UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the Securities

Exchange Act of 1934

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Trex Company, Inc.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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Trex Company, Inc.

2500 Trex Way

Winchester, Virginia 22601

Notice of Annual Meeting of Stockholders

April 28, 2026

To our stockholders:

Notice is hereby given that the 2026 annual meeting of stockholders of Trex Company, Inc. will be held at Trex University, 331 Apple Valley Road, Winchester, Virginia, on Tuesday, April 28, 2026, at 9:00 a.m., local time, for the following purposes:

Only stockholders of record at the close of business on March 06, 2026 will be entitled to notice of and to vote at the annual meeting or any adjournment or postponement thereof.

All stockholders are cordially invited to attend this meeting.

We have elected to adopt the U.S. Securities and Exchange Commission rule that allows companies to furnish their proxy materials over the Internet. As a result, we are mailing a Notice Regarding the Availability of Proxy Materials (the “Notice of Availability”) to our stockholders instead of a paper copy of this Proxy Statement and our 2025 Annual Report. The Notice of Availability contains instructions on how to access and review those documents over the Internet. We believe that this process will allow us to provide our stockholders with the information they need in a timelier manner, while reducing the environmental impact and lowering the costs of printing and distributing our proxy materials. Stockholders who receive a Notice of Availability by mail and would like to receive a printed copy of our proxy materials should follow the instructions for requesting such materials included on the Notice of Availability.

Your vote is very important to us. Whether or not you plan to attend the meeting in person, your shares should be represented and voted. To vote, please complete and return your proxy card, or vote by telephone or via the Internet by following the instructions on your Notice of Availability. Returning a proxy card or otherwise submitting your proxy does not deprive you of your right to attend the annual meeting and vote in person.

By Order of the Board of Directors,

Amy M. Fernandez

Senior Vice President, Chief Legal Officer

Secretary and Chief Sustainability Officer

Dated: March 16, 2026

Table of Contents

Proxy Summary

This summary highlights information contained elsewhere in this Proxy Statement. This summary does not contain all of the information you should consider. Please read the entire Proxy Statement carefully before voting.

Board of Directors

The following table provides summary information about each director*.

* The above matrix and charts do not include Mr. Bryan Fairbanks or Mr. Ron Kaplan who are retiring from the Board of

Directors effective the Annual Meeting on April 28, 2026.

**Chairman of the Board

*** Lead Independent Director

Experience/Qualifications/Skills/Attributes*

Director Tenure* Age Distribution*

Independence*

*The above matrix and charts do not include Mr. Bryan Fairbanks or Mr. Ron Kaplan who are retiring from the Board of Directors effective the Annual Meeting on April 28, 2026.

We believe that our directors should have a wide range of qualifications, including demonstrated integrity, a record of personal accomplishments, a commitment to participation in board activities, and other attributes discussed below in the “Director Nomination Policy” section on page 26. We endeavor to have a board that represents a range of qualifications, skills, and depth of experience in areas relevant to the Board’s oversight of the Company’s activities. Some of which we currently consider to be important are summarized below:

*The above matrix does not include Mr. Bryan Fairbanks or Mr. Ron Kaplan, who are retiring from the Board effective the Annual Meeting on April 28, 2026.

Trex Company, Inc.

2500 Trex Way

Winchester, Virginia 22601

Annual Meeting of Stockholders

April 28, 2026

Proxy Statement

General Information

This Proxy Statement is furnished in connection with the solicitation of proxies by the Board of Directors (the “Board”) of Trex Company, Inc. (the “Company”, “we” or “our”) for use at the Company’s 2026 annual meeting of stockholders to be held at Trex University, 331 Apple Valley Road, Winchester, Virginia, on Tuesday, April 28, 2026 at 9:00 a.m., local time. The purpose of the annual meeting and the matters to be acted upon are set forth in the accompanying notice of annual meeting.

Only stockholders of record at the close of business on March 06, 2026, the record date for the annual meeting (the “record date”), will be entitled to notice of and to vote at the annual meeting. As of March 06, 2026, we had 103,889,031 shares of common stock outstanding, which are our only securities entitled to vote at the annual meeting. Each share of common stock is entitled to one vote.

A complete list of stockholders entitled to vote at the annual meeting will be open to the examination of any stockholder, for any purpose germane to the meeting, during ordinary business hours for a period of ten days ending on the day before the meeting, at the Company’s offices at 2500 Trex Way, Winchester, Virginia.

Notice of the Company’s annual meeting was mailed on or about March 16, 2026 to all stockholders as of the record date.

Those stockholders entitled to vote may vote their shares via the Proxy Card, or via the Internet, telephone, or mail, following the instructions printed on the Notice of Availability.

Stockholders who receive a Notice of Availability and would like to receive a printed copy of our proxy materials should follow the instructions for requesting such materials included in the Notice of Availability.

From the date of the mailing of the Notice of Availability until the conclusion of the annual meeting, all of the proxy materials will be accessible on the Company’s website at www.trex.com/proxy.

Stockholders who execute proxies may revoke them by giving written notice to our Secretary any time before such proxies are voted. Attendance at the annual meeting shall not have the effect of revoking a proxy unless the stockholder so attending shall, in writing, so notify the Secretary at any time prior to the voting of the proxy at the annual meeting.

The Board does not know of any matter that is expected to be presented for consideration at the annual meeting, other than the election of four directors, a non-binding advisory vote on the compensation of our named executive officers, and ratification of the appointment of our independent registered public accounting firm for the current fiscal year. However, if other matters properly come before the annual meeting, the persons named in the accompanying proxy intend to vote thereon in accordance with their judgment.

We are not engaging any company for the purpose of proxy solicitation in conjunction with this Proxy Statement. We will bear the cost of the annual meeting and the cost of soliciting proxies, including the cost of mailing any proxy materials. In addition to solicitation by mail, our directors, officers, and regular employees (who will not be specifically compensated for such services) may solicit proxies by telephone or otherwise. Arrangements will be made with brokerage houses and other custodians, nominees, and fiduciaries to forward proxies and proxy material to their principals, and we will reimburse them for their expenses. In addition, we have retained Broadridge Financial Solutions, Inc., or Broadridge, to assist in the mailing, collection, and administration of the proxy.

The 2025 Annual Report to stockholders and the 2025 Form 10-K are not proxy soliciting materials.

All proxies received pursuant to this solicitation will be voted except as to matters where authority to vote is specifically withheld. Where a choice is specified as to the proposal, proxies will be voted in accordance with such specification. If no instructions are given, the persons named in the proxy intend to vote:

A majority of the outstanding shares of common stock entitled to vote on the record date, whether present in person or represented by proxy, will constitute a quorum for the transaction of business at the annual meeting and any adjournment or postponement thereof. Abstentions and broker non-votes (which occur with respect to any proposal when a broker holds shares of a customer in its name and is not permitted to vote on that proposal without instruction from the beneficial owner of the shares and no instruction is given) will be counted as present or represented for purposes of establishing a quorum for the transaction of business.

The following vote shall be required for approval of each matter:

Security Ownership

The following table presents, as of March 06, 2026, information based upon the Company’s records and filings with the U.S. Securities and Exchange Commission (“SEC”) regarding beneficial ownership of its common stock by the following persons:

As of March 06, 2026, there were 103,889,031 shares of common stock outstanding.

The following information has been presented in accordance with SEC rules and is not necessarily indicative of beneficial ownership for any other purpose. Under SEC rules, beneficial ownership of a class of capital stock as of any date includes any shares of such class as to which a person, directly or indirectly, has or shares voting power or investment power as of such date and also any shares as to which a person has the right to acquire such voting or investment power as of or within 60 days after such date through the exercise of any stock option, stock appreciation right, warrant or other right, without regard to whether such right expires before the end of such 60-day period or continues thereafter. If two or more persons share voting power or investment power with respect to specific securities, all such persons may be deemed to be the beneficial owners of such securities.

* Less than 1%.

Election of Directors

(Proposal 1)

The Company’s Restated Certificate of Incorporation, as amended, provides that the Board is to be divided into three classes of directors, with the classes to be as nearly equal in number as possible. The current terms of office of the three current classes of directors expire at this annual meeting, at the annual meeting of stockholders in 2027, and at the annual meeting of stockholders in 2028, respectively. Upon the expiration of the term of office of each class, the nominees for such class will be elected for a term of three years to succeed the directors whose terms of office expire.

In accordance with the recommendation of the Nominating/Corporate Governance Committee, Mr. Gratz, Mr. Rose, Ms. Tasi, and Mr. Volas have been nominated by the Board for election to the class with a three-year term that will expire at the annual meeting of stockholders in 2029. These nominees are incumbent directors.

Approval of the nominees requires the affirmative vote of a majority of the votes cast in favor of such nominee at the annual meeting. The term “Majority” for purposes of election of directors means that a nominee receives more votes in favor of such nominee than are cast against such nominee by the holders of shares present in person or represented by proxy and entitled to vote at the Annual Meeting. Abstentions and broker non-votes will have no effect on the election of directors. Brokers may vote their shares in favor of or against directors if they have voting instructions from the beneficial owners of the shares. Unless authority to do so is withheld, it is the intention of the persons named in the proxy to vote such proxy FOR the election of each of the nominees. If any of the nominees should become unable or unwilling to serve as a director, the persons named in the proxy intend to vote for the election of such substitute nominee for director as the Board may recommend. It is not anticipated that any of the nominees will be unable or unwilling to serve as a director.

The Board unanimously recommends that the stockholders of the Company vote FOR the election of the nominees to serve as directors.

Biographical information concerning each of the nominees and each of the directors continuing in office is presented below.

Corporate Governance

The Board currently consists of eleven directors. Mr. Ronald Kaplan is retiring effective April 28, 2026, at which time the Board will consist of ten directors.

The Board has three standing committees: the Audit Committee, the Compensation Committee, and the Nominating/Corporate Governance Committee. During the Company’s 2025 fiscal year, the Board held five meetings, the Audit Committee held five meetings, the Compensation Committee held five meetings, and the Nominating/Corporate Governance Committee held five meetings. During 2025, each director attended at least 75% of the aggregate of the total number of meetings of the Board and of each committee of the Board on which such director served. Mr. Rose who was appointed to the Board in December 2025 and Ms. Tasi who was appointed to the Board in February 2026 attended all meetings of the Board and of each committee of the Board on which they served which were held after their appointment.

It is the Company’s policy that all directors should attend annual meetings of the Company’s stockholders. All then-serving directors attended the annual meeting in May 2025.

The Board does not have a strict retirement age for directors. However, the Board does believe that once a director attains a certain age, the Board should carefully consider whether such director’s continued service on the Board is in the best interests of the Company. The Company’s Corporate Governance Principles provide that any director who will be age 75 or older by the next annual meeting of shareholders shall tender his or her resignation to the Board prior to the October meeting of the Board that precedes such annual meeting of shareholders, at which time the Board may elect to either accept such resignation or request that such director continue to serve on the Board.

Board Leadership Structure. Our Board is currently led by a non-executive Chairman, Mr. Cline, who retired as the Company’s President and Chief Executive Officer on April 28, 2020. Our Board determined that retaining Mr. Cline as Chairman was in the best interests of the Company because it allows the Company to benefit from Mr. Cline’s significant experience and accumulated expertise in the Company’s industry and the Company’s internal policies, practices, and procedures to effectively and expertly guide the Board. Mr. Cline’s familiarity with the Company’s executives reinforces that the Board and executives will operate with continuity and common purpose. The Board determined that having Mr. Cline as Chairman allows the Company’s President and Chief Executive Officer to focus on executing the Company’s strategy and managing operations and performance. The Board is further comprised of a Lead Independent Director, an independent Audit Committee Chairman, an independent Compensation Committee Chairman, and an independent Nominating/Corporate Governance Committee Chairwoman. These independent positions align with the Company’s corporate governance policies and practices and assure adequate independence of the Board.

Since July 25, 2023, Ms. Robinson has served as Lead Independent Director. Ms. Robinson is an experienced former chief executive officer. (For additional information regarding Ms. Robinson’s professional experience, please see “Election of Directors (Proposal 1).” Pursuant to the Company’s Corporate Governance Principles, the responsibilities of the Lead Independent Director include: presiding at executive sessions of the independent directors; presiding at Board meetings in the absence of the Chairman; making recommendations and consulting with management with regard to Board meeting agendas, materials, and schedules; and serving as a liaison between the independent directors and members of senior management.

Director Independence. The Board has affirmatively determined that all of the current directors, other than Mr. Fairbanks, who is the Company’s current President and Chief Executive Officer, are “independent” of the Company within the independence guidelines governing companies listed on the New York Stock Exchange (“NYSE”). For a director to be “independent” under the NYSE guidelines, the Board must affirmatively determine that the director has no material relationship with the Company, either directly or as a partner, stockholder, or officer of an organization that has a relationship with the Company.

The Board has adopted the following categorical standards of independence to assist it in determining whether a director has a material relationship with the Company. The following relationships between a director and the Company will not be considered material relationships that would preclude a finding by the Board that the director is independent under the NYSE guidelines:

Furthermore, the Board has also determined, consistent with NYSE guidelines, a director is not independent if:

Consistent with the NYSE guidelines, the Company’s corporate governance principles require the Company’s non-management directors to meet at least once each quarter without management present and, if the group of non-management directors includes any director who is not independent under NYSE guidelines, to meet at least once each year with only the independent directors present. The Company’s non-management directors, all of whom are independent under NYSE guidelines, held five executive sessions in 2025.

Our Board has three standing committees:

Each of these committees plays an important role in the governance and leadership of our Board and each is chaired by an independent director with significant business experience.

Audit Committee. During 2025, the Audit Committee of the Board was composed of four non-employee directors from January 1, 2025 through October 31, 2025, three non-employee directors from November 1, 2025 until December 3, 2025, and four non-employee directors since December 3, 2025, all of whom meet the independence and expertise requirements of the NYSE listing standards: Mr. Volas who is currently Chairman, Mr. Gratz, Ms. Lovett, Ms. McDuffie from January 1, 2025 through October 31, 2025, and Mr. Rose since December 3, 2025. Pursuant to SEC rules, the Board has determined that Mr. Volas, Mr. Gratz, and Mr. Rose are “audit committee financial experts,” as such term is defined for purposes of Item 407 of Regulation S-K promulgated by the SEC, and are independent of management. The Audit Committee held five meetings during 2025.

The Audit Committee operates under a written charter that is reviewed annually. The Audit Committee is responsible, among its other duties, for engaging, overseeing, evaluating, and replacing the Company’s independent registered public accounting firm, pre-approving all audit and non-audit services by the independent registered public accounting firm, reviewing the scope of the audit plan and the results of each audit with management and the independent registered public accounting firm, reviewing the internal audit function, reviewing the adequacy of the Company’s system of internal controls over financial reporting and disclosure controls and procedures, reviewing the financial statements and other financial information included in the Company’s annual and quarterly reports filed with the SEC, reviewing the efficacy of the Company’s information security and technology risks (including cybersecurity) and related policies and procedures, which include receiving quarterly reports from the Company’s Executive Information Security Oversight Committee by our Vice President, Chief Information Officer, who is tasked with monitoring cybersecurity risks, and exercising oversight with respect to the Company’s Code of Conduct and Ethics and other policies and procedures regarding adherence with legal requirements. The Audit Committee has the authority to retain and terminate any third-party consultants and to obtain advice and assistance from internal and external legal, accounting, and other advisers. The Audit Committee is authorized to delegate its authority to subcommittees as determined to be necessary or advisable. A current version of the Audit Committee charter is available on the Company’s website at www.trex.com/our-company/corporate-governance/committees-charters/.

Compensation Committee. During 2025, the Compensation Committee of the Board was composed of five non-employee directors from January 1, 2025 through October 31, 2025, four non-employee directors from November 1, 2025 until December 3, 2025, and five non-employee directors since December 3, 2025, who meet the independence requirements of the NYSE listing standards: Mr. Gratz, who is Chairman, Ms. Juster, Mr. Keffer, Ms. Robinson, Ms. McDuffie from January 1, 2025 through October 31, 2025, and Mr. Rose since December 3, 2025. The Compensation Committee held five meetings during 2025.

The Compensation Committee operates under a written charter that is reviewed annually. Pursuant to its charter, the principal functions of the Compensation Committee are to review, determine, and approve the compensation and benefits of the Company’s President and Chief Executive Officer (“CEO”) and the other executive officers named in the Summary Compensation Table following the Compensation Discussion and Analysis section of this Proxy Statement, or “named executive officers,” as well as other executive officers, and to administer the Company’s employee benefit programs, including its Amended and Restated 2023 Stock Incentive Plan (the “2023 Stock Incentive Plan”), which amended and restated the 2014 Stock Incentive Plan (the “2014 Stock Incentive Plan”), Amended and Restated 1999 Employee Stock Purchase Plan (“1999 Employee Stock Purchase Plan”), annual cash incentive plan, and other incentive compensation plans, benefit plans and equity-based plans.

The Compensation Committee has the authority to retain and terminate any third-party compensation consultant and to obtain advice and assistance from internal and external legal, accounting, and other advisers. (See the Compensation Discussion and Analysis section of this Proxy Statement for information regarding the practices of the Compensation Committee, including the role of the officers and the Compensation Committee’s compensation consultant in determining or recommending the amount and form of compensation paid to the named executive officers.) The Compensation Committee is authorized to delegate its authority to subcommittees as determined to be necessary or advisable. A current version of the Compensation Committee charter is available on the Company’s website at www.trex.com/our-company/corporate-governance/committees-charters/.

Nominating/Corporate Governance Committee. During 2025, the Nominating/Corporate Governance Committee was composed of five non-employee directors, all of whom meet the independence and expertise requirements of the NYSE listing standards: Ms. Robinson who is currently Chairwoman, Ms. Juster, Mr. Keffer, Ms. Lovett, and Mr. Volas. The Nominating/Corporate Governance Committee held five meetings during 2025.

The Nominating/Corporate Governance Committee operates under a written charter that is reviewed annually. The Nominating/Corporate Governance Committee is responsible for recommending candidates for election to the Board and for making recommendations to the Board regarding corporate governance matters, including Board size and membership qualifications, Board committees, corporate organization, and non-employee director compensation, and for succession planning for officers and key executives, performance evaluations of the CEO and other officers, programs for training and development of executive-level employees, and stockholder proposals regarding these matters. Also, the Nominating/Corporate Governance Committee oversees the Company’s Sustainability matters that are significant to the Company and periodically reviews the Company’s Sustainability strategy, initiatives, and policies, and receives quarterly updates from management on Sustainability activities.

The Nominating/Corporate Governance Committee has the authority to retain and terminate any search firm engaged to identify director candidates, and to obtain advice and assistance from outside counsel and any other advisers, as it deems appropriate in its sole discretion. The Nominating/Corporate Governance Committee is authorized to delegate its authority to subcommittees as determined to be necessary or advisable. A current version of the Nominating/Corporate Governance Committee charter is available on the Company’s website at www.trex.com/our-company/corporate-governance/committees-charters/.

Our Board recognizes the importance of effective risk oversight in running a successful business and in fulfilling its fiduciary responsibilities to the Company and its stockholders. While the CEO and other members of our senior leadership team are responsible for the day-to-day management of risk, our Board is responsible for ensuring that an appropriate culture of risk management exists within the Company and for setting the right “tone at the top,” overseeing our aggregate risk profile, and assisting management in addressing specific risks, such as strategic and competitive risks, financial risks, brand and reputation risks, legal risks, regulatory risks, and operational risks.

The Board believes that its current leadership structure best facilitates its oversight of risk by combining independent leadership, through an independent Lead Independent Director, independent board committees, and majority independent board composition, with an experienced Chairman and an experienced CEO who each have extensive knowledge of our business, history, and the complex challenges we face. The CEO’s in-depth understanding of these matters and involvement in the day-to-day management of the Company uniquely positions him to promptly identify and raise key business risks to the Board, call special meetings of the Board (in his capacity as President) when necessary to address critical issues, and focus the Board’s attention on areas of concern. The Chairman, Lead Independent Director, independent committee chairs, and other directors also are experienced executives who can and do raise issues for Board consideration and review, and are not hesitant to challenge management. The Board believes there is a well-functioning and effective balance between the Chairman, Lead Independent Director, independent board committees, independent board members, and the CEO, which enhances risk oversight.

The Board exercises its oversight responsibility for risk both directly and through its three standing committees. Throughout the year, the Board and each committee spend a portion of their time reviewing and discussing specific risk topics. The full Board is kept informed of each committee’s risk oversight and related activities through regular attendance at all committee meetings by all directors. Strategic, operational, and competitive risks also are presented and discussed at the Board’s quarterly meetings, and more often as needed. On at least an annual basis, the Board conducts a review of our long-term strategic plans and members of senior management report on our top risks and the steps management has taken or will take to mitigate these risks. At each quarterly meeting, or more often as necessary, our CEO provides written and/or oral reports to the Board on the critical issues we face, and each officer reports on recent developments in their respective operating area. These reports include a discussion of business risks as well as a discussion regarding enterprise risk. In addition, at each quarterly meeting, or more often as necessary, the Senior Vice President, Chief Legal Officer, Secretary and Chief Sustainability Officer (“CLO”) updates the Board on material legal and regulatory matters.

The Audit Committee is responsible for reviewing the framework by which management discusses our risk profile and risk exposures with the full Board and its committees. The Audit Committee meets regularly with our CFO, independent registered public accounting firm, internal auditor, CLO, and other members of senior management to discuss our major financial risk exposures, financial reporting, internal controls, credit and liquidity risk, compliance risk, and key operational risks. The Audit Committee meets regularly in separate executive sessions

with the independent registered public accounting firm and internal auditor, as well as with committee members only, to facilitate a full and candid discussion of risk and other matters.

The Compensation Committee is responsible for overseeing human capital and compensation risks, including evaluating and assessing risks arising from our compensation policies and practices and ensuring executive compensation is aligned with performance. The Compensation Committee is also charged with monitoring our incentive and equity-based compensation plans, including employee benefit plans, reviewing and retaining compensation advisers, and considering the results of the non-binding advisory say-on-pay vote and determine what adjustments, if any, are necessary or appropriate for the Company to make to its compensation policies and practices in light of the results of such vote. The Compensation Committee meets regularly with the CLO and other executive officers as well as in separate sessions with the Company’s external compensation consultant to facilitate a full and candid discussion of executive performance and compensation.

The Nominating/ Corporate Governance Committee oversees risks related to our overall corporate governance, including Board and committee composition, Board size and structure, Board compensation, director independence, our corporate governance profile and ratings and sustainability-related strategies, initiatives and policies. The Committee also is actively engaged in overseeing risks associated with succession planning for the Board and management.

The Board of Directors, its committees and the Company's management recognize the importance of Sustainability matters and how they impact our stakeholders. During 2025, the Company continued its focus on several Sustainability initiatives that matter to our customers, employees, communities, stockholders and the environment. We believe appropriately responding to Sustainability matters is an important component of corporate social responsibility and comprehensive fiscal management. Considering the continued importance surrounding Sustainability matters, the Company is active in establishing and improving programs, practices and policies to maximize the benefit to the Company, our stockholders, employees, customers and the communities we impact. We believe that strong Sustainability programs and practices are critical to attracting the best talent, executing on our strategies, maintaining a robust supplier and channel partner base, and innovating to meet our consumers’ evolving expectations.

The Company’s policies, practices and programs include engagement with external stakeholders to learn about their priorities and get their feedback; coordination of relevant company projects and initiatives; and alignment with the Company’s strategies and implementation.

Further, the Board and its committees review and discuss with management matters related to human capital management, including employee engagement, compensation and benefits, business conduct and compliance, and executive succession planning.

We are committed to conducting operations and activities in a manner that provides and maintains safe and healthy working conditions, protects the environment, and conserves natural resources. It is our policy that no employee shall engage in any conduct that violates any environmental, health or safety law or is otherwise inconsistent with the health and safety needs of our employees and the environmental needs of our communities. We are also committed to the continual improvement of our environmental management systems, our environmental, health and safety programs, and to the prevention of pollution.

On June 30, 2025, the Company published its seventh annual Sustainability Report that highlighted several achievements including:

The Company is committed to continuing its Sustainability efforts and will continue its communications with customers, employees, communities, and stockholders regarding its sustainability initiatives in the upcoming 2025 Sustainability Report. A copy of the Company’s current Sustainability report is available on the Company’s website at www.trex.com/why-trex/sustainability/.

In connection with the Company’s Sustainability efforts, in addition to our Code of Conduct and Ethics, the Company has adopted a Human Rights Policy, a Vendor and Customer Code of Conduct and Ethics, an Environmental Policy, and an Occupational Health and Safety Policy. A current version of each of these policies is available on the Company’s website at www.trex.com/our-company/.

No member of the Compensation Committee was an officer or employee of the Company or any subsidiary of the Company during 2025. There are no interlock relationships as defined in the applicable SEC rules.

The Board has adopted a director nominations policy (the “nominations policy”). The purpose of the nominations policy is to set forth the process by which candidates for directors are selected. The nominations policy is administered by the Nominating/Corporate Governance Committee of the Board.

The Board does not currently prescribe any minimum qualifications for director candidates. Consistent with the criteria for the selection of directors approved by the Board, the Nominating/Corporate Governance Committee will take into account the Company’s current needs and the qualities needed for Board service, including experience and achievement in business, finance, technology or other areas relevant to the Company’s activities; reputation, ethical character and maturity of judgment; diversity of viewpoints, backgrounds, and experiences; absence of conflicts of interest that might impede the proper performance of the responsibilities of a director; independence under SEC and NYSE rules; service on other boards of directors; sufficient time to devote to Board matters; ability to work effectively and collegially with other Board members; and diversity. In considering the diversity of candidates, the Committee considers a range of factors including an individual’s background, viewpoints, professional experience, education, and skills. In the case of incumbent directors whose terms of office are set to expire, the Nominating/Corporate Governance Committee will review such directors’ overall service to the Company during their term, including the number of meetings attended, level of participation, quality of performance, and any transactions of such directors with the Company during their term. For those potential new director candidates who appear upon first consideration to meet the Board’s selection criteria, the Nominating/Corporate Governance Committee will conduct appropriate inquiries into their background and qualifications and, depending on the result of such inquiries, arrange for in-person meetings with the potential candidates.

The Nominating/Corporate Governance Committee may use multiple sources for identifying director candidates, including its own contacts and referrals from other directors, members of management, and the Company’s advisers. The Nominating/Corporate Governance Committee has used in the past, and may use in the future, the services of an executive search firm to help identify candidates for directors who meet the qualifications outlined above. The search firm screens the candidates, conducts reference checks, prepares a biography of each candidate for committee review, and assists in arranging interviews.

The Committee will also consider director candidates recommended by stockholders and will evaluate such director candidates in the same manner in which it evaluates candidates recommended by other sources. In making recommendations for director nominees for the annual meeting of stockholders, the Nominating/Corporate Governance Committee will consider any written recommendations of director candidates by stockholders received by the Secretary of the Company in accordance with the provisions of the Company’s bylaws and applicable law.

The nominations policy is intended to provide a flexible set of guidelines for the effective functioning of the Company’s director nominations process. The Nominating/Corporate Governance Committee intends to review the nominations policy as it considers advisable and anticipates that modifications may be necessary from time to time as the Company’s needs and circumstances evolve, and as applicable legal or listing standards change. The Nominating/Corporate Governance Committee may amend the nominations policy at any time.

The Company’s bylaws provide that any stockholder wishing to nominate persons for election as directors at an annual meeting must deliver to the Secretary of the Company at the Company’s principal office in Winchester, Virginia a written notice of the stockholder’s intention to make such a nomination. The stockholder generally is required to furnish the notice no earlier than 120 days and no later than 90 days before the first anniversary of the preceding year’s annual meeting. The notice must contain the information required by the Company’s bylaws.

The Board welcomes communications from its stockholders and other interested parties and has adopted a procedure for receiving and addressing those communications. Security holders and other interested parties may communicate any concerns they may have about the Company directly and confidentially to either the full Board or the non-management directors as a group, or an individual director, by writing to: “Board of Directors” or “Non-Management Directors” or Name of Individual Director, Trex Company, Inc., 2500 Trex Way, Winchester, VA 22601, Attention: Secretary, or by calling the Company’s Governance Hotline (1-800-719-4916). An independent third-party vendor maintains the Governance Hotline, which is available 24 hours a day, 365 days a year. A caller wishing to be identified may indicate his or her name in the message. All calls are forwarded to the CLO/Secretary and CFO. The CLO/Secretary then reviews and forwards all communications to the Board member or members that the caller designates, except for those communications that are outside the scope of Board matters or duplicative of other communications previously forwarded to the intended recipients. The CLO/Secretary will retain copies of all communications and maintain a record of whether the communications were forwarded and, if not, the reason why not.

Any individual, whether an employee or third party, may report to the Audit Committee any information relating to questionable accounting, internal accounting controls, and auditing matters by writing to Trex Company, Inc., Audit Committee Chairman, c/o Woods Rogers PLC, 901 East Byrd Street, Suite 1550, Richmond, VA 23219, or by calling the Company’s Governance Hotline. As stated above, an independent third-party vendor maintains the Governance Hotline. A caller wishing to be identified may indicate his or her name in the message. All calls are forwarded to the Chairman of the Audit Committee. If anyone wants to submit relevant records, they should be mailed to the above address.

We proactively engage with shareholders and other stakeholders throughout the year to learn their perspectives on significant issues, including company performance and strategy, corporate governance, executive compensation, and environmental, social, and governance topics. This engagement helps us better understand shareholder priorities and perspectives, gives us an opportunity to elaborate upon our initiatives and practices, and fosters constructive dialogue. We take feedback and insights from our engagement with shareholders and other stakeholders into consideration as we review and evolve our practices and disclosures, and further share them with our Board as appropriate.

Section 16(a) of the Securities Exchange Act of 1934 requires the Company’s directors and executive officers and persons who own more than 10% of the Company’s common stock to file with the SEC and the NYSE initial reports of ownership and reports of changes in ownership of common stock and other equity securities of the Company. The reporting persons are required by rules of the SEC to furnish the Company with copies of all Section 16(a) reports they file. Based solely upon a review of Section 16(a) reports furnished to the Company for fiscal 2025 or written representations that no other reports were required, the Company believes that the foregoing reporting persons complied with all filing requirements for fiscal 2025.

We have adopted a Code of Conduct and Ethics, which is applicable to all of our directors, officers, and employees, including our CEO and CFO. We make this available on our website, at www.trex.com/our-company/corporate-governance/, and in print, to any stockholder who requests them, copies of our Code of Conduct and Ethics, our Bylaws, our Corporate Governance Principles and the Charters of each standing committee of our Board. Requests for copies of these documents should be directed to Secretary, Trex Company, Inc., 2500 Trex Way, Winchester, Virginia 22601. To the extent required by SEC rules, we intend to disclose any amendments to our Code of Conduct and Ethics, and any waiver of a provision of the code with respect to our principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions, on our website referred to above within four business days following any such amendment or waiver, or within any other period that may be required under SEC rules from time to time.

Non-Employee Director Compensation

Non-employee directors of the Company receive cash and stock-based compensation under the Trex Company, Inc. Amended and Restated 1999 Incentive Plan for Outside Directors (“Outside Director Plan”). The Outside Director Plan is administered by the Nominating/Corporate Governance Committee of the Board. The Outside Director Plan provides that all equity grants issued under such Plan are issued pursuant to the 2023 Stock Incentive Plan, which was approved by stockholders at the Company’s 2023 annual meeting.

The Nominating/Corporate Governance Committee is responsible for making recommendations to the Board regarding non-employee director compensation. In accordance with this authority, the Nominating/Corporate Governance Committee utilizes the Compensation Committee’s independent compensation consultant, Korn/Ferry International (“KF”), to advise the Nominating/Corporate Governance Committee on matters related to director compensation.

The review conducted by the Nominating/Corporate Governance Committee in July 2024 indicated that the non-employee directors’ total annual compensation (consisting of cash and equity-based compensation) was approximately 99% of the median of the peer group (assuming a hypothetical director serves as a member of the Audit Committee and the Compensation Committee). The Nominating/Corporate Governance Committee, desiring that non-employee directors’ total annual compensation be aligned with the peer group, recommended no changes in compensation to the Board for 2025. For the hypothetical director referred to above, the total annual compensation was maintained at $222,500.

The elements of the non-employee director compensation package under the Outside Director Plan are as follows:

The Nominating/Corporate Governance Committee has elected to use restricted stock units as the form of equity described above.

The Outside Director Plan is designed to deliver compensation approximately 46% in cash and 54% in equity (assuming a director does not elect to receive additional equity in lieu of cash, as described above), with the objective of appropriately balancing the pay of non-employee directors for their service while linking their compensation closely to returns to stockholders through the potential for enhanced value from future stock price appreciation. Directors are also reimbursed for actual travel expenses.

The Company does not provide pensions, medical benefits, or other benefit programs to non-employee directors.

In 2013, the Board adopted Stock Ownership Guidelines applicable to non-employee directors, pursuant to which each non-employee director is required to own and hold, as a minimum, that number of shares of the Company’s common stock having a market value of at least three times the director’s annual cash retainer. For purposes of the guidelines, common stock includes shares of common stock no matter how acquired (i.e., vesting of restricted shares or restricted stock units, or purchased on the open market), and unvested restricted shares and restricted stock units. Directors have five years from becoming a director to comply with the ownership requirements. Other than Ms. Tasi who joined the Board in February 2026, each director meets the current minimum requirements.

In 2013, the Board also adopted, on a voluntary basis and in advance of final Dodd-Frank Act hedging rules, an Anti-Hedging and Anti-Pledging Policy that applies to non-employee directors. This policy prohibits our directors from purchasing any financial instrument or entering into any transaction that is designed to hedge or offset any decrease in the market value of Company equity (including, but not limited to, prepaid variable forward contracts, equity swaps, collars, or exchange funds), or pledging, hypothecating, or otherwise encumbering Company equity as collateral for indebtedness.

(See discussion in Compensation Discussion and Analysis under the “Stock Ownership Guidelines” and “Anti-Hedging and Anti-Pledging Policy” sections under “Additional Information on Our Program” for discussion of the Stock Ownership Guidelines and Anti-Hedging and Anti-Pledging Policy as applicable to our named executive officers.)

2025 Non-Employee Director Compensation

The table below shows compensation paid to the non-employee directors for their service in 2025.