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                                                                     EXHIBIT 4.3

                                 AMENDMENT NO. 2
                                     TO THE
                         NCI 401(k) PROFIT SHARING PLAN

         THIS AMENDMENT NO. 2, executed this 21st day of May, 2003, and
effective as set forth herein, by NCI Building Systems, Inc., having its
principal office in Houston, Texas (hereinafter referred to as the "Company").

                              W I T N E S S E T H:

         WHEREAS, the Company amended and restated the NCI 401(k) Profit Sharing
Plan (the "Plan") effective generally as of January 1, 2001 to, among other
things, incorporate various changes to the Internal Revenue Code of 1986, as
amended applicable to the Plan; and

         WHEREAS, the Company amended the Plan further generally effective as of
January 1, 2002 to, among other things, incorporate certain provisions of the
Economic Growth and Tax Relief Reconciliation Act of 2001 applicable to the
Plan; and

         WHEREAS, the Company desires to adopt this Amendment No. 2 effective as
set forth herein to clarify certain administrative provisions applicable to the
Plan and to incorporate changes to the form of the volume submitter document
pursuant to which the Plan is maintained;

         NOW, THEREFORE, in consideration of the premises and the covenants
herein contained, the Company hereby adopts the following Amendment No. 2 to the
Plan:

1.       The Preamble to the Plan is hereby amended, effective January 1, 2001,
to add a new paragraph following the second paragraph thereof to read as
follows:

         Any sample amendment adopted by the Sponsor prior to this amendment and
restatement for purposes of complying with EGTRRA shall continue in effect after
this amendment and restatement.

2.       Section 7.1 of the Plan hereby is amended, effective January 1, 2001,
by restating the definition of testing year set forth therein in its entirety to
read as follows:

         The "TESTING YEAR" means the Plan Year immediately preceding the Plan
Year for which the limitations on "deferral percentages" and "contribution
percentages" of Highly Compensated Employees are being determined.

3.       Section 7.12 of the Plan hereby is amended, effective January 1, 2001,
by restatement in its entirety to read as follows:

         The income or loss attributable to "excess contributions" that are
distributed pursuant to this Article shall be determined by multiplying the
income or loss for the preceding Plan Year attributable to the Employee's
Sub-Account to which the "excess contributions" were credited by a fraction, the
numerator of which is the "excess contributions" made to such Sub-Account on the
Employee's behalf for the preceding Plan Year and the denominator of which is
(a) the

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balance of the Sub-Account on the last day of the preceding Plan Year, (b)
reduced by the gain attributable to contributions to such Sub-Account for the
preceding Plan Year, and (c) increased by the loss attributable to contributions
to such Sub-Account for the preceding Plan Year.

4.       Section 12.1 of the Plan hereby is amended, effective January 1, 2001,
by adding a new sentence to the end of the first paragraph thereof to read as
follows:

         To the extent that such written guidelines comply with the requirements
of Code Section 72(p), but are inconsistent with the provisions of this Article,
such written guidelines shall be given effect.

5.       Section 15.5 of the Plan hereby is amended, effective January 1, 2002,
by adding a new sentence to the end thereof to read as follows:

         With respect to distributions under the Plan made in calendar years
beginning on or after January 1, 2002, the Plan will apply the minimum
distribution requirements of Code Section 401(a)(9) in accordance with the
regulations under Code Section 401(a)(9) that were proposed in January 2001,
notwithstanding any provision of the Plan to the contrary. This provision shall
continue in effect until the end of the last calendar year beginning before the
effective date of final regulations under Code Section 401(a)(9) or such other
date specified in guidance published by the Internal Revenue Service.

6.       Section 18.4 of the Plan hereby is amended, effective January 1, 2001,
by restating the first sentence thereof in its entirety to read as follows:

         Whenever a claim for benefits under the Plan filed by any person
(herein referred to as the "Claimant") is denied, whether in whole or in part,
the Sponsor shall transmit a written notice of such decision to the Claimant
within 90 days of the date the claim was filed or, if special circumstances
require an extension, within 180 days of such date, which notice shall be
written in a manner calculated to be understood by the Claimant and shall
contain (i) a statement of the specific reasons for the denial of the claim,
(ii) specific reference to pertinent Plan provisions on which the denial is
based, (iii) a description of any additional material or information necessary
for the Claimant to perfect the claim and an explanation of why such information
is necessary, (iv) a statement that the Claimant is entitled to receive, upon
request and free of charge, reasonable access to, and copies of, all documents,
records and other information relevant to the Claimant's claim, (v) a
description of the review procedures and in the event of an adverse review
decision, a statement describing any voluntary review procedures and the
Claimant's right to obtain copies of such procedures, and (vi) a statement that
there is no further administrative review following the initial review, and that
the Claimant has a right to bring a civil action under ERISA Section 502(a) if
the Sponsor's decision on review is adverse to the Claimant.

7.       Section 18.4 of the Plan hereby is amended, effective January 1, 2002,
by adding a new paragraph to the end thereof to read as follows:

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         Notwithstanding the foregoing, special procedures apply for processing
claims and reviewing prior claim determinations if a Claimant's claim for
benefits is contingent upon a determination as to whether a Participant is
Disabled under the Plan.

8.       Section 19.3 of the Plan hereby is amended, effective January 1, 2001,
by restating clause (ii) of paragraph (c) thereof in its entirety to read as
follows:

         (ii) the distribution the Participant receives is a "lump sum
distribution" as defined in Code Section 402(e)(4), without regard to clauses
(I), (II), (III), and (IV) of sub-paragraph (D)(i) thereof.

9.       Section 19.4 of the Plan hereby is amended, effective January 1, 2001,
by restating clause (i) of the second sentence thereof in its entirety to read
as follows:

         (i) the distribution would constitute a "lump sum distribution" as
defined in Code Section 402(e)(4), without regard to clauses (I), (II), (III),
or (IV) of sub-paragraph (D)(i) thereof,

         IN WITNESS WHEREOF, the Company, acting by and through its duly
authorized officers, has caused this Amendment No. 2 to be executed as of the
day and year first above written.

                                          NCI BUILDING SYSTEMS, INC.

                                          By: /s/ Donnie R. Humphries
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                                                 Donnie R. Humphries, Secretary

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