards Fair Value Unvested at December 31, 2018 140,500 $ 6.58 Granted — — Vested — — Forfeited (3,000) 6.58 Unvested at June 30, 2019 137,500 $ 6.58 Total recognized stock-based compensation expense amounted to $0.5 million and $0.9 million for the three and six months ended June 30, 2019, respectively. The aggregate fair value as of the vest date of RSUs that vested during the six months ended June 30, 2019 and 2018 was $0.2 million and $0.3 million, respectively. Total unrecognized stock-based compensation expense related to unvested RSUs which are probable of vesting was $1.6 million at June 30, 2019. These costs are expected to be recognized over a weighted average period of 1.19 years.

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2019
Significant Accounting Policies
Basis of Presentation	Basis of Presentation Condensed Financial Statements The accompanying unaudited Condensed Consolidated Financial Statements have been prepared in accordance with instructions to the Quarterly Report on Form 10‑Q and Rule 8‑03 of Regulation S-X for smaller reporting companies. Consequently, certain information and note disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) have been condensed or omitted pursuant to those rules and regulations, although the Company believes that the disclosures made are adequate to make the information not misleading. Readers of this report should refer to the consolidated financial statements and the notes thereto included in our latest Annual Report on Form 10‑K filed with the Securities and Exchange Commission (the “SEC”) on April 15, 2019.
Unaudited Interim Financial Information	Unaudited Interim Financial Information The accompanying interim Condensed Consolidated Balance Sheets, Condensed Consolidated Statements of Operations, Condensed Consolidated Statements of Stockholders’ Equity and Condensed Consolidated Statements of Cash Flows for the periods presented are unaudited. Also, within the notes to the Condensed Consolidated Financial Statements, we have included unaudited information for these interim periods. These unaudited interim Condensed Consolidated Financial Statements have been prepared in accordance with GAAP. In our opinion, the accompanying unaudited Condensed Consolidated Financial Statements contain all normal and recurring adjustments necessary for a fair statement of the Company’s financial position as of June 30, 2019, its results of operations for the three and six months ended June 30, 2019, and its cash flows for the six months ended June 30, 2019. The results for the three and six months ended June 30, 2019 are not necessarily indicative of the results to be expected for the year ending December 31, 2019. The Condensed Consolidated Balance Sheet as of December 31, 2018 was derived from our audited financial statements filed with the SEC on April 15, 2019, but is presented as condensed and does not contain all of the footnote disclosures from the annual financial statements.
Revenues and Cost Recognition	Revenues and Cost Recognition Revenues from fixed price and modified fixed price contracts are recognized on the percentage-of-completion method, measured by the relationship of total cost incurred to total estimated contract costs (cost-to-cost method). Contract revenue for long-term construction contracts is based upon management’s estimates of contract values at completion, including revenue for additional work on which the contract value has not been finalized (claims and unapproved change orders) but is considered probable. Changes in job performance, job conditions, and estimated profitability, including those arising from contract penalty provisions and final contract settlements, may result in revisions to estimated costs and income, and are recognized in the period in which the revisions are determined. Provisions for estimated losses on uncompleted contracts are recognized in the period in which such losses are determined. Contract costs include direct labor, material, and subcontractor costs, and those indirect costs related to contract performance, such as indirect labor, supplies, tools, repairs, depreciation, and insurance. Total estimated contract costs are based upon management’s current estimate of total costs at completion. There are two basic types of service contracts: fixed price service contracts which are signed in advance for maintenance, repair and retrofit work over a period of typically one year, and service contracts not signed in advance for similar maintenance, repair and retrofit work performed on an as-needed basis. Fixed price service contracts are generally performed evenly over the contract period, and accordingly, revenue is recognized on a pro rata basis over the life of the contract. Revenues derived from other service contracts are recognized when the services are performed. Expenses related to all service contracts are recognized as services are provided. Costs and estimated earnings in excess of billings on uncompleted contracts reflected in the Condensed Consolidated Financial Statements arise when revenues have been recognized but the amounts cannot be billed under the terms of the contracts. Also included in costs and estimated earnings in excess of billings on uncompleted contracts are amounts the Company seeks or will seek to collect from customers or others for errors or changes in contract specifications or design, contract change orders in dispute or unapproved as to scope and price, or other customer-related causes of unanticipated additional contract costs (claims and unapproved change orders). Claims and unapproved change orders are recorded at estimated net realizable value when realization is probable and can be reasonably estimated. No profit is recognized on the construction costs incurred in connection with claim amounts. Claims and unapproved change orders made by the Company may involve negotiation and, in rare cases, litigation. Claims and unapproved change orders involve the use of estimates, and it is reasonably possible that revisions to the estimated recoverable amounts of recorded claims and unapproved change orders may be made in the near term. Claims against the Company are recognized when a loss is considered probable and amounts are reasonably determinable. Billings in excess of costs and estimated earnings on uncompleted contracts represent billings in excess of revenues recognized. In accordance with industry practice, we classify as current all assets and liabilities relating to the performance of contracts. The terms of our contracts generally range from six months to two years. Selling, general, and administrative costs are charged to expense as incurred. Bidding and proposal costs are also recognized as an expense in the period in which such amounts are incurred.
Reclassifications and Adjustments	Reclassifications and Adjustments Certain reclassifications of prior periods’ data have been made to conform to the current period presentation. The Company reclassified this prior period data as a result of the retrospective adoption on January 1, 2019 of Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) 2016‑18, “Statement of Cash Flows: Restricted Cash.” The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the Company’s Condensed Consolidated Balance Sheets that sum to the total of the same amounts shown in the Condensed Consolidated Statement of Cash Flows: (in thousands) June 30, 2019 December 31, 2018 June 30, 2018 December 31, 2017 Cash and cash equivalents $ 1,011 $ 1,619 $ 256 $ 626 Restricted cash 113 113 113 113 Total cash, cash equivalents and restricted cash $ 1,124 $ 1,732 $ 369 $ 739

Significant Accounting Polici_3

Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2019
Significant Accounting Policies
Reconciliation of Assets from Segment to Consolidated	The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the Company’s Condensed Consolidated Balance Sheets that sum to the total of the same amounts shown in the Condensed Consolidated Statement of Cash Flows: (in thousands) June 30, 2019 December 31, 2018 June 30, 2018 December 31, 2017 Cash and cash equivalents $ 1,011 $ 1,619 $ 256 $ 626 Restricted cash 113 113 113 113 Total cash, cash equivalents and restricted cash $ 1,124 $ 1,732 $ 369 $ 739

Accounts Receivable and Allow_2

Accounts Receivable and Allowance for Doubtful Accounts (Tables)	6 Months Ended
	Jun. 30, 2019
Accounts Receivable and Allowance for Doubtful Accounts
Schedule of Accounts, Notes, Loans and Financing Receivable	Accounts receivable and the allowance for doubtful accounts are comprised of the following: ( in thousands ) June 30, 2019 December 31, 2018 Accounts receivable $ 111,803 $ 106,063 Retainage 31,236 29,867 Allowance for doubtful accounts (278) (243) Accounts receivable, net $ 142,761 $ 135,687

Contracts in Progress (Tables)

Contracts in Progress (Tables)	6 Months Ended
	Jun. 30, 2019
Contracts in Progress
Schedule Of Contracts In Progress	( in thousands ) June 30, 2019 December 31, 2018 Revenue earned on uncompleted contracts $ 765,794 $ 731,923 Less: Billings to date (776,300) (750,068) Net underbilling (overbilling) $ (10,506) (18,145) The above is reflected in the accompanying Condensed Consolidated Balance Sheets as follows: Costs and estimated earnings in excess of billing on uncompleted contracts $ 36,030 $ 32,698 Billings in excess of costs and estimated earnings on uncompleted contracts (46,536) (50,843) Net underbilling (overbilling) $ (10,506) $ (18,145)

Goodwill and Intangibles (Table

Goodwill and Intangibles (Tables)	6 Months Ended
	Jun. 30, 2019
Goodwill and Intangibles
Schedule of Intangible Assets and Goodwill	Goodwill and intangible assets consist of the following: Gross carrying Accumulated Net intangible (in thousands) amount amortization assets June 30, 2019 Amortized intangible assets: Backlog – Construction $ 4,830 $ (4,830) $ — Customer Relationships – Service 4,710 (2,397) 2,313 Favorable Leasehold Interests 530 (200) 330 Total amortized intangible assets 10,070 (7,427) 2,643 Unamortized intangible assets: Trade Name 9,960 — 9,960 Total unamortized intangible assets 9,960 — 9,960 Total amortized and unamortized assets, excluding goodwill $ 20,030 $ (7,427) $ 12,603 Goodwill $ 10,488 $ — $ 10,488 Gross carrying Accumulated Net intangible (in thousands) amount amortization assets December 31, 2018 Amortized intangible assets: Backlog – Construction $ 4,830 $ (4,830) $ — Customer Relationships – Service 4,710 (2,081) 2,629 Favorable Leasehold Interests 530 (166) 364 Total amortized intangible assets 10,070 (7,077) 2,993 Unamortized intangible assets: Trade Name 9,960 — 9,960 Total unamortized intangible assets 9,960 — 9,960 Total amortized and unamortized assets, excluding goodwill $ 20,030 $ (7,077) $ 12,953 Goodwill $ 10,488 $ — $ 10,488

Debt (Tables)

Debt (Tables)	6 Months Ended
	Jun. 30, 2019
Debt
Schedule of Debt	Long-term debt consists of the following obligations as of: June 30, December 31, (in thousands) 2019 2018 Credit Agreement – revolver (1) $ — $ — Bridge Term Loan – term loan payable in quarterly installments of principal, plus interest through April 2019 (1) — 7,736 Credit Agreement – term loan payable in quarterly installments of principal, plus interest through March 2020 (1) — 14,335 2019 Revolving Credit Facility — — 2019 Refinancing Term Loan – term loan payable in quarterly installments of principal, (commencing in September 2020) plus interest through April 2022 40,000 — Long-term portion of 2019 Refinancing Term Loan embedded derivative 177 — Capital leases – collateralized by vehicles, payable in monthly installments of principal, plus interest ranging from 4.95% to 6.1% through 2023 5,587 5,145 Total debt 45,764 27,216 Less - Current portion of long-term debt (2,173) (3,141) Less - Unamortized discount and debt issuance costs (3,608) (461) Long-term debt $ 39,983 $ 23,614 (1) On April 12, 2019, the Company entered into the Refinancing Agreements (as defined below) and used the net proceeds to repay its existing indebtedness under the Credit Agreement (as defined below).
Senior Leverage ratio covenant	The following is a summary of the additional margin and commitment fees payable on the prior revolving credit commitment: Additional Margin for Additional Margin for Level Senior Leverage Ratio Base Rate loans Libor Rate loans Commitment Fee I Greater than or equal to 2.50 to 1.00 3.00 % 4.00 % 0.50 % II Less than 2.50 to 1.00, but greater than or equal to 2.00 to 1.00 2.75 % 3.75 % 0.50 % III Less than 2.00 to 1.00, but greater than or equal to 1.50 to 1.00 2.50 % 3.50 % 0.50 % IV Less than 1.50 to 1.00 2.25 % 3.25 % 0.50 %

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2019
Fair Value Measurements
Schedule of assumptions used within the Black-Scholes-Merton option pricing model to value the Company's warrant liabilities	The table below sets forth the assumptions used within the Black-Scholes-Merton option pricing model to value the Company’s warrant liabilities: Stock price $ 8.13 Exercise price $ 7.63 Time until expiration (years) 4.8 Expected volatility 56.2 % Risk-free interest rate 1.8 % Expected dividend yield 0.0 %
Schedule of level 3 rollforward table	Level 3 rollforward table: (in thousands) Embedded CB Warrants Derivative Liability Liability Fair value, December 31, 2018 $ — $ — Issuances — — Transfers — — Change in fair value — — Fair value,March 31, 2019 — — Issuances 969 388 Transfers — — Change in fair value 103 — Fair value, June 30, 2019 $ 1,072 $ 388

Earnings per Share (Tables)

Earnings per Share (Tables)	6 Months Ended
	Jun. 30, 2019
Earnings per Share
Schedule of earnings per share, basic and diluted	Diluted EPS assumes the dilutive effect of outstanding common stock warrants, UPOs and RSUs, all using the treasury stock method, and the dilutive effect of the Class A Preferred Stock, using the “if-converted” method. Three months ended Six months ended June 30, June 30, (in thousands, except per share amounts) 2019 2018 2019 2018 EPS numerator: Net income (loss) $ (1,504) $ 709 $ 642 $ (1,715) Less: Premium paid on partial preferred redemption — — — 2,219 Less: Undistributed preferred stock dividends — — — (113) Net income (loss) attributable to Limbach Holdings, Inc. common stockholders $ (1,504) $ 709 $ 642 $ (3,821) EPS denominator: Weighted average shares outstanding – basic 7,643 7,543 7,643 7,542 Impact of dilutive securities — 265 74 — Weighted average shares outstanding – diluted 7,643 7,808 7,717 7,542 Basic EPS attributable to common stockholders: Net income (loss) attributable to Limbach Holdings, Inc. common stockholders $ (0.20) $ 0.09 $ 0.08 $ (0.51) Diluted EPS attributable to common stockholders: Net income (loss) attributable to Limbach Holdings, Inc. common stockholders $ (0.20) $ 0.09 $ 0.08 $ (0.51)
Schedule of diluted income (loss) per common share	The following table summarizes the securities that were antidilutive (including warrants, UPOs, RSUs and Preferred Stock after giving effect to their respective conversion to shares of common stock for those units in-the-money, or share equivalents for those units out-of-the-money) and therefore, were not included in the computations of diluted income (loss) per common share: Three months ended Six months ended June 30, June 30, 2019 2018 2019 2018 In-the-money warrants (See Note 8) — — — 277,640 Out-of-the-money warrants (See Note 8) 4,576,799 1,231,119 4,576,799 600,000 Preferred Stock (See Note 9) — — — 34,033 Restricted stock units (RSUs) (See Note 17) (1) 138,782 — 2,867 76,972 In-the-money UPOs (See Note 8) — — — — Out-of-the-money UPOs (See Note 8) 27,360 — 27,360 4,502 Total 4,742,941 1,231,119 4,607,026 993,147 (1) For the three and six months ended June 30, 2019 and 2018, all PRSUs and MRSUs (both as defined below) were not included in the computation of diluted loss per share because the performance and market conditions were not satisfied during the periods and would not be satisfied if the reporting date was at the end of the contingency periods.

Operating Segments (Tables)

Operating Segments (Tables)	6 Months Ended
	Jun. 30, 2019
Operating Segments
Schedule of Segment Reporting Information	Condensed consolidated segment information for the periods presented is as follows: Three months ended June 30, (in thousands) 2019 2018 Statement of Operations Data: Revenue: Construction $ 104,925 $ 113,735 Service 27,828 25,796 Total revenue 132,753 139,531 Gross profit: Construction 10,422 9,501 Service 6,979 6,297 Total gross profit 17,401 15,798 Selling, general and administrative expenses: Construction 8,377 6,696 Service 4,460 3,345 Corporate 4,242 3,644 Total selling, general and administrative expenses 17,079 13,685 Amortization of intangibles 175 336 Operating income (loss) $ 147 $ 1,777 Operating income (loss) for reportable segments $ 147 $ 1,777 Less unallocated amounts: Interest expense, net (1,597) (799) Gain on disposition of property and equipment 9 24 Loss on debt extinguishment (513) — Loss on change in fair value of warrant liability (103) — Total unallocated amounts (2,204) (775) Income (loss) before income taxes $ (2,057) $ 1,002 Other Data: Depreciation and amortization: Construction $ 810 $ 704 Service 223 192 Corporate 427 531 Total other data $ 1,460 $ 1,427 Six months ended June 30, (in thousands) 2019 2018 Statement of Operations Data: Revenue: Construction $ 209,599 $ 210,545 Service 57,105 49,535 Total revenue 266,704 260,080 Gross profit: Construction 23,735 18,772 Service 13,699 10,313 Total gross profit 37,434 29,085 Selling, general and administrative expenses: Construction 15,841 14,455 Service 8,771 7,471 Corporate 8,512 7,425 Total selling, general and administrative expenses 33,124 29,351 Amortization of intangibles 350 671 Operating income (loss) $ 3,960 $ (937) Operating income (loss) for reportable segments $ 3,960 $ (937) Less unallocated amounts: Interest expense, net (2,430) (1,568) Gain on disposition of property and equipment 21 40 Loss on debt extinguishment (513) — Loss on change in fair value of warrant liability (103) — Total unallocated amounts (3,025) (1,528) Income (loss) before income taxes $ 935 $ (2,465) Other Data: Depreciation and amortization: Construction $ 1,590 $ 1,370 Service 429 372 Corporate 854 1,056 Total other data $ 2,873 $ 2,798

Self-Insurance (Tables)

Self-Insurance (Tables)	6 Months Ended
	Jun. 30, 2019
Self-Insurance
Schedule of the self-insurance liability	The components of the self-insurance liability as of June 30, 2019 and December 31, 2018 are as follows: As of As of June 30, December 31, (in thousands) 2019 2018 Current liability — workers’ compensation and general liability $ 487 $ 352 Current liability — medical and dental 424 607 Non-current liability 657 820 Total liability shown in Accrued expenses and other liabilities $ 1,568 $ 1,779 Restricted cash $ 113 $ 113

Management Incentive Plans (Tab

Management Incentive Plans (Tables)	6 Months Ended
	Jun. 30, 2019
Service Based Restricted Stock Units [Member]
Schedule of Nonvested Restricted Stock Units Activity	The following table summarizes our service-based RSU activity for the six months ended June 30, 2019: Weighted-Average Grant Date Awards Fair Value Unvested at December 31, 2018 173,087 $ 13.30 Granted 220,636 6.61 Vested (50,222) 13.31 Forfeited (5,418) 9.17 Unvested at June 30, 2019 338,083 $ 9.00
Performance Based Restricted Stock Units [Member]
Schedule of Nonvested Restricted Stock Units Activity	The following table summarizes our PRSU activity for the six months ended June 30, 2019: Weighted-Average Grant Date Awards Fair Value Unvested at December 31, 2018 124,057 $ 13.34 Granted — — Vested — — Forfeited (2,750) 13.39 Unvested at June 30, 2019 121,307 $ 13.34
Market Based Awards [Member]
Schedule of Nonvested Restricted Stock Units Activity	The following table summarizes our market-based RSU (“MRSUs”) activity for the six months ended June 30, 2019: Weighted-Average Grant Date Awards Fair Value Unvested at December 31, 2018 140,500 $ 6.58 Granted — — Vested — — Forfeited (3,000) 6.58 Unvested at June 30, 2019 137,500 $ 6.58

Significant Accounting Polici_4

Significant Accounting Policies (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Significant Accounting Policies
Cash and cash equivalents	$ 1,011	$ 1,619	$ 256	$ 626
Restricted cash	113	113	113	113
Total cash, cash equivalents and restricted cash	$ 1,124	$ 1,732	$ 369	$ 739

Accounts Receivable and Allow_3

Accounts Receivable and Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Accounts Receivable and Allowance for Doubtful Accounts
Accounts receivable	$ 111,803	$ 106,063
Retainage	31,236	29,867
Allowance for doubtful accounts	(278)	(243)
Accounts receivable, net	$ 142,761	$ 135,687

Contracts in Progress (Details)

Contracts in Progress (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
Contracts in Progress
Revenue earned on uncompleted contracts	$ 765,794	$ 731,923
Less: Billings to date	(776,300)	(750,068)
Net underbilling (overbilling)	(10,506)	(18,145)
Costs and estimated earnings in excess of billing on uncompleted contracts	36,030	32,698
Billings in excess of costs and estimated earnings on uncompleted contracts	(46,536)	(50,843)
Net underbilling (overbilling)	$ (10,506)	$ (18,145)

Contracts in Progress (Detail_2

Contracts in Progress (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Subcontract Payable Retainage	$ 11.7	$ 11.7	$ 13
Service project
Property, Plant and Equipment [Line Items]
Gross profit write Up	0.3
Mid-Atlantic project
Property, Plant and Equipment [Line Items]
Gross profit write Up		0.3
Southern California Service Project
Property, Plant and Equipment [Line Items]
Revision In Contract Estimates Recorded Project Write Down		0.3
Construction project
Property, Plant and Equipment [Line Items]
Gross profit write Up	0.3
Michigan project
Property, Plant and Equipment [Line Items]
Gross profit write Up		1.4
Southern California Construction Project
Property, Plant and Equipment [Line Items]
Gross profit write Up	$ 1.9
Six Projects [Member] | Construction project
Property, Plant and Equipment [Line Items]
Gross profit write Up		3
Three Projects [Member] | Mid-Atlantic project
Property, Plant and Equipment [Line Items]
Gross profit write Up		1
Seven Projects [Member] | Construction project
Property, Plant and Equipment [Line Items]
Revision In Contract Estimates Recorded Project Write Down		3.5
Four projects [Member] | Southern California Construction Project
Property, Plant and Equipment [Line Items]
Revision In Contract Estimates Recorded Project Write Down		2.2
One Project [Member] | Mid-Atlantic project
Property, Plant and Equipment [Line Items]
Revision In Contract Estimates Recorded Project Write Down		$ 0.5

Goodwill and Intangibles (Detai

Goodwill and Intangibles (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 10,070	$ 10,070
Finite-Lived Intangible Assets, Accumulated Amortization	(7,427)	(7,077)
Finite-Lived Intangible Assets, Net	2,643	2,993
Indefinite-Lived Intangible Assets (Excluding Goodwill)	9,960	9,960
Intangible Assets Amortized Excluding Goodwill	9,960	9,960
Intangible Assets, Gross (Excluding Goodwill)	20,030	20,030
Intangible Assets, Net (Excluding Goodwill)	12,603	12,953
Goodwill, Gross	10,488	10,488
Goodwill, Impaired, Accumulated Impairment Loss	0	0
Goodwill	10,488	10,488
BackLog - Construction [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	4,830	4,830
Finite-Lived Intangible Assets, Accumulated Amortization	(4,830)	(4,830)
Finite-Lived Intangible Assets, Net	0	0
Customer Relationships - Service [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	4,710	4,710
Finite-Lived Intangible Assets, Accumulated Amortization	(2,397)	(2,081)
Finite-Lived Intangible Assets, Net	2,313	2,629
Favorable Leasehold Interests [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	530	530
Finite-Lived Intangible Assets, Accumulated Amortization	(200)	(166)
Finite-Lived Intangible Assets, Net	330	364
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	0	0
Finite-Lived Intangible Assets, Accumulated Amortization	0	0
Indefinite-Lived Intangible Assets (Excluding Goodwill)	9,960	9,960
Intangible Assets Amortized Excluding Goodwill	$ 9,960	$ 9,960

Goodwill and Intangibles (Det_2

Goodwill and Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Finite-Lived Intangible Assets [Line Items]
Amortization of Intangible Assets	$ 175	$ 336	$ 350	$ 671
Successor [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization of Intangible Assets	$ 100	$ 300	$ 400	$ 700

Debt (Details)

Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Total debt	$ 45,764	$ 27,216
Less - Current portion of long-term debt	(2,173)	(3,141)
Less - Unamortized discount and debt issuance costs	(3,608)	(461)
Long-term debt	39,983	23,614
Bridge Loan
Total debt		7,736
Capital Lease Obligations
Total debt	5,587	5,145
2019 Revolving Credit Facility
Total debt		0
2019 Refinancing Term Loan
Total debt	40,000	0
2019 Refinancing Term Loan Embedded Derivative [Member]
Total debt	$ 177	0
Credit Agreement
Total debt		0
Credit Agreement | Loans Payable
Total debt		$ 14,335

Debt - Revolving Credit Commitm

Debt - Revolving Credit Commitment (Details)	6 Months Ended
	Jun. 30, 2019
Level One
Debt Instrument [Line Items]
Line of Credit Facility, Commitment Fee Percentage	0.50%
Level One | Base Rate
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	3.00%
Level One | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	4.00%
Level Two
Debt Instrument [Line Items]
Line of Credit Facility, Commitment Fee Percentage	0.50%
Level Two | Base Rate
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.75%
Level Two | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	3.75%
Level Three
Debt Instrument [Line Items]
Line of Credit Facility, Commitment Fee Percentage	0.50%
Level Three | Base Rate
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.50%
Level Three | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	3.50%
Level Four
Debt Instrument [Line Items]
Line of Credit Facility, Commitment Fee Percentage	0.50%
Level Four | Base Rate
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.25%
Level Four | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	3.25%

Debt - Additional Information (

Debt - Additional Information (Details)	Jan. 12, 2018USD ($)shares	Jul. 14, 2017shares	Jul. 31, 2021	Sep. 30, 2020USD ($)	Sep. 30, 2019	Jun. 30, 2019USD ($)$ / sharesshares	Jul. 20, 2016USD ($)	Sep. 30, 2019	Jun. 30, 2019USD ($)$ / sharesshares	Jun. 30, 2019USD ($)$ / sharesshares	Jun. 30, 2018USD ($)	Apr. 12, 2019USD ($)	Dec. 31, 2018USD ($)	Nov. 30, 2018USD ($)	Aug. 13, 2018	Mar. 21, 2018USD ($)	Dec. 31, 2017USD ($)
Debt Instrument [Line Items]
Stock Repurchased During Period, Shares | shares		120,000
Debt Instrument, Maturity Date, Description										Loans under the Credit Agreement bore interest, at the Borrower's option, at either Adjusted LIBOR ("Eurodollar") or a Base Rate, in each case, plus an applicable margin. With respect to the Bridge Term Loan, from January 12, 2018 to, but excluding, July 12, 2018 (the six-month anniversary of the loan), the applicable margin with respect to any Base Rate loans was 4.00% per annum and with respect to any Eurodollar loan was 5.00% per annum. From July 12, 2018 to, but excluding, the 12-month anniversary thereof, the applicable margin with respect to any Base Rate loan was 4.50% per annum and with respect to any Eurodollar loan was 5.50% per annum. From the 12-month anniversary of January 12, 2018 and all times thereafter, the applicable margin with respect to any Base Rate loan was 5.00% per annum and with respect to a Eurodollar loan was 6.00% per annum
Debt Instrument, Repurchased Face Amount	$ 10,000,000
Dividends Payable	900,000
Long-term Debt						$ 45,764,000			$ 45,764,000	$ 45,764,000			$ 27,216,000
Minimum Fixed Charge Ratio Minimum Requirement											1.15
Debt Instrument, Payment Terms										Mandatory prepayments were required upon the occurrence of certain events, including, among other things and subject to certain exceptions, equity issuances, changes of control of the Company, certain debt issuances, assets sales and excess cash flow. The Company could voluntarily prepay the loans at any time subject to the limitations set forth in the Credit Agreement
Debt Instrument, Covenant Description										(x) the Company shall be required to pay the post-closing fee pursuant to the terms of the Origination Agent Fee Letter (as defined in the 2019 Refinancing Agreement) and (y) the applicable margin shall be increased by 1.00 % per annum for the period from January 1, 2020 until the date at which the material weakness is no longer disclosed or required to be disclosed in the Company's SEC filings or audited financial statements of the Company or related auditor's reports.
Minimum Fixed Charge Coverage Ratio For First Quarter															1.15
Minimum Fixed Charge Coverage Ratio Thereafter															1.25
Amortization of Debt Issuance Costs										$ 510,000	$ 144,000
Percentage of number of shares										2.00%
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares						$ 11.50			$ 11.50	$ 11.50
Debt issuance costs						$ 3,608,000			$ 3,608,000	$ 3,608,000			461,000
2019 Refinancing Agreement
Debt Instrument [Line Items]
Debt Instrument, Face Amount												$ 40,000,000
Short-term Debt, Refinanced, Description										On April 12, 2019 (the "Refinancing Closing Date"), LFS entered into a financing agreement (the "2019 Refinancing Agreement") with the lenders thereto and Cortland Capital Market Services LLC, as collateral agent and administrative agent and CB Agent Services LLC, as origination agent ("CB"). The 2019 Refinancing Agreement consists of (i) a $40.0 million term loan (the "2019 Refinancing Term Loan") and (ii) a new $25.0 million multi-draw delayed draw term loan (the "2019 Delayed Draw Term Loan" and, collectively with the 2019 Refinancing Term Loan, the
Debt Instrument, Basis Spread on Variable Rate										3.00%
Amortization of Debt Issuance Costs									$ 200,000
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares						$ 7.63			$ 7.63	$ 7.63
Class of Warrant or Right, Number of Securities Called by Warrants or Rights | shares						263,314			263,314	263,314
Debt issuance costs						$ 2,500,000			$ 2,500,000	$ 2,500,000
Interest Expense									100,000
Debt Discount						1,300,000			1,300,000	1,300,000
Other Expenses For Change In Fair Values Of CB Warrants Liability									100,000
Other Expenses For Change In Fair Values Of Embedded Derivative Liability									0
Amount drawn						$ 0			$ 0	$ 0
Effective interest rate						10.54%			10.54%	10.54%
Applicable interest to the lenders term										19 months
Premium on prepayments term										18 months
2019 Refinancing Agreement | Other long-term liabilities [Member]
Debt Instrument [Line Items]
Embedded derivative liability						$ 400,000			$ 400,000	$ 400,000
Fair values of the CB Warrants liability						900,000			900,000	900,000
2019 Refinancing Agreement | Accrued expenses and other current liabilities [Member]
Debt Instrument [Line Items]
Current portion of the embedded derivative liability						200,000			200,000	200,000
2019 Refinancing Agreement | Long-term Debt [Member]
Debt Instrument [Line Items]
Long-term portion of embedded derivative liability						200,000			200,000	$ 200,000
2019 ABL Credit Agreement
Debt Instrument [Line Items]
Debt Instrument, Covenant Description										(1) a minimum EBITDA of $6.5 million for the fourth quarter of 2018, (2) a fixed charge coverage ratio not less than 1.10 for each fiscal quarter ending on or after March 31, 2019 (which was decreased from 1.15 for the fiscal quarters ending on June 30, 2018 through December 31, 2018) and (3) unfinanced capital expenditures not to exceed $1.0 million for each fiscal quarter ending March 31, 2019, June 30, 2019, and September 30, 2019; no unfinanced capital expenditures for the fiscal quarter ending December 31, 2019 and total unfinanced capital expenditures not to exceed $3.0 million for the fiscal year ended December 31, 2019; and no unfinanced capital expenditures
Debt Instrument, Basis Spread on Variable Rate										3.00%
Amortization of Debt Issuance Costs									100,000
Debt Instrument, Interest Rate Terms										The interest rate on borrowings under the 2019 ABL Credit Agreement is, at the Borrowers' option, either LIBOR (with a 2.0% floor) plus an applicable margin ranging from 3.00% to 3.50% or a base rate (with a 3.0% minimum) plus an applicable margin ranging from 2.00% to 2.50%.
Debt issuance costs						$ 900,000			$ 900,000	$ 900,000
Minimum
Debt Instrument [Line Items]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage										0.25%
Minimum | 2019 Refinancing Agreement
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage						7.00%			7.00%	7.00%
Leverage Ratio			1.00%			1.00%
Minimum | 2019 ABL Credit Agreement
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate										2.00%
Debt Instrument, Interest Rate, Stated Percentage						3.00%			3.00%	3.00%
Leverage Ratio					1.00%
Maximum
Debt Instrument [Line Items]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage										0.375%
Maximum | 2019 Refinancing Agreement
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage						8.00%			8.00%	8.00%
Leverage Ratio			2.00%			4.25%		4.00%
Maximum | 2019 ABL Credit Agreement
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate										2.50%
Debt Instrument, Interest Rate, Stated Percentage						3.50%			3.50%	3.50%
Leverage Ratio					4.00%
Bridge Loan
Debt Instrument [Line Items]
Debt Instrument, Face Amount	9,100,000
Debt Instrument, Periodic Payment	250,000
Long-term Debt													7,736,000
Capital Lease Obligations
Debt Instrument [Line Items]
Long-term Debt						$ 5,587,000			$ 5,587,000	$ 5,587,000			5,145,000
Capital Lease Obligations | Minimum
Debt Instrument [Line Items]
Interest rate (as a percent)										4.95%
Capital Lease Obligations | Maximum
Debt Instrument [Line Items]
Interest rate (as a percent)										6.10%
London Interbank Offered Rate (LIBOR) | 2019 Refinancing Agreement
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate										2.00%
London Interbank Offered Rate (LIBOR) | 2019 ABL Credit Agreement
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate										2.00%
Scenario, Forecast | 2019 Refinancing Agreement
Debt Instrument [Line Items]
Amortization of Debt Issuance Costs				$ 1,000,000
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage				2.00%
Scenario, Forecast | Minimum | 2019 ABL Credit Agreement
Debt Instrument [Line Items]
Leverage Ratio			1.00%
Scenario, Forecast | Maximum | 2019 ABL Credit Agreement
Debt Instrument [Line Items]
Leverage Ratio			1.75%
Credit Agreement revolver
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity						20,000,000			20,000,000	$ 20,000,000			22,500,000	$ 25,000,000
Credit Agreement revolver | 2019 Refinancing Agreement
Debt Instrument [Line Items]
Amount outstanding						0			0	0
Credit Agreement revolver | 2019 ABL Credit Agreement
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity						15,000,000			15,000,000	15,000,000
Line of Credit Facility, Current Borrowing Capacity						14,000,000			14,000,000	14,000,000
Line Of Credit Facility Reserved Borrowing Capacity						1,000,000			1,000,000	1,000,000
Letter of Credit
Debt Instrument [Line Items]
Long-term Debt						$ 3,400,000			$ 3,400,000	$ 3,400,000			3,400,000			$ 8,000,000	$ 5,000,000
Credit Agreement
Debt Instrument [Line Items]
Long-term Debt													$ 0
Credit Agreement | Bridge Loan
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount	10,000,000
Dividends Payable	$ 900,000
Loans Payable | Senior Credit Facility
Debt Instrument [Line Items]
Debt Instrument, Periodic Payment, Principal							$ 750,000
Senior Credit Facility Agreement | Credit Agreement revolver
Debt Instrument [Line Items]
Debt Instrument, Face Amount							24,000,000
Senior Credit Facility Agreement | Loans Payable
Debt Instrument [Line Items]
Debt Instrument, Face Amount							25,000,000
Debt Instrument, Periodic Payment, Principal							$ 900,000
Preferred Class A
Debt Instrument [Line Items]
Stock Repurchased During Period, Shares | shares	280,000

Equity (Details)

Equity (Details) - USD ($)	1 Months Ended				3 Months Ended	6 Months Ended
	Jan. 08, 2018	Jan. 08, 2018	Dec. 07, 2016	Jul. 21, 2014	Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018	Jul. 15, 2014
Class of Stock [Line Items]
Common Stock, Shares Authorized					100,000,000	100,000,000	100,000,000
Common Stock, Par or Stated Value Per Share					$ 0.0001	$ 0.0001	$ 0.0001
Preferred Stock, Shares Authorized					1,000,000	1,000,000
Preferred Stock, Par or Stated Value Per Share					$ 0.0001	$ 0.0001
Class of Warrant or Right, Outstanding					4,576,799	4,576,799
Class of Warrant or Right, Exercise Price of Warrants or Rights					$ 11.50	$ 11.50
Shares reserved for future issuance					1,150,000	1,150,000
Unit Purchase Options
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				300,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period			282,900
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number					17,100	17,100	17,100
RSU | 2016 Omnibus Incentive Plan
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized					350,000
Public warrants
Class of Stock [Line Items]
Stock Issued During Period, Value, New Issues						$ 4,600,000
Sponsor Warrants
Class of Stock [Line Items]
Class of Warrant or Right, Outstanding					198,000	198,000
Class of Warrant or Right, Exercise Price of Warrants or Rights For Half Share					$ 5.75	$ 5.75
Class of Warrant or Right, Exercise Price of Warrants or Rights					$ 11.50	$ 11.50
Fifteen Dollar Exercise Price Warrants
Class of Stock [Line Items]
Class of Warrant or Right, Outstanding					600,000	600,000
Class of Warrant or Right, Exercise Price of Warrants or Rights					$ 15	$ 15
Merger Warrants
Class of Stock [Line Items]
Class of Warrant or Right, Outstanding					631,119	631,119
Class of Warrant or Right, Exercise Price of Warrants or Rights					$ 12.50	$ 12.50
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	49,604
Additional Merger Warrants
Class of Stock [Line Items]
Class of Warrant or Right, Outstanding					946,680	946,680
Class of Warrant or Right, Exercise Price of Warrants or Rights					$ 11.50	$ 11.50
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	33,069
Predecessor | Public warrants
Class of Stock [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights					15	15
Predecessor | Sponsor Warrants
Class of Stock [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights								$ 15
Common Stock
Class of Stock [Line Items]
Stock-based compensation (in shares)		10,627
Common Stock | Unit Purchase Options
Class of Stock [Line Items]
Stock-based compensation (in shares)			121,173
Warrant
Class of Stock [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights					$ 11.50	$ 11.50

Cumulative Redeemable Convert_2

Cumulative Redeemable Convertible Preferred Stock (Details) - USD ($) $ in Millions	Jan. 12, 2018	Jul. 14, 2017	Jul. 20, 2016
Class of Stock [Line Items]
Convertible Preferred Stock, Terms of Conversion			Each share of Preferred Stock was convertible (at the holder's election) into two shares of the Company's common stock (as may be adjusted for any stock splits, reverse stock splits or similar transactions), representing a conversion price of $12.50 per share
Redeemable Preferred Stock Description		) the Company repurchased from 1347 Investors a total of 120,000 shares of the Preferred Stock for an aggregate sum of $4.1 million in cash, (b) for a period of six months after such repurchase, the Company had the right to repurchase from 1347 Investors, in one or more transactions, all or a portion of the remaining 280,000 shares of Preferred Stock owned by 1347 Investors for a purchase price equal to 130% of the liquidation value per share plus 130% of any and all accrued but unpaid dividends thereon as of the date of closing of the purchase of such shares and (c) 1347 Investors would not, with respect to the 509,500 shares of common stock held in escrow
Stock Repurchased During Period, Shares		120,000
Payments for Repurchase of Preferred Stock and Preference Stock		$ 4.1
Common Stock Shares Held In Escrow Shares		509,500
Debt Instrument, Repurchased Face Amount	$ 10
Dividends Payable	0.9
Debt Instrument, Unamortized Premium	$ 2.2
Preferred Stock
Class of Stock [Line Items]
Stock Repurchased During Period, Shares	280,000
Redeemable Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Dividend Payment Terms			preferential dividends at a rate of: (i) 8% per annum in years one through three from issuance; (ii) 10% per annum in years four through five from issuance; and (iii) 12% per annum thereafter, payable in equal quarterly installments
Series A Preferred Stock [Member]
Class of Stock [Line Items]
Stock Issued During Period, Shares, Acquisitions			400,000

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) $ in Millions	Jun. 30, 2019USD ($)
2019 Revolving Credit Facility
Debt Instrument, Fair Value Disclosure	$ 40

Fair Value Measurement - Assump

Fair Value Measurement - Assumptions (Tables) - Black-Scholes-Merton option pricing model [Member] - Warrant - Level 3 [Member]	Jun. 30, 2019RateYitem
Stock price [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Value of input	8.13
Exercise Price [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Value of input	7.63
Time until expiration (years) [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Value of input | Y	4.8
Expected volatility [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Value of input	56.2
Risk-free interest rate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Value of input | Rate	1.8
Expected dividend yield [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Value of input	0

Fair Value Measurements - Level

Fair Value Measurements - Level 3 Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2019
2019 Refinancing Agreement
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Percent of weakness fee			1.00%
Percent of increase in applicable margin			1.00%
CB Warrants Liability [Member]
Level 3 rollforward table
Fair value, beginning	$ 0	$ 0	$ 0
Issuances	969	0
Transfers	0	0
Change in fair value	103	0
Fair value, ending	1,072	0	1,072
Embedded Derivative Liability [Member]
Level 3 rollforward table
Fair value, beginning	0	0	0
Issuances	388	0
Transfers	0	0
Change in fair value	0	0
Fair value, ending	$ 388	$ 0	$ 388

Earnings per Share (Details)

Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
EPS numerator:
Net income (loss)	$ (1,504)	$ 2,146	$ 709	$ (2,424)	$ 642	$ (1,715)
Less: Premium paid on partial preferred redemption	0		0		0	2,219
Less: Undistributed preferred stock dividends	0		0		0	(113)
Net income (loss) attributable to Limbach Holdings, Inc. common stockholders	$ (1,504)		$ 709		$ 642	$ (3,821)
EPS denominator:
Weighted average shares outstanding - basic	7,643,133		7,542,503		7,643,133	7,541,965
Impact of dilutive securities	0		265,000		74,000	0
Weighted average shares outstanding - diluted	7,643,133		7,807,768		7,717,484	7,541,965
Basic EPS attributable to common stockholders:
Net earnings (loss) attributable to Limbach Holdings, Inc. common stockholders	$ (0.20)		$ 0.09		$ 0.08	$ (0.51)
Diluted EPS attributable to common stockholders:
Net earnings (loss) attributable to Limbach Holdings, Inc. common stockholders	$ (0.20)		$ 0.09		$ 0.08	$ (0.51)

Earnings per Share - Anti Dilut

Earnings per Share - Anti Dilutive Securities (Details) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	4,742,941	1,231,119	4,607,026	993,147
In the money warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0	0	0	277,640
Out of the money warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	4,576,799	1,231,119	4,576,799	600,000
Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0	0	0	34,033
Restricted Stock Units (RSUs)
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	138,782	0	2,867	76,972
In the money UPOs
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0	0	0	0
Out of the money UPOs
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	27,360	0	27,360	4,502

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Income Taxes
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	26.90%	29.20%	31.30%	30.40%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent			21.00%
Valuation allowance	$ 0		$ 0		$ 0
Uncertain tax positions	$ 0		$ 0		$ 0

Operating Segments (Details)

Operating Segments (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)segment	Jun. 30, 2018USD ($)
Segment information
Total revenue	$ 132,753	$ 139,531	$ 266,704	$ 260,080
Total gross profit	17,401	15,798	37,434	29,085
Total selling, general and administrative expenses	17,079	13,685	33,124	29,351
Amortization of intangibles	175	336	350	671
Operating income (loss)	147	1,777	3,960	(937)
Operating income (loss) for reportable segments	147	1,777	3,960	(937)
Interest expense, net	(1,597)	(799)	(2,430)	(1,568)
Gain on disposition of property and equipment	9	24	21	40
Loss on debt extinguishment	(513)		(513)
Loss on change in fair value of warrant liability	(103)		(103)
Total unallocated amounts	(2,204)	(775)	(3,025)	(1,528)
Income (loss) before income taxes	(2,057)	1,002	935	(2,465)
Depreciation and amortization	1,460	1,427	$ 2,873	2,798
Number of Operating Segments | segment			2
Construction
Segment information
Total revenue	104,925	113,735	$ 209,599	210,545
Total gross profit	10,422	9,501	23,735	18,772
Total selling, general and administrative expenses	8,377	6,696	15,841	14,455
Depreciation and amortization	810	704	1,590	1,370
Service
Segment information
Total revenue	27,828	25,796	57,105	49,535
Total gross profit	6,979	6,297	13,699	10,313
Total selling, general and administrative expenses	4,460	3,345	8,771	7,471
Depreciation and amortization	223	192	429	372
Corporate Segment
Segment information
Total selling, general and administrative expenses	4,242	3,644	8,512	7,425
Depreciation and amortization	$ 427	$ 531	$ 854	$ 1,056

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($) $ in Thousands	Oct. 12, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Loss Contingencies [Line Items]
Operating Leases, Rent Expense		$ 1,300	$ 1,100	$ 2,700	$ 2,200
Long-term Debt		45,764		45,764		$ 27,216
Litigation Settlement, Amount Awarded to Other Party	$ 30,000
Other Accrued Liabilities, Current						30,000
Surety Bond [Member]
Loss Contingencies [Line Items]
Long-term Debt		$ 98,300		$ 98,300		$ 134,200

Self-Insurance (Details)

Self-Insurance (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Self-Insurance
Current liability - workers' compensation and general liability	$ 487	$ 352
Current liability - medical and dental	424	607
Non-current liability	657	820
Total liability shown in Accrued expenses and other liabilities	1,568	1,779
Restricted cash	$ 113	$ 113

Self-Insurance - Additional Inf

Self-Insurance - Additional Information (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2019USD ($)
Self-Insurance
Payment To Acquire Workers' Compensation And General Liability Insurance	$ 250
Malpractice Insurance, Annual Coverage Limit	$ 4,200

Backlog (Details)

Backlog (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Construction
Estimated Revenue From Uncompleted Contract	$ 536.8
Construction | Predecessor
Estimated Revenue From Uncompleted Contract		$ 505.5
Service
Estimated Revenue From Uncompleted Contract	$ 49.4
Service | Predecessor
Estimated Revenue From Uncompleted Contract		$ 54.2

Management Incentive Plans (Det

Management Incentive Plans (Details)	6 Months Ended
	Jun. 30, 2019$ / sharesshares
Service Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested, Awards | shares	173,087
Granted, Awards | shares	220,636
Vested, Awards | shares	(50,222)
Forfeited, Awards | shares	(5,418)
Unvested, Awards | shares	338,083
Unvested, Weighted-Average Grant Date Fair Values | $ / shares	$ 13.30
Granted, Weighted-Average Grant Date Fair Values | $ / shares	6.61
Vested, Weighted-Average Grant Date Fair Values | $ / shares	13.31
Forfeited, Weighted-Average Grant Date Fair Values | $ / shares	9.17
Unvested, Weighted-Average Grant Date Fair Values | $ / shares	$ 9
Performance Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested, Awards | shares	124,057
Granted, Awards | shares	0
Vested, Awards | shares	0
Forfeited, Awards | shares	(2,750)
Unvested, Awards | shares	121,307
Unvested, Weighted-Average Grant Date Fair Values | $ / shares	$ 13.34
Granted, Weighted-Average Grant Date Fair Values | $ / shares	0
Vested, Weighted-Average Grant Date Fair Values | $ / shares	0
Forfeited, Weighted-Average Grant Date Fair Values | $ / shares	13.39
Unvested, Weighted-Average Grant Date Fair Values | $ / shares	$ 13.34
Market Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested, Awards | shares	140,500
Granted, Awards | shares	0
Vested, Awards | shares	0
Forfeited, Awards | shares	(3,000)
Unvested, Awards | shares	137,500
Unvested, Weighted-Average Grant Date Fair Values | $ / shares	$ 6.58
Granted, Weighted-Average Grant Date Fair Values | $ / shares	0
Vested, Weighted-Average Grant Date Fair Values | $ / shares	0
Forfeited, Weighted-Average Grant Date Fair Values | $ / shares	6.58
Unvested, Weighted-Average Grant Date Fair Values | $ / shares	$ 6.58

Management Incentive Plans - Ad

Management Incentive Plans - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation	$ 882	$ 1,121
Common Stock, Capital Shares Reserved for Future Issuance	1,150,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	1 year 2 months 9 days
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options	$ 1,600
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 200	$ 300
Service Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	220,636
Omnibus Incentive Plan 2016 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance	1,150,000
Omnibus Incentive Plan 2016 [Member] | Service Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	220,636