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                                                                    Exhibit 10.1





                               TREX COMPANY, INC.
                      1999 STOCK OPTION AND INCENTIVE PLAN

                           RESTRICTED STOCK AGREEMENT

         Trex Company, Inc., a Delaware corporation (the "Company"), hereby
grants shares of its common stock, $.01 par value (the "Stock"), to the Grantee
named below, subject to the vesting conditions set forth in the attachment.
Additional terms and conditions of the grant are set forth in this cover sheet,
in the attachment and in the Company's 1999 Stock Option and Incentive Plan (the
"Plan").

Grant Date:  _______ __, 200_

Name of Grantee:  ________________________________________

Number of Shares of Stock Covered by Grant:  _________________

Purchase Price per Share of Stock:  $.01

         By signing this cover sheet, you agree to all of the terms and
conditions described in the attached Agreement and in the Plan, a copy of which
is available from the Company upon request. You acknowledge that you have
carefully reviewed the Plan, and agree that the Plan will control in the event
any provision of this Agreement should appear to be inconsistent.

Grantee:      _____________________________________________________
                                  (Signature)

Company:      _____________________________________________________
                                  (Signature)


              Title: ______________________________________________



Attachment
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         This is not a stock certificate or a negotiable instrument.

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                               TREX COMPANY, INC.
                      1999 STOCK OPTION AND INCENTIVE PLAN

                           RESTRICTED STOCK AGREEMENT

Restricted Stock/      This grant is an award of Stock in the number of shares
Nontransferability     set forth on the cover sheet, at the purchase price set
                       forth on the cover sheet, and subject to the vesting
                       conditions described below (the "Restricted Stock"). You
                       agree to pay the purchase price for the Restricted Stock
                       concurrently with your execution of this agreement. To
                       the extent not yet vested, your Restricted Stock may not
                       be transferred, assigned, pledged or hypothecated,
                       whether by operation of law or otherwise, nor may the
                       Restricted Stock be made subject to execution, attachment
                       or similar process.

Issuance and Vesting   The Company will issue your Restricted Stock in your name
                       as of the Grant Date.

                       Your right to the Stock under this Restricted Stock grant
                       will vest as to one third (1/3) of the total number of
                       shares covered by this grant, as shown on the cover
                       sheet, on March __, 2005, March __, 2006, and March __,
                       2007; provided, that, you remain a Service Provider on
                       each such vesting date. The resulting aggregate number of
                       vested shares of Stock will be rounded to the nearest
                       whole number, and you may not vest in more than the
                       number of shares covered by this grant.

                       No additional shares of Stock will vest after you have
                       ceased to be a Service Provider for any reason.

Right of Repurchase    In the event that you cease to be a Service Provider for
for Unvested Stock     any reason, the Company shall have the right to purchase
                       all of the shares of Stock subject to this grant that
                       have not yet vested (the "Repurchase Right"). If the
                       Company fails to purchase such Stock within 90 days after
                       the effective date of your termination as a Service
                       Provider, the Company's right to purchase such Stock
                       shall terminate. The purchase price for any Stock
                       repurchased shall be the price that you paid for those
                       shares of Stock and shall be paid in immediately
                       available funds.

Escrow                 The certificates for the Restricted Stock shall be
                       deposited in escrow with the Secretary of the Company to
                       be held in accordance with the provisions of this
                       paragraph. Each deposited certificate shall be
                       accompanied by a duly executed Assignment Separate from
                       Certificate in the form attached hereto as Exhibit A. The
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                       deposited certificates shall remain in

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                       escrow until such time or times as the certificates are
                       to be released or otherwise surrendered for cancellation
                       as discussed below. Upon delivery of the certificates to
                       the Company, you shall be issued an instrument of deposit
                       acknowledging the number of shares of Stock delivered in
                       escrow to the Secretary of the Company.

                       All regular cash dividends on the Stock (or other
                       securities at the time held in escrow) shall be paid
                       directly to you and shall not be held in escrow. However,
                       in the event of any stock dividend, stock split,
                       recapitalization or other change affecting the Stock as a
                       class effected without receipt of consideration, or in
                       the event of a stock split, a stock dividend or a similar
                       change in the Stock, any new, substituted or additional
                       securities or other property which is by reason of such
                       transaction distributed with respect to the Stock shall
                       be immediately delivered to the Secretary of the Company
                       to be held in escrow hereunder, but only to the extent
                       the Stock is at the time subject to the escrow
                       requirements hereof.

                       The shares of Stock held in escrow hereunder shall be
                       subject to the following terms and conditions relating to
                       their release from escrow or their surrender to the
                       Company for repurchase and cancellation:

                       .  As your interest in the shares vests as described
                          above, the certificates for such vested shares shall
                          be released from escrow and delivered to you, at your
                          request.

                       .  Should the Company exercise its Repurchase Right with
                          respect to any unvested shares held at the time in
                          escrow hereunder, then the escrowed certificates for
                          such unvested shares shall, concurrently with the
                          payment by the Company of the purchase price for such
                          shares of Stock, be surrendered to the Company for
                          cancellation, and you shall have no further rights
                          with respect to such shares of Stock.

                       .  Should the Company elect not to exercise its
                          Repurchase Right with respect to any shares held at
                          the time in escrow hereunder, then the escrowed
                          certificates for such shares shall be surrendered to
                          you.

Withholding Taxes      You agree, as a condition of this grant, that you will
                       make acceptable arrangements to pay any withholding or
                       other taxes that may be due as a result of the vesting of
                       Stock acquired under this grant. In the event that the
                       Company determines that

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                       any federal, state, local or foreign tax or withholding
                       payment is required relating to the vesting of shares
                       arising from this grant, the Company shall have the right
                       to require such payments from you, or withhold such
                       amounts from other payments due to you from the Company
                       or any Affiliate.


Section 83(b)          Under Section 83 of the Internal Revenue Code of 1986, as
Election               amended (the "Code"), the difference between the purchase
                       price paid for the shares of Stock and their fair market
                       value on the date any forfeiture restrictions applicable
                       to such shares lapse will be reportable as ordinary
                       income at that time. For this purpose, "forfeiture
                       restrictions" include the Company's Repurchase Right as
                       to unvested Stock described above. You may elect to be
                       taxed at the time the shares are acquired rather than
                       when such shares cease to be subject to such forfeiture
                       restrictions by filing an election under Section 83(b) of
                       the Code with the Internal Revenue Service within thirty
                       (30) days after the Grant Date. You will have to make a
                       tax payment to the extent the purchase price is less than
                       the fair market value of the shares on the Grant Date. No
                       tax payment will have to be made to the extent the
                       purchase price is at least equal to the fair market value
                       of the shares on the Grant Date. The form for making this
                       election is attached as Exhibit B hereto. Failure to make
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                       this filing within the thirty (30) day period will result
                       in the recognition of ordinary income by you (in the
                       event the fair market value of the shares increases after
                       the date of purchase) as the forfeiture restrictions
                       lapse.

                       YOU ACKNOWLEDGE THAT IT IS YOUR SOLE RESPONSIBILITY, AND
                       NOT THE COMPANY'S, TO FILE A TIMELY ELECTION UNDER
                       SECTION 83(b), EVEN IF YOU REQUEST THE COMPANY OR ITS
                       REPRESENTATIVES TO MAKE THIS FILING ON YOUR BEHALF. YOU
                       ARE RELYING SOLELY ON YOUR OWN ADVISORS WITH RESPECT TO
                       THE DECISION AS TO WHETHER OR NOT TO FILE ANY 83(b)
                       ELECTION.

Retention Rights       This Agreement does not give you the right to be retained
                       by the Company in any capacity. The Company reserves the
                       right to terminate your service with the Company at any
                       time and for any reason.

Shareholder Rights     You shall have the right to vote the Restricted Stock
                       and, subject to the provisions of this Agreement, to
                       receive any dividends declared or paid on such stock. Any
                       distributions you receive as a result of any stock split,
                       stock dividend, combination of shares

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                       or other similar transaction shall be deemed to be a part
                       of the Restricted Stock and subject to the same
                       conditions and restrictions applicable thereto. The
                       Company may in its sole discretion require any dividends
                       paid on the Restricted Stock to be reinvested in shares
                       of Stock, which the Company may in its sole discretion
                       deem to be a part of the shares of Restricted Stock and
                       subject to the same conditions and restrictions
                       applicable thereto. Except as described in the Plan, no
                       adjustments are made for dividends or other rights if the
                       applicable record date occurs before your stock
                       certificate is issued.

Adjustments            In the event of a stock split, a stock dividend or a
                       similar change in the Stock, the number of shares covered
                       by this grant may be adjusted (and rounded down to the
                       nearest whole number) pursuant to the Plan. Your
                       Restricted Stock shall be subject to the terms of the
                       agreement of merger, liquidation or reorganization in the
                       event the Company is subject to such corporate activity.

Legends                All certificates representing the Stock issued in
                       connection with this grant shall, where applicable, have
                       endorsed thereon the following legend:

                         "THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT
                         TO CERTAIN RESTRICTIONS ON TRANSFER AND OPTIONS TO
                         PURCHASE SUCH SHARES SET FORTH IN AN AGREEMENT BETWEEN
                         THE COMPANY AND THE REGISTERED HOLDER, OR THE HOLDER'S
                         PREDECESSOR IN INTEREST. A COPY OF SUCH AGREEMENT IS ON
                         FILE AT THE PRINCIPAL OFFICE OF THE COMPANY AND WILL BE
                         FURNISHED UPON WRITTEN REQUEST TO THE SECRETARY OF THE
                         COMPANY BY THE HOLDER OF RECORD OF THE SHARES
                         REPRESENTED BY THIS CERTIFICATE."

Applicable Law         This Agreement will be interpreted and enforced under the
                       laws of the State of Delaware, other than any conflicts
                       or choice of law rule or principle that might otherwise
                       refer construction or interpretation of this Agreement to
                       the substantive law of another jurisdiction.

The Plan               The text of the Plan is incorporated in this Agreement by
                       reference. Certain capitalized terms used in this
                       Agreement are defined in the Plan, and have the meaning
                       set forth in the Plan.

                       This Agreement and the Plan constitute the entire
                       understanding

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                       between you and the Company regarding this grant of
                       Restricted Stock. Any prior agreements, commitments or
                       negotiations concerning this grant are superseded.

         By signing the cover sheet of this Agreement, you agree to all of the
terms and conditions described above and in the Plan.

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