1
 
                                                                    EXHIBIT 99.1
 
                         FORM OF LETTER OF TRANSMITTAL
 
                            AMERICAN ECO CORPORATION
                             LETTER OF TRANSMITTAL
                                      FOR
                               OFFER TO EXCHANGE
                     9 5/8% SERIES B SENIOR NOTES DUE 2008
                              FOR ALL OUTSTANDING
                     9 5/8% SERIES A SENIOR NOTES DUE 2008
 
        THE EXCHANGE OFFER WILL EXPIRE AT 5:00 P.M., NEW YORK CITY TIME,
                   ON             , 1998, UNLESS EXTENDED BY
               AMERICAN ECO CORPORATION (THE "EXPIRATION DATE").
 
                               THE EXCHANGE AGENT
                           FOR THE EXCHANGE OFFER IS:
                      STATE STREET BANK AND TRUST COMPANY
 

                                            
                                For Information by Telephone:
                                       (800) 531-0368
 
       By Registered or Certified Mail:            By Hand or Overnight Delivery Service:
     State Street Bank and Trust Company            State Street Bank and Trust Company
          Corporate Trust Department                     Corporate Trust Department
                 P.O. Box 778                                   Fourth Floor
            Boston, MA 02102-0078                         Two International Place
                                                              Boston, MA 02110

 
          By Facsimile Transmission (for Eligible Institutions only):
                                 (617) 664-5739
 
                            (Facsimile Confirmation)
                                 (617) 664-5456
 
(Originals of all documents sent by facsimile should be sent promptly by
registered or certified mail, by hand, or by overnight delivery service.)
 
     DELIVERY OF THIS LETTER OF TRANSMITTAL TO AN ADDRESS OTHER THAN AS SET
FORTH ABOVE OR TRANSMISSION OF INSTRUCTIONS VIA A FACSIMILE TRANSMISSION TO A
NUMBER OTHER THAN AS SET FORTH ABOVE WILL NOT CONSTITUTE A VALID DELIVERY. THE
INSTRUCTIONS CONTAINED HEREIN SHOULD BE READ CAREFULLY BEFORE THIS LETTER OF
TRANSMITTAL IS COMPLETED.
 
     The undersigned hereby acknowledges receipt and review of the Prospectus
dated             , 1998 (the "Prospectus") of American Eco Corporation, an
Ontario, Canada corporation (the "Company"), and the subsidiary guarantors
referred to therein (collectively, the "Guarantors"), and this Letter of
Transmittal (the "Letter of Transmittal"), which together describe the Company's
offer (the "Exchange Offer") to exchange its 9 5/8% Series B Senior Notes due
2008 (the "Exchange Notes"), which have been registered under the Securities Act
of 1933, as amended (the "Securities Act"), for a like principal amount of its
issued and outstanding 9 5/8% Series A Senior Notes due 2008 (the "Original
Notes"). Capitalized terms used but not defined herein have the respective
meaning given to them in the Prospectus.
 
                                       -1-
   2
 
     The Company reserves the right, at any time or from time to time, to extend
the Exchange Offer at its discretion, in which event the term "Expiration Date"
shall mean the latest date to which the Exchange Offer is extended. The Company
shall notify the Exchange Agent and each registered holder of the Original Notes
of any extension by oral or written notice prior to 9:00 a.m., New York City
time, on the next business day after the previously scheduled Expiration Date.
 
     This Letter of Transmittal is to be used by a holder of Original Notes if
original Original Notes, if available, are to be forwarded herewith. An Agent's
Message (as defined in the next sentence) is to be used if delivery of Original
Notes is to be made by book-entry transfer to the account maintained by the
Exchange Agent at the Depository Trust Company (the "Book-Entry Transfer
Facility") pursuant to the procedures set forth in the Prospectus under the
caption "The Exchange Offer -- Terms of the Exchange Offer -- Procedures for
Tendering." The term "Agent's Message" means a message, transmitted by the
Book-Entry Transfer Facility and received by the Exchange Agent and forming a
part of the confirmation of a book-entry transfer ("Book-Entry Confirmation"),
which states that the Book-Entry Transfer Facility has received an express
acknowledgment from a participant tendering Original Notes which are the subject
of such Book-Entry Confirmation and that such participant has received and
agrees to be bound by the terms of the Letter of Transmittal and that the
Company may enforce such agreement against such participant. Holders of Original
Notes whose Original Notes are not immediately available, or who are unable to
deliver their Original Notes and all other documents required by this Letter of
Transmittal to the Exchange Agent on or prior to the Expiration Date, or who are
unable to complete the procedure for book-entry transfer on a timely basis, must
tender their Original Notes according to the guaranteed delivery procedures set
forth in the Prospectus under the caption "The Exchange Offer -- Terms of the
Exchange Offer -- Guaranteed Delivery Procedures." See Instruction 2. Delivery
of documents to the Book-Entry Transfer Facility does not constitute delivery to
the Exchange Agent.
 
     The term "holder" with respect to the Exchange Offer means any person in
whose name Original Notes are registered on the books of the Company or any
other person who has obtained a properly completed bond power from the
registered holder. The undersigned has completed, executed and delivered this
Letter of Transmittal to indicate the action the undersigned desires to take
with respect to the Exchange Offer. Holders who wish to tender their Original
Notes must complete this Letter of Transmittal in its entirety.
 
     PLEASE READ THE ENTIRE LETTER OF TRANSMITTAL AND THE PROSPECTUS CAREFULLY
BEFORE CHECKING ANY BOX BELOW.
 
     THE INSTRUCTIONS INCLUDED WITH THIS LETTER OF TRANSMITTAL MUST BE FOLLOWED.
QUESTIONS AND REQUESTS FOR ASSISTANCE OR FOR ADDITIONAL COPIES OF THE PROSPECTUS
AND THIS LETTER OF TRANSMITTAL MAY BE DIRECTED TO THE EXCHANGE AGENT.
 
                                       -2-
   3
 
     List below the Original Notes to which this Letter of Transmittal relates.
If the space below is inadequate, list the registered numbers and principal
amount on a separate signed schedule and affix the list to this Letter of
Transmittal.
 

                                                                                
- ------------------------------------------------------------------------------------------------------------
                                   DESCRIPTION OF ORIGINAL NOTES TENDERED
- ------------------------------------------------------------------------------------------------------------
 NAME(S) AND ADDRESS(ES) OF REGISTERED OWNER(S)
 AS (IT/THEY) APPEAR(S) ON THE 9 5/8% SERIES A
                  SENIOR NOTES                                   AGGREGATE PRINCIPAL AMOUNT
        DUE 2008 (THE "ORIGINAL NOTES")                         REPRESENTED BY ORIGINAL NOTES
- ------------------------------------------------------------------------------------------------------------
                                                     CERTIFICATE          AMOUNT OF
                                                     NUMBER(S)*        ORIGINAL NOTES     PRINCIPAL AMOUNT
                                                 OF ORIGINAL NOTES*       TENDERED            TENDERED
                                                 ------------------------------------------------------
 
                                                 ------------------------------------------------------
 
                                                 ------------------------------------------------------
 
                                                 ------------------------------------------------------
 
                                                 ------------------------------------------------------
                                                  TOTAL PRINCIPAL**
- ------------------------------------------------------------------------------------------------------------
  * Need not be completed by book-entry holders.
 ** Unless otherwise indicated, any tendering holder of Original Notes will be deemed to have tendered the
    entire aggregate principal amount represented by such Original Notes. All tenders must be in integral
    multiples of $1,000.
- ------------------------------------------------------------------------------------------------------------

 
 (If additional space is required, attach a continuation sheet in substantially
                                the above form.)
 
                               METHOD OF DELIVERY
 
[ ] Check here if tendered Original Notes are enclosed herewith.
 
[ ] Check here if tendered Original Notes are being delivered by book-entry
    transfer made to an account maintained by the Exchange Agent with a
    Book-Entry Transfer Facility and complete the following:
 
    Name of Tendering Institution:
 
    Account Number:
 
    Transaction Code Number:
 
[ ] Check here if tendered Original Notes are being delivered pursuant to a
    Notice of Guaranteed Delivery and complete the following:
 
    Name(s) of Registered Holder(s):
 
    Date of Execution of Notice of Guaranteed Delivery:
 
    Window Ticket Number (if available):
 
    Name of Eligible Institution that guaranteed delivery:
 
    Account Number (If delivered by book-entry transfer):
 
                                       -3-
   4
 
                       SIGNATURES MUST BE PROVIDED BELOW
              PLEASE READ THE ACCOMPANYING INSTRUCTIONS CAREFULLY
 
Ladies and Gentlemen:
 
     1. The undersigned hereby tenders to the Company the Original Notes
described above pursuant to the Company's offer of $1,000 principal amount of
registered Exchange Notes, in exchange for each $1,000 principal amount of the
Original Notes, upon the terms and subject to the conditions contained in the
Prospectus, receipt of which is hereby acknowledged, and this Letter of
Transmittal.
 
     2. The undersigned hereby represents and warrants that it has full
authority to tender, exchange, assign and transfer the Original Notes described
above. The undersigned will, upon request, execute and deliver any additional
documents deemed by the Exchange Agent or the Company to be necessary or
desirable to complete the exchange, assignment and transfer of Original Notes.
 
     3. The undersigned understands that the tender of the Original Notes
pursuant to all of the procedures set forth in the Prospectus will constitute an
agreement between the undersigned and the Company as to the terms and conditions
set forth in the Prospectus.
 
     4. The undersigned acknowledge(s) that this Exchange Offer is being made in
reliance upon interpretations contained in no-action letters issued to third
parties by the staff of the Securities and Exchange Commission (the "SEC"),
including Exxon Capital Holdings Corporation, SEC No-Action (available April 13,
1989), Morgan Stanley & Co. Inc., SEC No-Action Letter (available June 5, 1991)
(the "Morgan Stanley Letter") and Mary Kay Cosmetics, Inc., SEC No-Action Letter
(available June 5, 1991), that the Exchange Notes issued in exchange for the
Original Notes pursuant to the Exchange Offer may be offered for resale, resold
and otherwise transferred by holders thereof (other than a broker-dealer who
purchased Original Notes exchanged for such Exchange Notes directly from the
Company to resell pursuant to Rule 144A or any other available exemption under
the Securities Act and any such holder that is an "affiliate" of the Company
within the meaning of Rule 405 under the Securities Act), without compliance
with the registration and prospectus delivery provisions of the Securities Act,
provided that such Exchange Notes are acquired in the ordinary course of such
holders' business and such holders are not participating in, and have no
arrangement with any person to participate in, the distribution of such Exchange
Notes.
 
     5. Unless the box under the heading "Special Registration Instructions" is
checked, the undersigned hereby represents and warrants that:
 
          (i) the Exchange Notes acquired pursuant to the Exchange Offer are
     being obtained in the ordinary course of business of the holder;
 
          (ii) the holder is not engaging in and does not intend to engage in a
     distribution of such Exchange Notes;
 
          (iii) the holder does not have an arrangement or understanding with
     any person to participate in the distribution of such Exchange Notes; and
 
          (iv) the holder is not an "affiliate," as such term is defined under
     Rule 405 promulgated under the Securities Act, of the Company.
 
     6. The undersigned may, if, and only if, unable to make all of the
representations and warranties contained in Item 5 above, elect to have its
Original Notes registered in the shelf registration statement described in the
registration rights agreement (the "Registration Rights Agreement") dated as of
May 21, 1998 among the Company, the Guarantors and the Initial Purchasers. Such
election may be made by checking the box under "Special Registration
Instructions" on page 7. By making such election, the undersigned agrees, as a
holder of Transfer Restricted Securities participating in a shelf registration,
to indemnify and hold harmless the Company, each of the Guarantors and each
person, if any, who controls the Company or any of the Guarantors within the
meaning of either Section 15 of the Securities Act or Section 20 of the
Securities Exchange Act of 1934, as amended (the "Exchange Act"), and each of
their respective
 
                                       -4-
   5
 
officers, directors, employees, partners, representatives and agents from and
against any and all losses, liabilities, claims, damages and expenses whatsoever
(including but not limited to reasonable attorneys' fees and any and all
reasonable expenses whatsoever incurred in investigating, preparing or defending
against any investigation or litigation, commenced or threatened, or any claim
whatsoever, and any and all amounts paid in settlement of any claim or
litigation), joint or several, to which they or any of them may become subject
under the Securities Act, the Exchange Act or otherwise, insofar as such losses,
liabilities, claims, damages or expenses (or actions in respect thereof) arise
out of or are based upon any untrue statement or alleged untrue statement of a
material fact contained in any Registration Statement or Prospectus, or in any
supplement thereto or amendment thereof, or arise out of or are based upon the
omission or alleged omission to state therein a material fact required to be
stated therein or necessary to make the statements therein, in the light of the
circumstances under which they were made, not misleading; but only with respect
to information relating to the undersigned furnished in writing by or on behalf
of the undersigned expressly for use in the Registration Statement, the
Prospectus or any amendments or supplements thereto. Any such indemnification
shall be governed by the terms and subject to the conditions set forth in the
Registration Rights Agreement, including, without limitation, the provisions
regarding notice, retention of counsel, contribution and payment of expenses set
forth therein. The above summary of the indemnification provision of the
Registration Rights Agreement is not intended to be exhaustive and is qualified
in its entirety by the Registration Rights Agreement.
 
     7. If the undersigned is not a broker-dealer, the undersigned represents
that it is not engaged in, and does not intend to engage in, a distribution of
Exchange Notes. If the undersigned is a broker-dealer that will receive Exchange
Notes for its own account in exchange for Original Notes that were acquired as a
result of market-making activities or other trading activities, it acknowledges
that it will deliver a prospectus in connection with any resale of such Exchange
Notes; however, by so acknowledging and delivering a prospectus, the undersigned
will not be deemed to admit that it is an "underwriter" within the meaning of
the Securities Act. If the undersigned is a broker-dealer and Original Notes
held for its own account were not acquired as a result of market-making or other
trading activities, such Original Notes cannot be exchanged pursuant to the
Exchange Offer.
 
     8. Any obligation of the undersigned hereunder shall be binding upon the
successors, assigns, executors, administrators, trustees in bankruptcy and legal
and personal representatives of the undersigned.
 
     9. Unless otherwise indicated herein under "Special Delivery Instructions,"
please issue the certificates for the Exchange Notes in the name of the
undersigned.
 
                                       -5-
   6
 
                         SPECIAL ISSUANCE INSTRUCTIONS
                           (SEE INSTRUCTIONS 5 AND 6)
 
To be completed only (i) if Original Notes in a principal amount not tendered,
or Exchange Notes issued in exchange for Original Notes accepted for exchange,
are to be issued in the name of someone other than the undersigned, or (ii) if
Original Notes tendered by book-entry transfer which are not exchanged are to be
returned by credit to an account maintained at the Book-Entry Transfer Facility.
Issue Exchange Notes and/or Original Notes to:
 
Name
- ----------------------------------------
                                (Type or Print)
 
Address
- --------------------------------------
 
- ------------------------------------------------
                                   (Zip Code)
 
- ------------------------------------------------
                 (Tax Identification or Social Security Number)
                         (Complete Substitute Form W-9)
 
                       Credit Unexchanged Original Notes
                        Delivered by Book-Entry Transfer
                      to the Book-Entry Transfer Facility
                                Set Forth Below:
 
- ------------------------------------------------
 
                          Book-Entry Transfer Facility
                                Account Number:
 
- ------------------------------------------------
 
- ------------------------------------------------
 
                         SPECIAL DELIVERY INSTRUCTIONS
                           (SEE INSTRUCTIONS 5 AND 6)
 
     To be completed ONLY if the Exchange Notes are to be issued or sent to
someone other than the undersigned or to the undersigned at an address other
than as indicated above.
 
Mail [ ] Issue [ ] (check appropriate boxes)
Certificates to:
 
Name
- ----------------------------------------
                                (Type or Print)
 
Address
- --------------------------------------
 
- ------------------------------------------------
                                   (Zip Code)
 
- ------------------------------------------------
                 (Tax Identification or Social Security Number)
 
- ------------------------------------------------
 
                                       -6-
   7
 
                       SPECIAL REGISTRATION INSTRUCTIONS
 
     To be completed ONLY if (i) the undersigned satisfies the conditions set
forth in Item 6 above, (ii) the undersigned elects to register its Original
Notes in the shelf registration statement described in the Registration Rights
Agreement and (iii) the undersigned agrees to indemnify certain entities and
individuals as set forth in Item 6 above. (See Item 6)
 
[ ] By checking this box the undersigned hereby (i) represents that it is unable
    to make all of the representations and warranties set forth in Item 5 above,
    (ii) elects to have its Original Notes registered pursuant to the shelf
    registration statement described in the Registration Rights Agreement and
    (iii) agrees to indemnify certain entities and individuals identified in,
    and to the extent provided in, Item 6 above.
 
                       SPECIAL BROKER-DEALER INSTRUCTIONS
 
[ ] Check here if you are a broker-dealer and wish to receive 10 additional
    copies of the Prospectus and 10 copies of any amendments or supplements
    thereto.
 
Name
- --------------------------------------------------------------------------------
 
Address
- --------------------------------------------------------------------------------
 
(Zip Code)
- --------------------------------------------------------------------------------
 
                                   IMPORTANT
                        PLEASE SIGN HERE WHETHER OR NOT
              ORIGINAL NOTES ARE BEING PHYSICALLY TENDERED HEREBY
          (COMPLETE ACCOMPANYING SUBSTITUTE FORM W-9 ON REVERSE SIDE)
 
(Signature(s) of Registered Holders of Original Notes)
- ------------------------------------------------------
 
- --------------------------------------------------------------------------------
 
- --------------------------------------------------------------------------------
 
Dated             , 1998
 
     (The above lines must be signed by the registered holder(s) of Original
Notes as name(s) appear(s) on the Original Notes or on a security position
listing, or by person(s) authorized to become registered holder(s) by a properly
completed bond power from the registered holder(s), a copy of which must be
transmitted with this Letter of Transmittal. If Original Notes to which this
Letter of Transmittal relate are held of record by two or more joint holders,
then all such holders must sign this Letter of Transmittal. If signature is by a
trustee, executor, administrator, guardian, attorney-in-fact, officer of a
corporation or other person acting in a fiduciary or representative capacity,
then such person must (i) set forth his or her full title below and (ii) unless
waived by the Company, submit evidence satisfactory to the Company of such
person's authority so to act. See Instruction 5 regarding completion of this
Letter of Transmittal, printed below.)
 
Name(s)
- --------------------------------------------------------------------------------
                             (Please Type or Print)
 
Capacity:
- --------------------------------------------------------------------------------
 
Address:
- --------------------------------------------------------------------------------
                               (Include Zip Code)
 
Area Code and Telephone Number:
- ---------------------------------------------------------------------------
                                       -7-
   8
 
                         MEDALLION SIGNATURE GUARANTEE
                         (IF REQUIRED BY INSTRUCTION 5)
 
Certain signatures must be Guaranteed by an Eligible Institution.
 
Signature(s) Guaranteed by an Eligible Institution:
 
(Authorized Signature)
- --------------------------------------------------------------------------------
 
(Title)
- --------------------------------------------------------------------------------
 
(Name of Firm)
- --------------------------------------------------------------------------------
 
(Address, Include Zip Code)
 
(Area Code and Telephone Number)
- -------------------------------------------------------------------------
 
Dated:  ______________ , 1998
 
                                  INSTRUCTIONS
         FORMING PART OF THE TERMS AND CONDITIONS OF THE EXCHANGE OFFER
 
1. DELIVERY OF THIS LETTER OF TRANSMITTAL AND ORIGINAL NOTES OR BOOK-ENTRY
   CONFIRMATIONS.
 
     All physically delivered Original Notes or any confirmation of a book-entry
transfer to the Exchange Agent's account at the Book-Entry Transfer Facility of
Original Notes tendered by book-entry transfer (a "Book-Entry Confirmation"), as
well as a properly completed and duly executed copy of this Letter of
Transmittal or Agent's Message or facsimile hereof, and any other documents
required by this Letter of Transmittal, must be received by the Exchange Agent
at its address set forth herein prior to 5:00 p.m., New York City time, on the
Expiration Date. The method of delivery of the tendered Original Notes, this
Letter of Transmittal and all other required documents to the Exchange Agent is
at the election and risk of the holder and, except as otherwise provided below,
the delivery will be deemed made only when actually received or confirmed by the
Exchange Agent. If such delivery is by mail, it is recommended that registered
mail, properly insured, with return receipt requested, be used. Instead of
delivery by mail, it is recommended that the holder use an overnight or hand
delivery service. In all cases, sufficient time should be allowed to assure
delivery to the Exchange Agent before the Expiration Date. No Letter of
Transmittal or Original Notes should be sent to the Company.
 
2. GUARANTEED DELIVERY PROCEDURES.
 
     Holders who wish to tender their Original Notes and whose Original Notes
are not immediately available or who cannot deliver their Original Notes, this
Letter of Transmittal or any other documents required hereby to the Exchange
Agent prior to the Expiration Date or who cannot complete the procedure for
book-entry transfer on a timely basis and deliver an Agent's Message, must
tender their Original Notes according to the guaranteed delivery procedures set
forth in the Prospectus. Pursuant to such procedures a tender may be effected if
the Exchange Agent has received at its office, on or prior to the Expiration
Date, a letter, telegram or facsimile transmission from an Eligible Institution
setting forth the name and address of the tendering holder, the name(s) in which
the Original Notes are registered and the certificate number(s) of the Original
Notes to be tendered, and stating that the tender is being made thereby and
guaranteeing that, within three Nasdaq National Market trading days after the
date of execution of such letter, telegram or facsimile transmission by the
Eligible Institution, such Original Notes, in proper form for transfer (or a
confirmation of book-entry transfer of such Original Notes into the Exchange
Agent's account at DTC), will be delivered by such Eligible Institution together
with a properly completed and duly executed Letter of Transmittal (and any other
required documents). Unless Original Notes being tendered by the above-described
method are deposited with the Exchange Agent within the time period set forth
above (accompanied or preceded by a
                                       -8-
   9
 
properly completed Letter of Transmittal and any other required documents), the
Company may, at its option, reject the tender.
 
     Any holder of Original Notes who wishes to tender Original Notes pursuant
to the guaranteed delivery procedures described above must ensure that the
Exchange Agent receives the Notice of Guaranteed Delivery prior to 5:00 p.m.,
New York City time, on the Expiration Date. Upon request of the Exchange Agent,
a Notice of Guaranteed Delivery will be sent to holders who wish to tender their
Original Notes according to the guaranteed delivery procedures set forth above.
See "The Exchange Offer -- Terms of the Exchange Offer -- Guaranteed Delivery
Procedures" section of the Prospectus.
 
3. TENDER BY HOLDER.
 
     Only a holder of Original Notes may tender such Original Notes in the
Exchange Offer. Any beneficial holder of Original Notes who is not the
registered holder and who wishes to tender should arrange with the registered
holder to execute and deliver this Letter of Transmittal on his behalf or must,
prior to completing and executing this Letter of Transmittal and delivering his
Original Notes, either make appropriate arrangements to register ownership of
the Original Notes in such holder's name or obtain a properly completed bond
power from the registered holder.
 
4. PARTIAL TENDERS.
 
     Tenders of Original Notes will be accepted only in integral multiples of
$1,000. If less than the entire principal amount of any Original Notes is
tendered, the tendering holder should fill in the principal amount-tendered in
the third column of the box entitled "Description of Original Notes Tendered"
above. The entire principal amount of Original Notes delivered to the Exchange
Agent will be deemed to have been tendered unless otherwise indicated. If the
entire principal amount of all Original Notes is not tendered, then Original
Notes for the principal amount of Original Notes not tendered and Exchange Notes
issued in exchange for any Original Notes accepted will be sent to the holder at
his or her registered address, unless a different address is provided in the
appropriate box on this Letter of Transmittal, promptly after the Original Notes
are accepted for exchange.
 
5. SIGNATURES ON THIS LETTER OF TRANSMITTAL; BOND POWERS AND ENDORSEMENTS;
   GUARANTEE OF SIGNATURES.
 
     If this Letter of Transmittal (or facsimile hereof) is signed by the record
holder(s) of the Original Notes tendered hereby, the signature must correspond
with the name(s) as written on the face of the Original Notes without
alteration, enlargement or any change whatsoever. If this Letter of Transmittal
(or facsimile hereof) is signed by a participant in the Book-Entry Transfer
Facility, the signature must correspond with the name as it appears on the
security position listing as the holder of the Original Notes.
 
     If this Letter of Transmittal (or facsimile hereof) is signed by the
registered holder or holders of Original Notes listed and tendered hereby and
the Exchange Notes issued in exchange therefor are to be issued (or any
untendered principal amount of Original Notes is to be reissued) to the
registered holder, the said holder need not and should not endorse any tendered
Original Notes, nor provide a separate bond power. In any other case, such
holder must either properly endorse the Original Notes tendered or transmit a
properly completed separate bond power with this Letter of Transmittal, with the
signatures on the endorsement or bond power guaranteed by an Eligible
Institution.
 
     If this Letter of Transmittal (or facsimile hereof) is signed by a person
other than the registered holder or holders of any Original Notes listed, such
Original Notes must be endorsed or accompanied by appropriate bond powers, in
each case signed as the name of the registered holder or holders appears on the
Original Notes.
 
     If this Letter of Transmittal (or facsimile hereof) or any Original Notes
or bond powers are signed by trustees, executors, administrators, guardians,
attorneys-in-fact, officers of corporations or others acting in a fiduciary or
representative capacity, such persons should so indicate when signing, and,
unless waived by the
 
                                       -9-
   10
 
Company, evidence satisfactory to the Company of their authority to act must be
submitted with this Letter of Transmittal.
 
     Endorsements on Original Notes or signatures on bond powers required by
this Instruction 5 must be guaranteed by an Eligible Institution.
 
     No signature guarantee is required if (i) this Letter of Transmittal (or
facsimile hereof) is signed by the registered holder(s) of the Original Notes
tendered herein (or by a participant in the Book-Entry Transfer Facility whose
name appears on a security position listing as the owner of the tendered
Original Notes) and the Exchange Notes are to be issued directly to such
registered holder(s) (or, if signed by a participant in the Book-Entry Transfer
Facility, deposited to such participant's account at such Book-Entry Transfer
Facility) and neither the box entitled "Special Delivery Instructions" nor the
box entitled "Special Registration Instructions" has been completed, or (ii)
such Original Notes are tendered for the account of an Eligible Institution. In
all other cases, all signatures on this Letter of Transmittal (or facsimile
hereof) must be guaranteed by an Eligible Institution.
 
6. SPECIAL REGISTRATION AND DELIVERY INSTRUCTIONS.
 
     Tendering holders should indicate, in the applicable box or boxes, the name
and address (or account at the Book-Entry Transfer Facility) to which Exchange
Notes or substitute Original Notes for principal amounts not tendered or not
accepted for exchange are to be issued or sent, if different from the name and
address of the person signing this Letter of Transmittal. In the case of
issuance in a different name, the taxpayer identification or social security
number of the person named must also be indicated.
 
     Tax law requires that a holder of any Original Notes which are accepted for
exchange must provide the Company (as payor) with its- correct taxpayer
identification number ("TIN"), which, in the case of a holder who is an
individual is his or her social security number. If the Company is not provided
with the correct TIN, the holder may be subject to a $50 penalty imposed by
Internal Revenue Service. (If withholding results in an overpayment of taxes, a
refund may be obtained). Certain holders (including, among others, all
corporations and certain foreign individuals) are not subject to these backup
withholding and reporting requirements. See the enclosed "Guidelines for
Certification of Taxpayer Identification Number on Substitute Form W-9" for
additional instructions.
 
     To prevent backup withholding, each tendering holder must provide such
holder's correct TIN by completing the Substitute Form W-9 set forth herein,
certifying that the TIN provided is correct (or that such holder is awaiting a
TIN), and that (i) the holder has not been notified by the Internal Revenue
Service that such holder is subject to backup withholding as a result of failure
to report all interest or dividends or (ii) the Internal Revenue Service has
notified the holder that such holder is no longer subject to backup withholding.
If the Original Notes are registered in more than one name or are not in the
name of the actual owner, see the enclosed "Guidelines for Certification of
Taxpayer Identification Number of Substitute Form W-9" for information on which
TIN to report.
 
     The Company reserves the right in its sole discretion to take whatever
steps are necessary to comply with the Company's obligations regarding backup
withholding.
 
7. VALIDITY OF TENDERS.
 
     All questions as to the validity, form, eligibility (including time of
receipt), acceptance, and withdrawal of tendered Original Notes will be
determined by the Company, in its sole discretion, which determination will be
final and binding. The Company reserves the absolute right to reject any or all
tenders not in proper form or the acceptance for exchange of which may, in the
opinion of counsel for the Company, be unlawful. The Company also reserves the
absolute right to waive any of the conditions of the Exchange Offer or any
defect or irregularity in the tender of any Original Notes. The Company's
interpretation of the terms and conditions of the Exchange Offer (including the
instructions in the Letter of Transmittal) will be final and binding on all
parties. Unless waived, any defects or irregularities in connection with tenders
of Original Notes must be cured within such time as the Company shall determine.
Although the Company intends to notify holders of defects
 
                                      -10-
   11
 
or irregularities with respect to tenders of Original Notes, neither the
Company, the Exchange Agent, nor any other person shall be under any duty to
give notification of any defects or irregularities in tenders or incur any
liability for failure to give such notification. Tenders of Original Notes will
not be deemed to have been made until such defects or irregularities have been
cured or waived. Any Original Notes received by the Exchange Agent that are not
properly tendered and as to which the defects or irregularities have not been
cured or waived will be returned by the Exchange Agent to the tendering holders,
unless otherwise provided in the Letter of Transmittal, as soon as practicable
following the Expiration Date.
 
8. WAIVER OF CONDITIONS.
 
     The Company reserves the absolute right to waive, in whole or part, any of
the conditions to the Exchange Offer set forth in the Prospectus.
 
9. NO CONDITIONAL TENDER.
 
     No alternative, conditional, irregular or contingent tender of Original
Notes on transmittal of this Letter of Transmittal will be accepted.
 
10. MUTILATED, LOST, STOLEN OR DESTROYED ORIGINAL NOTES.
 
     Any holder whose Original Notes have been mutilated, lost, stolen or
destroyed should contact the Exchange Agent at the address indicated above for
further instructions.
 
11. REQUESTS FOR ASSISTANCE OR ADDITIONAL COPIES.
 
     Requests for assistance or for additional copies of the Prospectus or this
Letter of Transmittal may be directed to the Exchange Agent at the address or
telephone number set forth on the cover page of this Letter of Transmittal.
Holders may also contact their broker, dealer, commercial bank, trust company or
other nominee for assistance concerning the Exchange Offer.
 
12. WITHDRAWAL.
 
     Tenders may be withdrawn only pursuant to the limited withdrawal rights set
forth in the Prospectus under the caption "The Exchange Offer -- Withdrawal
Rights."
 
IMPORTANT: THIS LETTER OF TRANSMITTAL OR A MANUALLY SIGNED FACSIMILE HEREOF
(TOGETHER WITH THE ORIGINAL NOTES DELIVERED BY BOOK-ENTRY TRANSFER OR IN
ORIGINAL HARD COPY FORM) MUST BE RECEIVED BY THE EXCHANGE AGENT, OR THE NOTICE
OF GUARANTEED DELIVERY MUST BE RECEIVED BY THE EXCHANGE AGENT, PRIOR TO THE
EXPIRATION DATE.
 
                                      -11-
   12
 


                                                                       
- --------------------------------------------------------------------------------------------------------------------
                                                                              -------------------------------------
 SUBSTITUTE               PART 1 -- PLEASE PROVIDE YOUR TIN IN THE BOX AT            Social Security Number
 FORM W-9                 RIGHT AND CERTIFY BY SIGNING AND DATING BELOW.                       OR
                                                                              -------------------------------------
                                                                                 Employer Identification Number
                         ------------------------------------------------------------------------------------------
 Department of the        PART 2 -- Certification Under penalties of perjury, I certify that:
 Treasury --              (1) The number shown on this form is my correct Taxpayer Identification Number (or I am
 Internal Revenue             waiting for a number to be issued to me) and
 Service                  (2) I am not subject to backup withholding either because I have not been notified by the
 PAYER'S REQUEST FOR          Internal Revenue Service ("IRS") that I am subject to backup withholding as a result
 TAXPAYER IDENTIFICATION      of failure to report all interest or dividends, or the IRS has notified me that I am
 NUMBER (TIN)                 no longer subject to backup withholding.
                          Certificate Instructions -- You must cross out item (2) in Part 2 above if you have been
                          notified by the IRS that you are subject to backup withholding because of under reporting
                          interest or dividends on your tax return. However, if after being notified by the IRS that
                          you were subject to backup withholding you received another notification from the IRS
                          stating that you are no longer subject to backup withholding, do not cross out item (2).
                         ------------------------------------------------------------------------------------------
                          SIGNATURE ____________                                            PART 3 --
                          DATE  ____________, 1998                                      Awaiting TIN  [ ]
                                                                               Please complete the Certificate of
                                                                             Awaiting Taxpayer Identification Number
                                                                                             below.
- --------------------------------------------------------------------------------------------------------------------

 
NOTE: FAILURE TO COMPLETE AND RETURN THIS FORM MAY RESULT IN BACKUP WITHHOLDING
      OF 31% OF ANY PAYMENTS MADE TO YOU PURSUANT TO THE OFFER. PLEASE REVIEW
      THE ENCLOSED GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION
      NUMBER ON SUBSTITUTE FORM W-9 FOR ADDITIONAL DETAILS.
 
YOU MUST COMPLETE THE FOLLOWING CERTIFICATE IF YOU CHECKED THE BOX IN PART 3 OF
                            THE SUBSTITUTE FORM W-9
 
             CERTIFICATE OF AWAITING TAXPAYER IDENTIFICATION NUMBER
 
     I certify under penalties of perjury that a taxpayer identification number
has not been issued to me, and either (a) I have mailed or delivered an
application to receive a taxpayer identification number to the appropriate
Internal Revenue Service Center or Social Security Administration Office or (b)
I intend to mail or deliver an application in the near future. I understand that
if I do not provide a taxpayer identification number to the payor within 60
days, 31% of all reportable payments made to me thereafter will be withheld
until I provide a number.
 
Signature ____________________     Date  ______________ , 1998
 
                     CERTIFICATE FOR FOREIGN RECORD HOLDERS
 
     Under penalties of perjury, I certify that I am not a United States citizen
or resident (or I am signing for a foreign corporation, partnership, estate or
trust).
 
Signature ____________________     Date  ______________ , 1998
 
                                      -12-
   13
 
                            AMERICAN ECO CORPORATION
 
                               LETTER TO CLIENTS
                                      FOR
                           TENDER OF ALL OUTSTANDING
                     9 5/8% SERIES A SENIOR NOTES DUE 2008
                                IN EXCHANGE FOR
                     9 5/8% SERIES B SENIOR NOTES DUE 2008
 
     THE EXCHANGE OFFER WILL EXPIRE AT 5:00 P.M., NEW YORK CITY TIME, ON
            , 1998, UNLESS EXTENDED (THE "EXPIRATION DATE").
 
     NOTES TENDERED IN THE EXCHANGE OFFER MAY BE WITHDRAWN AT ANY TIME PRIOR TO
5:00 P.M., NEW YORK CITY TIME, ON THE EXPIRATION DATE UNLESS PREVIOUSLY ACCEPTED
FOR EXCHANGE.
 
To Our Clients:
 
     We are enclosing herewith a Prospectus, dated          1998, of American
Eco Corporation, an Ontario, Canada corporation (the "Company"), and a related
Letter of Transmittal, which together constitute the Company's offer (the
"Exchange Offer") to exchange its 9 5/8% Series B Senior Notes due 2008 (the
"Exchange Notes"), which have been registered under the Securities Act of 1933,
as amended (the "Securities Act"), for a like principal amount of its issued and
outstanding 9 5/8% Series A Senior Notes due 2008 (the "Original Notes"), upon
the terms and subject to the conditions set forth in the Exchange Offer.
 
     The Exchange Offer is not conditioned upon any minimum number of Original
Notes being tendered.
 
     We are the holder of record of Original Notes held by us for your own
account. A tender of such Original Notes can be made only by us as the record
holder and pursuant to your instructions. The Letter of Transmittal is furnished
to you for your information only and cannot be used by you to tender Original
Notes held by us for your account.
 
     We request instructions as to whether you wish to tender any or all of the
Original Notes held by us for your account pursuant to the terms and conditions
of the Exchange Offer. We also request that you confirm that we may on your
behalf make the representations and warranties contained in the Letter of
Transmittal.
 
                                            Very truly yours,
 
     PLEASE RETURN YOUR INSTRUCTIONS TO US IN THE ENCLOSED ENVELOPE WITHIN AMPLE
TIME TO PERMIT US TO SUBMIT A TENDER ON YOUR BEHALF PRIOR TO THE EXPIRATION
DATE.
 
                                      -13-
   14
 
                    INSTRUCTION TO REGISTERED HOLDER AND/OR
                        BOOK-ENTRY TRANSFER PARTICIPANT
 
To Registered Holder and/or Participant of the Book-Entry Transfer Facility:
 
     The undersigned hereby acknowledges receipt of the Prospectus dated
            , 1998 (the "Prospectus") of American Eco Corporation, an Ontario,
Canada corporation (the "Company"), and the accompanying Letter of Transmittal
(the "Letter of Transmittal"), that together constitute the Company's offer (the
"Exchange Offer") to exchange its 9 5/8% Series B Senior Notes due 2008 (the
"Exchange Notes"), for all of its outstanding 9 5/8% Series A Senior Notes due
2008 (the "Original Notes"). Capitalized terms used but not defined herein have
the meanings ascribed to them in the Prospectus.
 
     This will instruct you, the registered holder and/or book-entry transfer
facility participant, as to the action to be taken by you relating to the
Exchange Offer with respect to the Original Notes held by you for the account of
the undersigned.
 
     The aggregate face amount of the Original Notes held by you for the account
of the undersigned is (FILL IN AMOUNT):
 
            $          of the 9 5/8% Series A Senior Notes due 2008.
 
     With respect to the Exchange Offer, the undersigned hereby instructs you
(CHECK APPROPRIATE BOX):
 
[ ] To TENDER the following Original Notes held by you for the account of the
    undersigned (INSERT PRINCIPAL AMOUNT OF ORIGINAL NOTES TO BE TENDERED) (IF
    ANY):
 
[ ] NOT to TENDER any Original Notes held by you for the account of the
    undersigned.
 
     If the undersigned instructs you to tender the Original Notes held by you
for the account of the undersigned, it is understood that you are authorized to
make, on behalf of the undersigned (and the undersigned by its signature below,
hereby makes to you), the representations and warranties contained in the Letter
of Transmittal that are to be made with respect to the undersigned as a
beneficial owner, including but not limited to the representations, that (i) the
Exchange Notes acquired in exchange for Original Notes pursuant to the Exchange
Offer are being acquired in the ordinary course of business of the person
receiving such Exchange Notes, whether or not the undersigned, (ii) the
undersigned is not engaging in and does not intend to engage in a distribution
of the Exchange Notes, (iii) the undersigned does not have any arrangement or
understanding with any person to participate in the distribution of Exchange
Notes, and (iv) neither the undersigned nor any such other person is an
"affiliate" (within the meaning of Rule 405 under the Securities Act of 1933, as
amended) of the Company. If the undersigned is a broker-dealer that will receive
Exchange Notes for its own account in exchange for Original Notes, it
acknowledges that it will deliver a prospectus in connection with any resale of
such Exchange Notes.
 
                                   SIGN HERE
 
Name of beneficial owner(s):
- --------------------------------------------------------------------------------
                                  Signature(s)
 
Name(s):
- --------------------------------------------------------------------------------
 
        ------------------------------------------------------------------------
 
        ------------------------------------------------------------------------
                                 (Please Print)
 
Address:
- --------------------------------------------------------------------------------
 
Telephone number:
- --------------------------------------------------------------------------------
 
Taxpayer Identification or Social Security Number:
- ----------------------------------------------------------
 
Date:
- --------------------------------------------------------------------------------
 
                                      -14-
   15
 
                            AMERICAN ECO CORPORATION
                        LETTER TO REGISTERED HOLDERS AND
                     DEPOSITORY TRUST COMPANY PARTICIPANTS
                                      FOR
                           TENDER OF ALL OUTSTANDING
                     9 5/8% SERIES A SENIOR NOTES DUE 2008
                                IN EXCHANGE FOR
                     9 5/8% SERIES B SENIOR NOTES DUE 2008
 
      THE EXCHANGE OFFER WILL EXPIRE AT 5:00 P.M., NEW YORK CITY TIME, ON
                     , 1998, UNLESS EXTENDED (THE "EXPIRATION DATE").
 
     ORIGINAL NOTES TENDERED IN THE EXCHANGE OFFER MAY BE WITHDRAWN AT ANY TIME
PRIOR TO 5:00 P.M., NEW YORK CITY TIME, ON THE EXPIRATION DATE UNLESS PREVIOUSLY
ACCEPTED FOR EXCHANGE.
 
To Registered Holders and Depository Trust Company Participants:
 
     We are enclosing herewith the material listed below relating to the offer
by American Eco Corporation, an Ontario, Canada corporation (the "Company"), to
exchange its 9 5/8% Series B Senior Notes due 2008 (the "Exchange Notes"), which
have been registered under the Securities Act of 1933, as amended (the
"Securities Act"), for a like principal amount of its issued and outstanding
9 5/8% Series A Senior Notes due 2008 (the "Original Notes") upon the terms and
subject to the conditions set forth in the Company's Prospectus, dated
            , 1998, and the related Letter of Transmittal (which together
constitute the "Exchange Offer").
 
     Enclosed herewith are copies of the following documents:
 
          1. Prospectus dated             , 1998;
 
          2. Letter of Transmittal (together with accompanying Substitute Form
     W-9 Guidelines);
 
          3. Notice of Guaranteed Delivery;
 
          4. Letter which may be sent to your clients for whose account you hold
     Original Notes in your name or in the name of your nominee; and
 
          5. Letter which may be sent from your clients to you with such
     client's instruction with regard to the Exchange Offer.
 
     We urge you to contact your clients promptly. Please note that the Exchange
Offer will expire on the Expiration Date unless extended.
 
     The Exchange Offer is not conditioned upon any minimum number of Original
Notes being tendered.
 
     Pursuant to the Letter of Transmittal, each holder of Original Notes will
represent to the Company that (i) the Exchange Notes acquired in exchange for
Original Notes pursuant to the Exchange Offer are being acquired in the ordinary
course of business of the person receiving such Exchange Notes, whether or not
the undersigned, (ii) the undersigned is not engaging in and does not intend to
engage in a distribution of the Exchange Notes, (iii) the undersigned does not
have any arrangement or understanding with any person to participate in the
distribution of Exchange Notes, and (iv) neither the undersigned nor any such
other person is an "affiliate" (within the meaning of Rule 405 under the
Securities Act of 1933, as amended) of the Company. If the holder is a
broker-dealer that will receive Exchange Notes for its own account in exchange
for Original Notes, it acknowledges that it will deliver a prospectus in
connection with any resale of such Exchange Notes.
 
                                      -15-
   16
 
     The enclosed Letter to Clients contains an authorization by the beneficial
owners of the Original Notes for you to make the foregoing representations.
 
     The Company will not pay any fee or commission to any broker or dealer or
to any other persons (other than the Exchange Agent) in connection with the
solicitation of tenders of Original Notes pursuant to the Exchange Offer.
 
     Additional copies of the enclosed material may be obtained from the
undersigned.
 
                                            Very truly yours,
 
                                            AMERICAN ECO CORPORATION
 
                                      -16-