EXHIBIT 4.1

                              TREX COMPANY, INC.
                       
                       1999 EMPLOYEE STOCK PURCHASE PLAN
                                        
The following constitute the provisions of the 1999 Employee Stock Purchase Plan
of Trex Company, Inc.

1.   Purpose.  The purpose of the Plan is to provide employees of the Company
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     and its Designated Subsidiaries with an opportunity to purchase Common
     Stock of the Company.  It is the intention of the Company to have the Plan
     qualify as an "Employee Stock Purchase Plan" under Section 423 of the
     Internal Revenue Code of 1986, as amended.  The provisions of the Plan
     shall, accordingly, be construed so as to extend and limit participation in
     a manner consistent with the requirements of that section of the Code.

2.   Definitions.
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(a)  "Board" shall mean the Board of Directors of the Company.
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(b)  "Code" shall mean the Internal Revenue Code of 1986, as amended.
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(c)  "Common Stock" shall mean the Common Stock of the Company.
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(d)  "Company" shall mean Trex Company, Inc., a Delaware corporation and any
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     entity which is treated as a "disregarded entity" pursuant to Section 7701
     of the Code.

(e)  "Compensation" shall mean all regular gross earnings (including scheduled
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     overtime) and commissions, and shall not include payments for unscheduled
     overtime, incentive compensation, incentive payments, bonuses and other
     compensation.

(f)  "Continuous Status as an Employee" shall mean the absence of any
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     interruption or termination of service as an Employee.  Continuous Status
     as an Employee shall not be considered interrupted in the case of a leave
     of absence agreed to in writing by the Company, provided that such leave is
     for a period of not more than 90 days or reemployment upon the expiration
     of such leave is guaranteed by contract or statute.

(g)  "Contributions" shall mean all amounts credited to the account of a
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     participant pursuant to the Plan.

(h)  "Employee" shall mean any person, including an Officer, who is customarily
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     employed for at least twenty (20) hours per week and more than five (5)
     months in a calendar year by the Company.

(j)  "Exchange Act" shall mean the Securities Exchange Act of 1934, as amended.
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(k)  "Exercise Date" shall mean the last day of each Offering Period of the
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     Plan.

(l)  "Offering Date" shall mean the first business day of each Offering Period
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     of the Plan.

(m)  "Offering Period" shall mean a period of three (3) months commencing on the
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     first business day of January, April, July and October of each year.

(n)  "Officer" shall mean a person who is an officer of the Company within the
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     meaning of Section 16 of the Exchange Act and the rules and regulations
     promulgated thereunder.

(o)  "Plan" shall mean this Employee Stock Purchase Plan.
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(p)  "Subsidiary" shall mean any company or other trade or business that is a
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     subsidiary of the Company (determined in accordance with the principles of
     Sections 424(e) and (f) of the Code and the regulations thereunder),
     whether or not such entity now exists or is hereafter organized or acquired
     by the Company or a Subsidiary.

3.   Eligibility.
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(a)  Any person who has been an Employee for six months as of the Offering Date
     for a given Offering Period shall be eligible to participate in such
     Offering Period under the Plan, subject to the requirements of Section 5(a)
     and the limitations imposed by Section 423(b) of the Code.

(b)  Any provisions of the Plan to the contrary notwithstanding, no Employee
     shall be granted an option under the Plan (i) if, immediately after the
     grant, such Employee (or any other person whose stock would be attributed
     to such employee pursuant to Section 424(d) of the Code) would own stock
     and/or hold outstanding options to purchase stock possessing five percent
     (5%) or more of the total combined voting power or value of all classes of
     stock of the Company or of any Subsidiary of the Company, or (ii) if such
     option would permit his or her rights to purchase stock under all employee
     stock purchase plans (described in Section 423 of the Code) of the Company
     and its Subsidiaries to accrue at a rate which exceeds Twenty-Five Thousand
     Dollars ($25,000) of fair market value of such stock (determined at the
     time such option is granted) for each calendar year in which such option is
     outstanding at any time.

4.   Offering Periods.
     ---------------- 

(a)  The Plan shall be implemented by a series of Offering Periods of three (3)
     months duration, other than the first Offering Period, with new Offering
     Periods commencing on the first business day of January, April, July and
     October of each year (or at such other time or times as may be determined
     by the Board of Directors).  The first Offering Period shall commence on
     the date determined by the Board of Directors and end on the last business
     day of the calendar quarter in which such Offering Period commenced.  The
     Plan shall continue until terminated in accordance with Section 19 hereof.
     The Board of

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     Directors of the Company shall have the power to change the duration and/or
     the frequency of Offering Periods with respect to future offerings without
     shareholder approval if such change is announced at least fifteen (15) days
     prior to the scheduled beginning of the first Offering Period to be
     affected. Eligible employees may not participate in more than one Offering
     Period at a time.

5.   Participation.
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(a)  An eligible Employee may become a participant in the Plan by completing a
     subscription agreement on the form provided by the Company and filing it
     with the Company's payroll office at least fifteen (15) days prior to the
     applicable Offering Date, unless a later time for filing the subscription
     agreement is set by the Board for all eligible Employees with respect to a
     given offering.  The subscription agreement shall set forth the percentage
     of the participant's Compensation (which shall be not less than one percent
     (1%) and not more than fifteen percent (15%) to be paid as Contributions
     pursuant to the Plan.

(b)  Payroll deductions shall commence on the first payroll following the
     Offering Date and shall end on the last payroll paid on or prior to the
     Exercise Date of the Offering Period to which the subscription agreement is
     applicable, unless sooner terminated by the participant as provided in
     Section 10.

6.   Method of Payment of Contributions.
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(a)  The participant shall elect to have payroll deductions made on each payday
     during the Offering Period in an amount not less than one percent (1%) and
     not more than fifteen percent (15%) of such participant's Compensation on
     each such payday.  All payroll deductions made by a participant shall be
     credited to his or her account under the Plan.  A participant may not make
     any additional payments into such account.

(b)  A participant may discontinue his or her participation in the Plan as
     provided in Section 10, or, on one occasion only during the Offering
     Period, may decrease the rate of his or her Contributions during the
     Offering Period by completing and filing with the Company a new
     subscription agreement.  The change in rate shall be effective as of the
     beginning of the next calendar month following the date of filing of the
     new subscription agreement, if the agreement is filed at least ten (10)
     business days prior to such date and, if not, as of the beginning of the
     next succeeding calendar month.

(c)  Notwithstanding the foregoing, to the extent necessary to comply with
     Section 423(b)(8) of the Code and Section 3(b) herein, a participant's
     payroll deductions may be decreased to 0% at such time during any Offering
     Period which is scheduled to end during the current calendar year.  Payroll
     deductions shall recommence at the rate provided in such participant's
     subscription agreement at the beginning of the first Offering Period which
     is scheduled to end in the following calendar year, unless terminated by
     the participant as provided in Section 10.

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7.   Grant of Option.
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(a)  On the Offering Date of each Offering Period, each eligible Employee
     participating in such Offering Period shall be granted an option to
     purchase on the Exercise Date a number of shares of the Company's Common
     Stock determined by dividing such Employee's Contributions accumulated
     prior to such Purchase Date and retained in the participant's account as of
     the Exercise Date by the option price which is the lower of (i) eighty-five
     percent (85%) of the fair market value of a share of the Company's Common
     Stock on the Offering Date, or (ii) eighty-five percent (85%) of the fair
     market value of a share of the Company's Common Stock on the Exercise Date;
     provided, however, that the maximum number of shares and such purchase
     shall be subject to the limitations set forth in Sections 3(b) and 12.  The
     fair market value of a share of the Company's Common Stock shall be
     determined as provided in Section 7(b).

(b)  The option price per share of the shares offered in a given Offering Period
     shall be the lower of:  (i) eighty-five percent (85%) of the fair market
     value of a share of the Common Stock of the Company on the Offering Date;
     or (ii) eighty-five percent (85%) of the fair market value of a share of
     the Common Stock of the Company on the Exercise Date.  The fair market
     value of the Company's Common Stock on a given date shall be determined by
     the Board in its discretion as follows:  if shares of Common Stock are
     listed on an established national or regional stock exchange, are admitted
     to quotation on the National Association of Securities Dealers Automated
     Quotation System, or are publicly traded on an established securities
     market, the fair market value of the shares of Common Stock shall be the
     closing price of the shares of Common Stock on such exchange or in such
     market (the highest such closing price if there is more than one such
     exchange or market) (or if there is no such reported closing price, the
     fair market value shall be the mean between the highest bid and lowest
     asked prices or between the high and low sale prices on such trading day)
     or, if no sale of the shares of Common Stock is reported for such trading
     day, on the next preceding day on which any sale shall have been reported.
     If the shares of Common Stock are not listed on such an exchange, quoted on
     such System or traded on such a market, fair market value shall be
     determined by the Board in good faith.

8.   Exercise of Option.  Unless a participant withdraws from the Plan as
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     provided in Section 10, his or her option for the purchase of shares will
     be exercised automatically on the Exercise Date of the Offering Period, and
     the maximum number of full shares subject to the option will be purchased
     at the applicable option price with the accumulated Contributions in his or
     her account.  The shares purchased upon exercise of an option hereunder
     shall be deemed to be transferred to the participant on the Exercise Date.
     During his or her lifetime, a participant's option to purchase shares
     hereunder is exercisable only by him or her.

9.   Issuance of Share Certificates.  On the Exercise Date, a participant will
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     be credited with the number of shares of Common Stock purchased for the
     participant's account under the Plan during the Offering Period.  Shares
     purchased under the Plan will be held in the custody of an agent (the
     "Agent") appointed by the Board of Directors.  The Agent may

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     hold the shares purchased under the Plan in stock certificates in nominee
     names and may commingle shares held in its custody in a single account or
     stock certificate without identification as to individual participating
     employees. A participant may, at any time following the purchase of shares
     under the Plan, by written notice instruct the Agent to have all or part of
     such shares reissued in the participant's own name and have the stock
     certificate delivered to the participant. Any cash remaining to the credit
     of a participant's account under the Plan after a purchase by him or her of
     shares at the termination of each Offering Period which is insufficient to
     purchase a full share of Common Stock of the Company shall be carried over
     to the next Offering Period if the Employee continues to participate in the
     Plan, or if the Employee does not continue to participate, shall be
     returned to such participant. Any other monies left over in a participant's
     account after an Exercise Date shall be returned to the Employee.

10.  Voluntary Withdrawal; Termination of Employment.
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(a)  A participant may withdraw all but not less than all the Contributions
     credited to his or her account under the Plan at any time prior to the
     Exercise Date of the Offering Period by giving written notice to the
     Company.  All of the participant's Contributions credited to his or her
     account will be paid to him or her promptly after receipt of his or her
     notice of withdrawal and his or her option for the current period will be
     automatically terminated, and no further Contributions for the purchase of
     shares will be made during the Offering Period.

(b)  Upon termination of the participant's Continuous Status as an Employee
     prior to the Exercise Date of an Offering Period for any reason, including
     retirement or death, the Contributions credited to his or her account will
     be returned to him or her or, in the case of his or her death, to the
     person or persons entitled thereto under Section 14, and his or her option
     will be automatically terminated.

(c)  In the event an Employee fails to remain in Continuous Status as an
     Employee of the Company for at least twenty (20) hours per week during the
     Offering Period in which the employee is a participant, he or she will be
     deemed to have elected to withdraw from the Plan and the Contributions
     credited to his or her account will be returned to him or her and his or
     her option terminated.

(d)  A participant's withdrawal from an offering will not have any effect upon
     his or her eligibility to participate in a succeeding offering or in any
     similar plan which may hereafter be adopted by the Company.

11.  Interest.  No interest shall accrue on the Contributions of a participant
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     in the Plan.

12.  Stock.
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(a)  The maximum number of shares of the Company's Common Stock which shall be
     made available for sale under the Plan shall be 300,000 shares, subject to
     adjustment upon

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     changes in capitalization of the Company as provided in Section 18. If the
     total number of shares which would otherwise be subject to options granted
     pursuant to Section 7(a) on the Offering Date of an Offering Period exceeds
     the number of shares then available under the Plan (after deduction of all
     shares for which options have been exercised or are then outstanding), the
     Company shall make a pro rata allocation of the shares remaining available
     for option grant in as uniform a manner as shall be practicable and as it
     shall determine to be equitable. In such event, the Company shall give
     written notice of such reduction of the number of shares subject to the
     option to each Employee affected thereby and shall similarly reduce the
     rate of Contributions, if necessary.

(b)  The participant will have no interest or voting right in shares covered by
     his or her option until such option has been exercised.

13.  Administration.  The Board, or a committee named by the Board, shall
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     supervise and administer the Plan and shall have full power to adopt, amend
     and rescind any rules deemed desirable and appropriate for the
     administration of the Plan and not inconsistent with the Plan, to construe
     and interpret the Plan, and to make all other determinations necessary or
     advisable for the administration of the Plan.  The composition of the
     committee shall be in accordance with the requirements to obtain or retain
     any available exemption from the operation of Section 16(b) of the Exchange
     Act pursuant to Rule 16b-3 promulgated thereunder.

14.  Designation of Beneficiary.
     -------------------------- 

(a)  A participant may file a written designation of a beneficiary who is to
     receive any shares and cash, if any, from the participant's account under
     the Plan in the event of such participant's death subsequent to the end of
     an Offering Period but prior to delivery to him or her of such shares and
     cash.  In addition, a participant may file a written designation of a
     beneficiary who is to receive any cash from the participant's account under
     the Plan in the event of such participant's death prior to the Exercise
     Date of an Offering Period.  If a participant is married and the designated
     beneficiary is not the spouse, spousal consent shall be required for such
     designation to be effective.

(b)  Such designation of beneficiary may be changed by the participant (and his
     or her spouse, if any) at the time by written notice.  In the event of the
     death of a participant and in the absence of a beneficiary validly
     designated under the Plan who is living at the time of such participant's
     death, the Company shall deliver such shares and/or cash to the executor or
     administrator of the estate of the participant, or if no such executor or
     administrator has been appointed (to the knowledge of the Company), the
     Company, in its discretion, may deliver such shares and/or cash to the
     spouse or to any one or more dependents or relatives of the participant, or
     if no spouse, dependent or relative is known to the Company, then to such
     other person as the Company may designate.

15.  Transferability.  Neither Contributions credited to a participant's account
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     nor any rights with regard to the exercise of an option or to receive
     shares under the Plan may be

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     assigned, transferred, pledged or otherwise disposed of in any way (other
     than by will, the laws of descent and distribution, or as provided in
     Section 13) by the participant. Any such attempt at assignment, transfer,
     pledge or other disposition shall be without effect, except that the
     Company may treat such act as an election to withdraw funds in accordance
     with Section 10.

16.  Use of Funds.  All Contributions received or held by the Company under the
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     Plan may be used by the Company for any corporate purpose, and the Company
     shall not be obligated to segregate such Contributions.

17.  Reports.  Individual accounts will be maintained for each participant in
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     the Plan.  Statements of account will be given to participating Employees
     promptly following the Exercise Date, which statements will set forth the
     amounts of Contributions, the per share purchase price, the number of
     shares purchased and the remaining cash balance, if any.

18.  Adjustments Upon Changes in Capitalization; Corporate Transactions.
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(a)  Adjustment.  Subject to any required action by the shareholders of the
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     Company, the number of shares of Common Stock covered by each option under
     the Plan which has not yet been exercised and the number of shares of
     Common Stock which have been authorized for issuance under the Plan but
     have not yet been placed under option (collectively, the "Reserves"), as
     well as the price per share of Common Stock covered by each option under
     the Plan which has not yet been exercised, shall be proportionately
     adjusted for any increase or decrease in the number of issued shares of
     Common Stock resulting from a stock split, reverse stock split, stock
     dividend, combination or reclassification of the Common Stock, or any other
     increase or decrease in the number of shares of Common Stock effected
     without receipt of consideration by the Company; provided, however, that
     conversion of any convertible securities of the Company shall not be deemed
     to have been "effected without receipt of consideration." Such adjustment
     shall be made by the Board, whose determination in that respect shall be
     final, binding and conclusive.  Except as expressly provided herein, no
     issue by the Company of shares of stock of any class, or securities
     convertible into shares of stock of any class, shall affect, and no
     adjustment by reason thereof shall be made with respect to, the number or
     price of shares of Common Stock subject to an option.

(b)  Corporate Transactions.  In the event of the proposed dissolution or
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     liquidation of the Company, the Offering Period will terminate immediately
     prior to the consummation of such proposed action, unless otherwise
     provided by the Board.  In the event of a proposed sale of all or
     substantially all of the assets of the Company, the merger of the Company
     with or into another corporation in which the Corporation is not the
     surviving corporation or upon any transaction (including, without
     limitation, a merger or reorganization in which the Company is the
     surviving corporation) approved by the Board that results in any person or
     entity owning more than 80 percent of the combined voting power of all
     classes of stock of the Company, each option under the Plan shall be
     assumed or an equivalent option shall be substituted by such successor
     corporation or a parent or

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     subsidiary of such successor corporation, unless the Board determines, in
     the exercise of its sole discretion and in lieu of such assumption or
     substitution, to shorten the Offering Period then in progress by setting a
     new Exercise Date (the "New Exercise Date"). If the Board shortens the
     Offering Period then in progress in lieu of assumption or substitution in
     the event of a merger or sale of assets, the Board shall notify each
     participant in writing, at least ten (10) days prior to the New Exercise
     Date, that the Exercise Date for his or her option has been changed to the
     New Exercise Date and that his or her option will be exercised
     automatically on the New Exercise Date, unless prior to such date he or she
     has withdrawn from the Offering Period as provided in Section 10. For
     purposes of this Section 18(b), an option granted under the Plan shall be
     deemed to be assumed if, following the sale of assets or merger, the option
     confers the right to purchase, for each share of option stock subject to
     the option immediately prior to the sale of assets or merger, the
     consideration (whether stock, cash or other securities or property)
     received in the sale of assets, merger or other transaction by holders of
     Common Stock for each share of Common Stock held on the effective date of
     the transaction (and if such holders were offered a choice of
     consideration, the type of consideration chosen by the holders of a
     majority of the outstanding shares of Common Stock); provided, however,
     that if such consideration received in the sale of assets, merger or other
     transaction was not solely common stock of the successor corporation or its
     parent (as defined in Section 424(e) of the Code), the Board may, with the
     consent of the successor corporation and the participant, provide for the
     consideration to be received upon exercise of the option to be solely
     common stock of the successor corporation or its parent equal in fair
     market value to the per share consideration received by holders of Common
     Stock and the sale of assets or merger.

     The Board may, if it so determines in the exercise of its sole discretion,
     also make provision for adjusting the Reserves, as well as the price per
     share of Common Stock covered by each outstanding option, in the event that
     the Company effects one or more reorganizations, recapitalizations, rights
     offerings or other increases or reductions of shares of its outstanding
     Common Stock, and in the event of the Company being consolidated with or
     merged into any other corporation.

20.  Amendment or Termination.
     ------------------------ 

(a)  The Board may at any time terminate or amend the Plan.  Except as provided
     in Section 19, no such termination may affect options previously granted,
     nor may an amendment make any change in any option theretofore granted
     which adversely affects the rights of any participant.  In addition, to the
     extent necessary to comply with Rule 16b-3 under the Exchange Act, or under
     Section 423 of the Code (or any successor rule or provision or any
     applicable law or regulation), the Company shall obtain shareholder
     approval in such a manner and to such a degree as so required.

(b)  Without shareholder consent and without regard to whether any participant
     rights may be considered to have been adversely affected, the Board (or its
     committee) shall be entitled to change the Offering Periods and Purchase
     Periods, change the option price per share

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     provided that such option price shall not be less than the lesser of eighty
     five percent (85%) of the fair market value of the Common Stock (i) on the
     Offering Date or (ii) on the Exercise Date, limit the frequency and/or
     number of changes in the amount withheld during an Offering Period,
     establish the exchange ratio applicable to amounts withheld in a currency
     other than U.S. dollars, permit payroll withholding in excess of the amount
     designated by a participant in order to adjust for delays or mistakes in
     the Company's processing of properly completed withholding elections,
     establish reasonable waiting and adjustment periods and/or accounting and
     crediting procedures to ensure that amounts applied toward the purchase of
     Common Stock for each participant properly correspond with amounts withheld
     from the participant's Compensation, and establish such other limitations
     or procedures as the Board (or its committee) determines in its sole
     discretion advisable which are consistent with the Plan.

21.  Notices.  All notices or other communications by a participant to the
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     Company under or in connection with the Plan shall be deemed to have been
     duly given when received in the form specified by the Company at the
     location, or by the person, designated by the Company for the receipt
     thereof.

22.  Conditions Upon Issuance of Shares.  Shares shall not be issued with
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     respect to an option unless the exercise of such option and the issuance
     and delivery of such shares pursuant thereto shall comply with all
     applicable provisions of law, domestic or foreign, including, without
     limitation, the Securities Act of 1933, as amended, the Exchange Act, the
     rules and regulations promulgated thereunder, and the requirements of any
     stock exchange upon which the shares may then be listed, and shall be
     further subject to the approval of counsel for the Company with respect to
     such compliance.

     As a condition to the exercise of an option, the Company may require the
     person exercising such option to represent and warrant at the time of any
     such exercise that the shares are being purchased only for investment and
     without any present intention to sell or distribute such shares if, in the
     option of counsel for the Company, such a representation is required by any
     of the aforementioned applicable provisions of law.

23.  Term of Plan; Effective Date.  The Plan shall become effective upon the
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     earlier to occur of its adoption by the Board of Directors or its approval
     by the shareholders of the Company.  It shall continue in effect for a term
     of twenty (20) years unless sooner terminated under Section 20.

24.  Additional Restrictions of Rule 16b-3.  The terms and conditions of options
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     granted hereunder to, and the purchase of shares by, persons subject to
     Section 16 of the Exchange Act shall comply with the applicable provisions
     of Rule 16b-3.  This Plan shall be deemed to contain, and such options
     shall contain, and the shares issued upon exercise thereof shall be subject
     to, such additional conditions and restrictions as may be required by Rule
     16b-3 to qualify for the maximum exemption from Section 16 of the Exchange
     Act with respect to Plan transactions.

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