UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 10-K

(Mark One)

For the fiscal year ended December 31, 2017

For the transition period from                 to                

Commission file number: 001-14649

Trex Company, Inc.

(Exact name of registrant as specified in its charter)

(540) 542-6300

Registrant’s telephone number, including area code:

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act:

None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  ☐    No  ☒

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Exchange Act.    Yes  ☐    No  ☒

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  ☒    No  ☐

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate web site, if any, every Interactive Data File required to be submitted and posed pursuant to Rule 405 of Regulation S-T during the preceding 12 months.    Yes  ☒    No  ☐

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.  ☒

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting Company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting Company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act    ☐

Indicate by check mark whether the registrant is a shell Company (as defined in Rule 12b-2 of the Exchange Act).    Yes  ☐    No  ☒

The aggregate market value of the registrant’s common equity held by non-affiliates of the registrant at June 30, 2017, which was the last business day of the registrant’s most recently completed second fiscal quarter, was approximately $2.0 billion based on the closing price of the common stock as reported on the New York Stock Exchange on such date and assuming, for purposes of this computation only, that the registrant’s directors, executive officers and beneficial owners of 10% or more of the registrant’s common stock are affiliates.

The number of shares of the registrant’s common stock outstanding on February 6, 2018 was 29,428,555.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the following documents are incorporated by reference in this Form 10-K as indicated herein:

TABLE OF CONTENTS

i

NOTE ON FORWARD-LOOKING STATEMENTS

This report, including the information it incorporates by reference, contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. We intend our forward-looking statements to be covered by the safe harbor provisions for forward-looking statements in these sections. All statements regarding our expected financial position and operating results, our business strategy, our financing plans, forecasted demographic and economic trends relating to our industry and similar matters are forward-looking statements. These statements can sometimes be identified by our use of forward-looking words such as “believe,” “may,” “will,” “anticipate,” “estimate,” “expect,” “intend” or similar expressions. We cannot promise you that our expectations in such forward-looking statements will turn out to be correct. Our actual results could be materially different from our expectations because of various factors, including the factors discussed under “Item 1A. Risk Factors” in this report.

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PART I

Some of the information contained in this report concerning the markets and industry in which we operate is derived from publicly available information and from industry sources. Although we believe that this publicly available information and the information provided by these industry sources are reliable, we have not independently verified the accuracy of any of this information.

General

Trex Company, Inc. (Company, we, us or our), was incorporated as a Delaware corporation in 1998. The Company is the world’s largest manufacturer of wood-alternative decking and railing products, which are marketed under the brand name Trex^® and manufactured in the United States, and a leading national provider of custom-engineered railing systems and one of the leading suppliers of staging equipment. Our principal executive offices are located at 160 Exeter Drive, Winchester, Virginia 22603, and our telephone number at that address is (540) 542-6300.

Products

Operations and Products: Trex Company, Inc. currently operates in two reportable segments: Trex Residential Products and Trex Commercial Products.

Trex Residential Products is the world’s largest manufacturer of high-performance composite decking and railing products, which are marketed under the brand name Trex^® and manufactured in the United States. We offer a comprehensive set of aesthetically appealing and durable, low-maintenance product offerings in the decking, railing, fencing, trim, steel deck framing, and outdoor lighting categories. A majority of the products are eco-friendly and made in a proprietary process that combines reclaimed wood fibers and recycled polyethylene film. Trex Residential products are sold to distributors and two national retailers who, in turn, sell primarily to the residential market.

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Trex offers the following Trex Residential products:

Trex Residential Products offer a number of significant aesthetic advantages over wood while eliminating many of wood’s major functional disadvantages, which include warping, splitting and other damage from moisture. In addition to resisting fading and surface staining, Trex Residential products require no sanding, staining or sealing, resist moisture damage, provide a splinter-free surface and do not require chemical treatment against rot or insect infestation. Special characteristics (including resistance to splitting, the ability to bend, and ease and consistency of machining and finishing) facilitate installation, reduce contractor call-backs and afford consumers a wide range of design options. Combined, these aspects yield significant aesthetic advantages and lower maintenance than wood decking and railing and ultimately render Trex Residential products less costly than wood over the life of the deck. Trex decking products do not have the tensile strength of wood and, as a result, are not used as primary structural members in posts, beams or columns used in a deck’s substructure. However, Trex does offer the Trex Elevations steel deck framing system.

We have received product building code listings from the major U.S. building code listing agencies for decking and railing and from the major Canadian building code listing agency for decking. The listings facilitate the acquisition of building permits by deck builders and promote consumer and industry acceptance of our products as an alternative to wood decking.

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We are a licensor in a number of licensing agreements with third parties to manufacture and sell products under the Trex trademark. Our licensed products are:

Trex Commercial Products is a leading national provider of custom-engineered railing systems and one of the leading suppliers of staging equipment. Trex Commercial Products designs and engineers custom railing solutions, which are prevalent in professional and collegiate sports facilities, standardized architectural and aluminum railing systems, which target commercial and high-rise applications, and portable staging equipment for the performing arts, sports, and event production and rental markets. With a team of devoted engineers, and industry-leading reputation for quality and dedication to customer service, Trex Commercial Products are sold through architects, specifiers, and contractors.

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Trex offers the following Trex Commercial products:

Customers and Distribution

Trex Residential Products: Wholesale Distributors/Retail Lumber Dealers. We generate most of our sales for our wood-alternative decking and railing products through our wholesale distribution network by selling Trex products to wholesale distributors, who in turn, sell our products to retail lumber outlets. These retail dealers market to both homeowners and contractors, but they emphasize sales to professional contractors, remodelers and homebuilders. Contractor-installed decks generally are larger installations with professional craftsmanship. Our retail dealers generally provide sales personnel trained in Trex products, contractor training, inventory commitment and point-of-sale display support. We believe that attracting wholesale distributors, who are committed to our products and marketing approach and can effectively sell higher value products to contractor-oriented lumber yards and other retail outlets, is important to our future growth. Our distributors are able to provide value-added service in marketing our products because they sell premium wood decking products and other innovative building materials that typically require product training and personal selling efforts. We typically appoint two distributors on a non-exclusive basis to distribute Trex products within a specified area. The distributor purchases our products at prices in effect at the time we ship the product to the distributor. Sales to two of our distributors, Boise Cascade Company and U.S. Lumber Group, LLC, each exceeded 10% of gross sales in 2017.

Home Depot and Lowe’s. We sell our products through Home Depot and Lowe’s stores. Home Depot and Lowe’s purchase products directly from us for stocking on their shelves. They also purchase product through our wholesale distributors for special orders placed by consumers. Home Depot and Lowe’s serve both the contractor market and the “do-it-yourself” market. We believe that brand exposure through Home Depot and Lowe’s distribution promotes consumer acceptance of our products.

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Trex Commercial Products: We sell our modular and architectural railing systems and solutions for the commercial and multifamily markets and our staging, acoustical and seating systems for sports stadiums and performing arts venues primarily to facility owners and general contractors throughout the country. We market these products through our direct sales staff, independent sales representatives, and bidding on projects.

Manufacturing Process

Products manufactured at our Winchester, Virginia and Fernley, Nevada manufacturing facilities are primarily manufactured from reclaimed wood fiber and scrap polyethylene. Our primary manufacturing process for the products involves mixing wood particles with plastic, heating and then extruding, or forcing, the highly viscous and abrasive material through a profile die. We use many proprietary and skill-based advantages in our manufacturing process. Products manufactured at our Minnesota manufacturing facility are primarily manufactured from aluminum and stainless steel. Our primary manufacturing process for these products involves cutting, machining, welding and finishing. We use Six Sigma and Lean Manufacturing methodologies throughout our Company within our plant operations and in the planning and execution of projects that are important to our success.

Our manufacturing processes require significant capital investment, expertise and time to develop. We have continuously invested the capital necessary to expand our manufacturing throughput and improve our manufacturing processes. We have also broadened the range of raw materials that we can use to produce a consistent and high-quality finished product. In connection with national building code listings, we maintain a quality control testing program.

Suppliers

The Company’s purchasing department is responsible for ensuring that purchases are made from sources that operate with ethical and responsible business practices. We conduct supply chain assessments when considered necessary in relation to the significance of the purchase and business opportunity for the Company. Assessments include in-person reviews and tours of operating facilities.

The production of most of our decking products requires a supply of reclaimed wood fiber and scrap polyethylene. We fulfill requirements for raw materials under both purchase orders and supply contracts. In the year ended December 31, 2017, we purchased substantially all of our reclaimed wood fiber requirements under purchase orders, which do not involve long-term supply commitments. All of our polyethylene purchases are under short-term supply contracts that generally have a term of approximately one to two years for which pricing is negotiated as needed, or under purchase orders that do not involve long-term supply commitments.

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In addition, we outsource the production of certain products to third-party manufacturers.

The production of our commercial staging and railing products requires a supply of aluminum, stainless steel and glass components. We use multiple sources for each material to ensure consistent availability of material and competitive pricing. We purchase substantially all of our aluminum, stainless steel and glass under purchase orders, which do not involve long-term supply commitments.

Research and Development and Training

We maintain research and development operations in the Trex Technical Center in Winchester, Virginia and at our Minnesota location. Our research and development efforts focus on innovation and developing new products, lowering the cost of manufacturing our existing products and redesigning existing product lines to increase efficiency and enhance performance. For the years ended December 31, 2017, 2016 and 2015, research and development costs were $3.8 million, $3.7 million, and $1.5 million, respectively, and have been included in “Selling, general and administrative expenses” in the accompanying Consolidated Statements of Comprehensive Income.

During 2016, we launched Trex University, our state-of-the-art training facility located near our Winchester manufacturing plant. Trex University is designed to educate and train retailers, contractors and other partners on the benefits of Trex aesthetically pleasing, high performance and low maintenance outdoor living products.

Growth Strategies

Our long-term goal is to perpetuate our position as the leading producer of branded superior wood-alternative outdoor living products by increasing our market share and expanding into new product categories and geographic markets through the design, creation and marketing of high-performance outdoor living products that offer superior aesthetics and quality. Also, we will explore opportunities that leverage our manufacturing and extrusion expertise and are tied to our recycling heritage. To attain these goals, we intend to employ the following long-term strategies:

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Competition

Our primary competition for our wood-alternative decking and residential railing products consists of wood products, which constitutes a substantial majority of decking and railing sales, as measured by linear feet of lumber. Many of the conventional lumber suppliers with which we compete have established ties to the building and construction industry and have well-accepted products. A majority of the lumber used in wood decks is pressure-treated lumber. Southern yellow pine and fir have a porosity that readily allows the chemicals used in the pressure treating process to be absorbed. The same porosity makes southern yellow pine susceptible to absorbing moisture, which causes the lumber to warp, crack, splinter and expel fasteners. In addition to pine and fir, other segments of wood material for decking include redwood, cedar and tropical hardwoods, such as ipe, teak and mahogany. These products are often significantly more expensive than pressure-treated lumber, but do not eliminate many of the disadvantages of other wood products.

In addition to wood, we also compete with other manufacturers of wood-alternative products. Industry studies indicate that we have the leading market share of the wood-alternative segment of the decking and railing market. Our principal competitors include Advanced Environmental Recycling Technologies, Inc., The Azek Company, and Fiberon, LLC.

Our ability to compete depends, in part, on a number of factors outside our control, including the ability of our competitors to develop new wood-alternative decking and railing products that are competitive with our products. We believe that the principal competitive factors in the decking and railing market include product quality, price, aesthetics, maintenance cost, and distribution and brand strength. We believe we compete favorably with respect to these factors. We believe that our products offer aesthetic and cost advantages over the life of a deck when compared to other types of decking and railing materials. Although a contractor-installed deck built with Trex products using a pressure-treated wood substructure generally costs more than a deck made entirely from pressure-treated wood, Trex products are low maintenance compared to the on-going maintenance required for a pressure-treated deck and are, therefore, less costly over the life of the deck. We believe that our manufacturing process and utilization of relatively low-cost raw material sources provide us with a competitive cost advantage relative to other manufacturers of wood-alternative decking and railing products. The scale of our operations also confers cost efficiencies in manufacturing, sales and marketing.

Our primary competition for our staging and railing products in the commercial and multi-family markets consists of companies that provide components to assemble guard rails, including C.R. Laurence Co., Inc., a CRH Group company, regional railing and metal fabrication, and Wenger Corporation. Our ability to compete depends on our product design advantages, relationships with architects and general contractors, and competitive manufacturing costs.

Seasonality

Our operating results have historically varied from quarter to quarter. Seasonal, erratic or prolonged adverse weather conditions in certain geographic regions reduce the level of home improvement and construction activity and can shift demand for our products to a later period. As part of our normal business practice and consistent with industry practice, we have historically offered incentive programs to our distributors and dealers to build inventory levels before the start of the prime deck-building season in order to ensure adequate availability of our product to meet anticipated seasonal consumer demand. The seasonal effects are often offset by the positive effect of the incentive programs.

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Government Regulation

We are subject to federal, state and local environmental regulation. The emissions of particulates and other substances from our manufacturing facilities must meet federal and state air quality standards implemented through air permits issued to us by the Department of Environmental Quality of the Commonwealth of Virginia, and the Division of Environmental Protection of Nevada’s Department of Conservation and Natural Resources. Our facilities are regulated by federal and state laws governing the disposal of solid waste and by state and local permits and requirements with respect to wastewater and storm water discharge. Compliance with environmental laws and regulations has not had a material adverse effect on our business, operating results or financial condition.

Our operations also are subject to work place safety regulation by the U.S. Occupational Safety and Health Administration, the Commonwealth of Virginia, and the States of Nevada, Minnesota and South Carolina. Our compliance efforts include safety awareness and training programs for our production and maintenance employees.

Intellectual Property

Our success depends, in part, upon our intellectual property rights relating to our products, production processes and other operations. We rely upon a combination of trade secret, nondisclosure and other contractual arrangements, and patent, copyright and trademark laws, to protect our proprietary rights. We have made substantial investments in manufacturing process improvements that have enabled us to increase manufacturing line production rates, facilitate our development of new products, and produce improvements in our existing products’ dimensional consistency, surface texture and color uniformity.

Intellectual property rights may be challenged by third parties and may not exclude competitors from using the same or similar technologies, brands or works. We seek to secure effective rights for our intellectual property, but cannot provide assurance that third parties will not successfully challenge, or avoid infringing, our intellectual property rights.

We consider our trademarks to be of material importance to our business plans. The U.S. Patent and Trademark Office has granted us federal registrations for many of our trademarks. Federal registration of trademarks is effective for as long as we continue to use the trademarks and renew their registrations. We do not generally register any of our copyrights with the U.S. Copyright Office, but rely on the protection afforded to such copyrights by the U.S. Copyright Act. This law provides protection to authors of original works, whether published or unpublished, and whether registered or unregistered.

We hold a number of U.S. Patents and U.S. Patent Applications for various technologies. We have one current U.S. Patent Application for decking technology and five U.S. Patents, as well as two pending U.S. Patent Applications, for various staging systems, accessories and related technologies. We intend to maintain our existing patents in effect until they expire as well as to seek additional patents as we consider appropriate.

We enter into confidentiality agreements with our employees and limit access to and distribution of our proprietary information. If it is necessary to disclose proprietary information to third parties for business reasons, we require that such third parties sign a confidentiality agreement prior to any disclosure.

Employees and Corporate Governance

At December 31, 2017, we had approximately 1,120 full-time employees, approximately 815 of whom were employed in our manufacturing operations. Our employees are not covered by collective bargaining agreements. We believe that our relationships with our employees are favorable. The Company has internal standards related to hiring practices that encourage diversity, formal programs to provide skill development for our employees, and anti-discrimination standards. The Company has not had any serious complaints or claims over the last three years.

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Information related to the Company’s governance and related activities and programs may be found in the Company’s Proxy Statement filed on March 23, 2017 in Schedule 14A. Also, a copy of the Company’s “Code of Conduct and Ethics” (Code) is maintained on the Company’s web site at www.trex.com. The Company has a whistle-blowing policy included in its Code that encourages reporting by employees of activities the employee considers illegal or dishonest. Each employee is notified of the whistle-blowing policy and a toll-free hotline is provided for reporting issues directly to the Board of Directors and the Company’s General Counsel.

Environmental and Occupational Safety

Environmental

The Company’s commitment to managing environmental impact includes developing and offering more sustainable products to the market as well as reducing the environmental impact of its corporate activities. From continuous improvement in its manufacturing practices that reduce the use of energy to making products using industry leading high levels of recycled materials, the Company is able to improve its use of resources, its greenhouse gas emissions, and its waste streams. Environmental matters relevant to the Company’s operations are the responsibility of members of the executive management team, including the President and Chief Executive Officer, the Chief Financial Officer, the Vice President Operations, and the General Counsel.

Trex’s eco-friendly composite decking products consist of a blend of 95 percent recycled wood and recycled plastic film. Trex uses locally sourced reclaimed wood that would otherwise end up in a landfill. An average 500-square foot composite Trex deck contains 140,000 recycled plastic bags, which makes Trex one of the largest plastic bag recyclers in the U.S. In addition, Trex’s proprietary, eco-friendly processing method eliminates the use of smoke stacks and our bi-coastal factories reduce fuel consumption and CO2 emissions. Almost 100 percent of our factory runoff and refuse are recycled back into the manufacturing line. Any product that does not meet quality specifications is reprocessed, which eliminates the need for landfill. In addition, it is Trex’s goal to provide eco-friendly products for the architectural railing market and promote an effort for design innovation that decreases the environmental footprint.

The Company’s primary resource usage consists of water, natural gas and electricity. The Company develops budgets and plans that improve shareholder return by ensuring the optimal use of each resource, which promotes resource efficiency and minimal waste of the resource. We ensure that all of our manufacturing facilities meet emission standards for the locality in which they operate, and certify to applicable authorities that our emissions are within the relevant locality’s standards.

Market Recognition of Trex Brand’s Environmental Characteristics

The Company’s internal standards for environmental stewardship and product integrity are recognized year-over-year in the marketplace. In 2016, Trex was honored as Environmental Vendor of the Year by The Home Depot. For the past 10 years Trex has won awards in the BUILDER trade magazine’s Brand Use Study across numerous award categories. For the past 5 years, Trex has been an award recipient in the Green Builder trade magazine across numerous categories.

Our decking products meet LEED requirements for builders and our commercial products have contributed to the LEED certifications of some high profile venues. LEED is a point-based system created in part by the U.S. Green Building Council and designed to reward points to building projects that incorporate efficient, and safe eco-friendly products, leading to a building’s designation as LEED Silver, Gold or Platinum. LEED buildings attract higher demand, premium rates and longer occupancy leases, thereby supporting continued and growing demand for products that can facilitate LEED designations. As a U.S. Green Building Council member, Trex works along with council members to transform the way buildings and communities are designed, built and operated with the goal of creating environmentally and socially responsible spaces that improve the quality of life.

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Occupational Safety

The Company applies industry best-practices for monitoring and reporting near misses, lost days and frequency of incidents and for implementing safety systems similar to OHSAS 18001 including:

The Company’s “Design for Safety” program incorporates reviewing and building safety into every project from conception through completion, beginning with a Pre-startup Safety Review (PSSR) that ensures safety items are addressed. A fully empowered Plant Safety Committee performs safety audits and observations, reviews and trends all incidents, writes their own Safety Work Orders, and participates in all PSSRs. Each member is required to successfully complete an Occupational Safety and Health Training course in General Industry Safety and Health, which is sanctioned and accredited by the U.S. Department of Labor/Occupational Safety and Health Administration. In addition, each manufacturing operation has an Employee Health and Safety Manager who is a Certified Occupational Safety Specialist and Certified Occupational Safety Manager.

In addition, the Company is a member of the Voluntary Protection Program Participants Association, the National Safety Council, and the National Fire Protection Association.

Web Sites and Additional Information

The U. S. Securities and Exchange Commission (SEC) maintains an Internet web site at www.sec.gov that contains reports, proxy statements, and other information regarding our Company. In addition, we maintain an Internet corporate web site at www.trex.com. We make available through our web site our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and all amendments to those reports, as soon as reasonably practicable after we electronically file with or furnish such material to the SEC. We do not charge any fees to view, print or access these reports on our web site. The contents of our web site are not a part of this report.

Our business is subject to a number of risks, including the following:

We may not be able to grow unless we increase market acceptance of our products, compete effectively and develop new products and applications.

Our primary competition consists of wood products, which constitute a substantial majority of decking, railing, fencing, and deck framing sales. Since wood-alternative products were introduced to the market in the late 1980s, their market acceptance has increased. Our ability to grow will depend, in part, on our success in continuing to convert demand for wood products into demand for wood-alternative Trex products. To increase our market share, we must overcome:

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Our failure to compete successfully in such markets could have a material adverse effect on our ability to replace wood or increase our market share amongst wood-alternatives. Many of the conventional lumber suppliers with which we compete have established ties to the building and construction industry and have well-accepted products. Our ability to compete depends, in part, upon a number of factors outside our control, including the ability of competitors to develop new alternatives that are more competitive with Trex products.

In addition, substantially all of our revenues are derived from sales of our proprietary wood/polyethylene composite material. Although we have developed, and continue to develop, new products made from other materials, if we should experience significant problems, real or perceived, with acceptance of the Trex wood/polyethylene composite material, our lack of product diversification could have a significant adverse impact on our net sales levels.

Our prospects for sales growth and profitability may be adversely affected if we fail to maintain product quality and product performance at an acceptable cost.

In order to expand our net sales and sustain profitable operations we must maintain the quality and performance of our products. If we are unable to produce high-quality products at standard manufacturing rates and yields, unit costs may be higher. A lack of product performance could impede acceptance of our products in the marketplace and negatively affect our profitability. We continue to receive and settle claims and maintain a warranty reserve related to residential product produced at our Nevada facility prior to 2007 that exhibits surface flaking. We have limited our financial exposure by settling a nationwide class action lawsuit that lessens our exposure to provide replacement product and partial labor reimbursement. However, because the establishment of reserves is an inherently uncertain process involving estimates of the number of future claims and the average cost of claims, our ultimate losses may differ from our warranty reserve. Increases to the warranty reserve and payments for related claims have had a material adverse effect on our profitability and cash flows. Future increases to the warranty reserve could have a material adverse effect on our profitability and cash flows.

A number of class action lawsuits alleging defects in our products have been brought against us, all of which have been settled. In the event future lawsuits relating to alleged product quality issues are brought against us, such lawsuits may be costly and could cause adverse publicity, which in turn could result in a loss of consumer confidence in our products and reduce our sales. Product quality claims could increase our expenses, have a material adverse effect on demand for our products and decrease net sales, net income and liquidity.

Our business is subject to risks in obtaining the raw materials we use at acceptable prices.

The manufacture of our wood-alternative decking and railing products requires substantial amounts of wood fiber and scrap polyethylene. Our business strategy is to create a substantial cost advantage over our competitors by using reclaimed wood fibers and scrap polyethylene. Our ability to obtain adequate supplies of reclaimed wood fibers and scrap polyethylene depends on our success in developing new sources that meet our quality requirements, maintaining favorable relationships with suppliers and managing the collection of supplies from geographically dispersed locations.

Our business could suffer from the termination of significant sources of raw materials, the payment of higher prices for raw materials, the quality of available raw materials, or from the failure to obtain sufficient additional raw materials to meet planned increases in production.

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Certain of our customers account for a significant portion of our sales, and the loss of one or more of these customers could have an adverse effect on our business.

A limited number of our customers account for a significant percentage of our sales. Specifically, sales through our 15 largest customers accounted for approximately 90.0% of gross sales during fiscal years 2017 and 2016, and 89% during fiscal year 2015.

We expect that a significant portion of our sales will continue to be sold through a small number of customers, and certain customers will continue to account for a significant portion of our sales. The loss of a significant customer could have a significant negative impact on our business, results of operations and financial condition.

We have limited ability to control or project inventory build-ups in our distribution channel that can negatively affect our sales in subsequent periods.

The seasonal nature of, and changing conditions in, our industry can result in substantial fluctuations in inventory levels of Trex products carried in our two-step distribution channel. We have limited ability to control or precisely project inventory build-ups, which can adversely affect our net sales levels in subsequent periods. We make the substantial majority of our sales to wholesale distributors, who, in turn, sell our products to local dealers. Because of the seasonal nature of the demand for our products, our distribution channel partners must forecast demand for our products, place orders for the products, and maintain Trex product inventories in advance of the prime deck-building season, which generally occurs in the latter part of the first calendar quarter through the third calendar quarter. Accordingly, our results for the second and third quarters are difficult to predict and past performance will not necessarily indicate future performance. Inventory levels respond to a number of changing conditions in our industry, including product price increases, increases in the number of competitive producers, the rapid pace of product introduction and innovation, changes in the levels of home-building and remodeling expenditures and the cost and availability of consumer credit.

The demand for our products is negatively affected by adverse weather conditions.

Our products are generally purchased shortly before installation and used in outdoor environments. As a result, there is a correlation between the amount of product we sell and weather conditions during the time they are to be installed. Adverse weather conditions may interfere with ordinary construction, delay projects or lead to cessation of construction involving our products. These interferences may shift sales to subsequent reporting periods or decrease overall sales, given the limited decking season in many locations. Prolonged adverse weather conditions could have a negative impact on our results of operations and liquidity.

We depend on third parties for transportation services and the lack of availability of transportation and/or increases in cost could materially adversely affect our business and operations.

Our business depends on the transportation of both finished goods to our distributors and the transportation of raw materials to us. We rely on third parties for transportation of these items. In particular, a significant portion of our finished goods are transported by flatbed trucks, which are occasionally in high demand (especially at the end of calendar quarters) and/or subject to price fluctuations based on market conditions and the price of fuel.

If the required supply of transportation services is unavailable when needed, we may be unable to sell our products at full value, or at all. Similarly, if any of these providers were unavailable to deliver raw materials to us in a timely manner, we may be unable to manufacture our products in response to customer demand. This could harm our reputation, negatively impact our customer relationships and have a material adverse effect on our financial condition and results of operations. In addition, a material increase in transportation rates or fuel surcharges could have a material adverse effect on our profitability.

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The demand for our products is influenced by general economic conditions and could be adversely affected by economic downturns.

The demand for our wood-alternative decking and railing products is influenced by the general health of the economy, the level of home improvement activity and, to a much lesser extent, new home construction. These factors are affected by home equity values, credit availability, consumer confidence and spending habits, employment, interest rates, inflation and general economic conditions. Devaluation in home equity values can adversely affect the availability of home equity withdrawals and result in decreased home improvement spending. We cannot predict general economic conditions or the home remodeling and new home construction environments. Any economic downturn could reduce consumer income or equity capital available for spending on discretionary items, which could adversely affect the demand for our products. The demand for our commercial staging and railing products is influenced by the level of commercial construction activity, building variances, funding availability for large public use facilities, including sports stadiums and arenas, and the construction schedules of our projects.

We have significant capital invested in assets that may become obsolete or impaired and result in a charge to our earnings.

We have made and may continue to make significant capital investments to our property plant and equipment in order to improve or expand our manufacturing capabilities. These investments sometimes involve the implementation of new technology and replacement of existing equipment at our manufacturing facilities, which may result in charges to our earnings if the existing equipment is not fully depreciated. We have also made and may continue to make significant capital investments in order to acquire businesses or operations that allow us to diversify into new product markets. These investments may also result in the recognition of goodwill, which may result in an impairment charge to our earnings if circumstances change and reduce the fair value of the goodwill acquired below its carrying amount. Significant replacement of equipment or changes in the expected cash flows related to our assets could result in reduced earnings or cash flows in future periods.

Our ability to continue to obtain financing on favorable terms, and the level of any outstanding indebtedness, could adversely affect our financial health and ability to compete.

Our ability to continue to obtain financing on favorable terms may limit our discretion on some business matters, which could make it more difficult for us to expand, finance our operations and engage in other business activities that may be in our interest. In addition, our senior credit facility may impose operating and financial restrictions.

At certain periods during the year, we borrow significant amounts on our senior credit facility for working capital purposes. In addition, we may borrow on the senior credit facility to pursue strategic opportunities or other general business matters. Accordingly, our future level of indebtedness could have important consequences. For example, it may:

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Our ability to make future principal and interest payments, borrow and repay amounts under our senior credit facility and continue to comply with our loan covenants will depend primarily on our ability to generate sufficient cash flow from operations. Our failure to comply with our loan covenants might cause our lenders to accelerate our repayment obligations under our senior credit facility, which may be declared payable immediately based on a default.

None.

We lease our corporate headquarters in Winchester, Virginia, which consists of approximately 36,000 square feet of office space, under a lease that expires in March 2020. In addition, we lease 55,047 square feet of office and storage space in Dulles, Virginia, that we do not occupy. We have sublet all of the office space in Dulles, Virginia, for the remainder of the term of the lease obligation, which expires in mid-2019.

We own approximately 92 acres of land in Winchester, Virginia and the buildings on this land. The site includes our research and development technical facility and manufacturing facility, which contains approximately 465,000 square feet of space, and outside open storage. We own approximately 37 acres of land in Fernley, Nevada and the buildings on this land. The site includes our manufacturing facility, which contains approximately 240,000 square feet of space, and outside open storage. These facilities provide adequate capacity for current and anticipated future consumer demand.

In September 2007, we suspended operations at our Olive Branch, Mississippi facility (Olive Branch facility) and consolidated all of our manufacturing operations into our Winchester and Fernley sites. In January 2016, we sold a portion of the Olive Branch facility that contained the buildings. As of the date of this report, we continue to own approximately 62 acres of undeveloped land at the Olive Branch facility.

We lease a total of approximately 1.6 million square feet of warehouse and facility space under leases with expiration dates ranging from 2018 to 2026. For information about these leases, see Note 13 to our Consolidated Financial Statements appearing elsewhere in this report. The equipment and machinery we use in our operations consist principally of plastic and wood conveying and processing equipment. We own all of our manufacturing equipment. We lease some forklift equipment at our facilities under operating leases.

We regularly evaluate our various facilities and equipment and make capital investments where necessary. In 2017, we spent a total of $15.0 million on capital expenditures, primarily related to general plant cost reduction initiatives, and equipment and new product development. We estimate that our capital expenditures in 2018 will be approximately $20 million to $25 million. We expect to use these expenditures principally to support cost reduction initiatives, new product launches in current and adjacent categories and general business support.

The Company has lawsuits, as well as other claims, pending against it which are ordinary routine litigation and claims incidental to the business. Management has evaluated the merits of these lawsuits and claims, and believes that their ultimate resolution will not have a material effect on the Company’s consolidated financial condition, results of operations, liquidity or competitive position.

Not applicable.

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PART II

Market for Common Stock

Our common stock has been listed on the New York Stock Exchange (NYSE) since April 8, 1999. Between April 8, 1999 and November 22, 2009, it was listed under the symbol “TWP”. Effective November 23, 2009, the symbol changed to “TREX”. The table below shows the reported high and low sale prices of our common stock for each quarter during 2017 and 2016 as reported by the NYSE.

Dividend Policy

We have never paid cash dividends on our common stock and our credit agreement places limitations on our ability to pay cash dividends. We intend to retain future earnings to finance the development and expansion of our business or the repurchase of our common shares and, therefore, have no current intention to pay cash dividends. However, we reconsider our dividend policy on a regular basis and may determine to pay dividends in the future.

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Stockholder Return Performance Graph

The following graph and table show the cumulative total stockholder return on the Company’s common stock for the last five fiscal years compared to the Russell 2000 Index and the Standard and Poor’s 600 Building Products Index (S&P 600 Building Products). The graph assumes $100 was invested on December 31, 2012 in (1) the Company’s common stock, (2) the Russell 2000 Index and (3) the S&P 600 Building Products, and assumes reinvestment of dividends and market capitalization weighting as of December 31, 2013, 2014, 2015, 2016 and 2017.

Comparison of Cumulative Total Return

Among Trex Company, Inc., Russell 2000 Index, and S&P 600 Building Products Index

Other Stockholder Matters

As of February 6, 2018, there were approximately 174 holders of record of our common stock.

In 2017, we submitted to the NYSE in a timely manner the annual certification that our Chief Executive Officer was not aware of any violation by us of the NYSE corporate governance listing standards.

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The following table presents selected financial data as of December 31, 2017, 2016, 2015, 2014, and 2013 for each year in the five-year period ended December 31, 2017.

The selected financial data should be read in conjunction with “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and our Consolidated Financial Statements and related notes thereto appearing elsewhere in this report.

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The Company compensates for these limitations by relying primarily on its GAAP results to evaluate its operating performance and by considering independently the economic effects of the foregoing items that are not reflected in EBITDA. As a result of these limitations, EBITDA should not be considered as an alternative to net income, as calculated in accordance with GAAP, as a measure of operating performance, nor should it be considered as an alternative to cash flows as a measure of liquidity. The following table sets forth, for the years indicated, a reconciliation of EBITDA to net income:

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This management’s discussion and analysis contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. All statements regarding our expected financial position and operating results, our business strategy, our financing plans, forecasted demographic and economic trends relating to our industry and similar matters are forward-looking statements. These statements can sometimes be identified by our use of forward-looking words such as “may,” “will,” “anticipate,” “estimate,” “expect,” “intend” or similar expressions. We cannot promise you that our expectations in such forward-looking statements will turn out to be correct. Our actual results could be materially different from our expectations because of various factors, including the factors discussed under “Item 1A. Risk Factors.” These statements are also subject to risks and uncertainties that could cause the Company’s actual operating results to differ materially. Such risks and uncertainties include, but are not limited to, the extent of market acceptance of the Company’s current and newly developed products; the costs associated with the development and launch of new products and the market acceptance of such new products; the sensitivity of the Company’s business to general economic conditions; the impact of seasonal and weather-related demand fluctuations on inventory levels in the distribution channel and sales of the Company’s products; the availability and cost of third-party transportation services for our products and raw materials; the Company’s ability to obtain raw materials at acceptable prices; the Company’s ability to maintain product quality and product performance at an acceptable cost; the level of expenses associated with product replacement and consumer relations expenses related to product quality; and the highly competitive markets in which the Company operates.

OVERVIEW

General. Trex Company, Inc. is the world’s largest manufacturer of wood-alternative decking and railing products marketed under the brand name Trex^® and manufactured in the United States. We offer a comprehensive set of aesthetically pleasing, high performance, low maintenance products in the decking, railing, fencing, steel deck framing and outdoor lighting categories. We believe that the range and variety of our products allow consumers to design much of their outdoor living space using Trex brand products.

We offer the following wood-alternative decking and railing products:

In addition, we offer modular and architectural railing systems and solutions for the commercial and multifamily markets and provide staging, acoustical and seating systems for commercial markets, including sports stadiums and performing arts venues.

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Highlights related to the twelve months ended December 31, 2017 include:

Business Acquisition. On July 31, 2017, through our wholly-owned subsidiary, Trex Commercial Products, Inc., we entered into a definitive agreement with SC Company and on that date acquired certain assets and liabilities of SC Company for $71.8 million in cash. We used cash on hand and $30.0 million from our existing revolving credit facility to acquire the business. The acquisition provides us with the opportunity to offer full service railing systems in the growing commercial and multi-family markets, access to a complementary product category with a track record of substantial revenue growth, the ability to achieve economies of scale around raw material procurement, and an increase in the range of products the Company may offer its core customers. The Consolidated Financial Statements include the accounts of Trex Commercial Products from the date of acquisition through December 31, 2017.

Net Sales. Net sales consist of sales and freight, net of returns and discounts. The level of net sales is principally affected by sales volume and the prices paid for Trex wood-alternative decking and railing products. Our branding and product performance enables us to command premium prices over wood products. Our operating results have historically varied from quarter to quarter, often due to seasonal trends in the demand for outdoor living products. Seasonal, erratic or prolonged adverse weather conditions in certain geographic regions reduce the level of home improvement and construction activity and can shift net sales to a later period.

As part of our normal business practice and consistent with industry practices, we have historically provided our distributors and dealers of our wood-alternative decking and railing products incentives to build inventory levels before the start of the prime deck-building season to ensure adequate availability of product to meet anticipated seasonal consumer demand and to enable production planning. These incentives include prompt payment discounts and favorable payment terms. In addition, we offer price discounts or volume rebates on specified products and other incentives based on increases in purchases as part of specific promotional programs. The timing of sales incentive programs can significantly impact sales, receivables and inventory levels during the offering period. However, the timing and terms of the majority of our programs are generally consistent from year to year.

Gross Profit. Gross profit represents the difference between net sales and cost of sales. Cost of sales consists of raw materials costs, direct labor costs, manufacturing costs, warranty costs, and freight. Raw materials costs generally include the costs to purchase and transport reclaimed wood fiber, scrap polyethylene and pigmentation for coloring Trex products. Direct labor costs include wages and benefits of personnel engaged in the manufacturing process. Manufacturing costs consist of costs of depreciation, utilities, maintenance supplies and repairs, indirect labor, including wages and benefits, and warehouse and equipment rental activities.

Selling, General and Administrative Expenses. The largest component of selling, general and administrative expenses is personnel related costs, which include salaries, commissions, incentive compensation, and benefits of

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personnel engaged in sales and marketing, accounting, information technology, corporate operations, research and development, and other business functions. Another component of selling, general and administrative expenses is branding and other sales and marketing costs, which are used to build brand awareness of Trex. These costs consist primarily of advertising, merchandising, and other promotional costs. Other general and administrative expenses include professional fees, office occupancy costs attributable to the business functions previously referenced, and consumer relations expenses. As a percentage of net sales, selling, general and administrative expenses have varied from quarter to quarter due, in part, to the seasonality of our business.

CRITICAL ACCOUNTING POLICIES AND ESTIMATES

Our significant accounting policies are described in Note 2 to our Consolidated Financial Statements appearing elsewhere in this report. Our critical accounting estimates include the areas where we have made what we consider to be particularly difficult, subjective or complex judgments in making estimates, and where these estimates can significantly affect our financial results under different assumptions and conditions. We prepare our financial statements in conformity with accounting principles generally accepted in the United States. As a result, we are required to make estimates, judgments and assumptions that we believe are reasonable based upon the information available. These estimates, judgments and assumptions affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the periods presented. Actual results could be different from these estimates.

Surface Flaking Warranty. We warrant that our residential products will be free from material defects in workmanship and materials. Generally this warranty period is 25 years for residential use and 10 years for commercial use, excluding Trex Signature™ Railing, which has a warranty period of 25 years for both residential and commercial use. We further warrant that Trex Transcend, Trex Enhance, Trex Select and Universal Fascia products will not fade in color more than a certain amount and will be resistant to permanent staining from food substances or mold, provided the stain is cleaned within seven days of appearance. This warranty extends for a period of 25 years for residential use and 10 years for commercial use. If there is a breach of such warranties, we have an obligation either to replace the defective product or refund the purchase price.

We continue to receive and settle claims for products manufactured at our Nevada facility prior to 2007 that exhibit surface flaking and maintain a warranty reserve to provide for the settlement of these claims. Estimating the warranty reserve for surface flaking claims requires management to estimate (1) the number of claims to be settled with payment and (2) the average cost to settle each claim.

To estimate the number of claims to be settled with payment, we utilize actuarial techniques to quantify both the expected number of claims to be received and the percentage of those claims that will ultimately require payment (collectively, elements). Estimates for these elements are quantified using a range of assumptions derived from claim count history and the identification of factors influencing the claim counts. The number of claims received has declined each year since peaking in 2009. The cost per claim varies due to a number of factors, including the size of affected decks, the availability and type of replacement material used, the cost of production of replacement material and the method of claim settlement.

We monitor surface flaking claims activity each quarter for indications that our estimates require revision. Typically, a majority of surface flaking claims received in a year are received during the summer outdoor season, which spans the second and third quarters. It has been our practice to utilize the actuarial techniques discussed above during the third quarter, after a significant portion of all claims has been received for the fiscal year and variances to annual claims expectations are more meaningful. The number of claims received in the year ended December 31, 2017 was lower than claims received in the year ended December 31, 2016, and consistent with our expectations for 2017. Also, the average settlement cost per claim experienced in the year ended December 31, 2017 was lower than the average settlement cost per claim experienced during the year ended December 31, 2016 and consistent with our expectation for 2017. Based on the facts and circumstances at December 31, 2017, we believe our reserve is sufficient to cover future surface flaking obligations. Our analysis

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is based on currently known facts and a number of assumptions, as discussed above, and current expectations. Projecting future events such as the number of claims to be received, the number of claims that will require payment and the average cost of claims could cause the actual warranty liabilities to be higher or lower than those projected, which could materially affect our financial condition, results of operations or cash flows. We estimate that the annual number of claims received will continue to decline over time and that the average cost per claim will increase slightly, primarily due to inflation. If the level of claims received or average cost per claim differs materially from expectations, it could result in additional increases or decreases to the warranty reserve and a decrease or increase in earnings and cash flows in future periods. We estimate that a 10% change in the expected number of remaining claims to be settled with payment or the expected cost to settle claims may result in approximately a $2.8 million change in the surface flaking warranty reserve.

The following table details surface flaking claims activity related to our residential product warranty:

For additional information about product warranties, see Notes 2 and 18 to the Consolidated Financial Statements appearing elsewhere in this report.

Inventories. We account for inventories of our wood-alternative decking and railing products at the lower of cost (last-in, first-out, or LIFO) or market value. At December 31, 2017, the excess of the replacement cost of inventory over the LIFO value of inventory was approximately $20.1 million. Inventories for our staging and commercial railing products are accounted for at the lower of cost (first-in, first-out method) and net realizable value. We believe that our current inventory of finished goods will be saleable in the ordinary course of business and, accordingly, have not established significant reserves for estimated slow moving products or obsolescence.

Goodwill. The Company evaluates the recoverability of goodwill in accordance with Accounting Standard Codification Topic 350, “Intangibles – Goodwill and Other,” annually or more frequently if an event occurs or circumstances change in the interim that would more likely than not reduce the fair value of the asset below its carrying amount. Goodwill is considered to be impaired when the net book value of the reporting unit exceeds its estimated fair value. The Company first assesses qualitative factors to determine if it is more likely than not that the fair value of the reporting unit is less than its carrying amount to determine if it should proceed with the evaluation of goodwill for impairment. If the Company proceeds with the two-step impairment test, the Company first compares the fair value of the reporting unit to its carrying value. If the carrying value of a reporting unit exceeds its fair value, the goodwill of that reporting unit is potentially impaired and step two of the impairment analysis is performed. In step two of the analysis, an impairment loss is recorded equal to the excess of the carrying value of the reporting unit’s goodwill over its implied fair value should such a circumstance arise. The Company measures fair value of the reporting unit based on a present value of future discounted cash flows and a market valuation approach.

Income Taxes. We recognize deferred tax assets and liabilities based on the difference between the financial statement basis and tax basis of assets and liabilities using enacted tax rates in effect during the year in which it is

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expected that the differences reverse. We assess the likelihood that our deferred tax assets will be realized. Deferred tax assets are reduced by a valuation allowance when, after considering all available positive and negative evidence, it is determined that it is more likely than not that some portion, or all, of the deferred tax asset will not be realized. On December 22, 2017, the tax legislation H.R.1, “An Act to Provide for Reconciliation Pursuant to Titles II and V of the Concurrent Resolution on the Budget for Fiscal Year 2018,” known as the Tax Cuts and Jobs Act (Act), was enacted. The Act reduces the corporate tax rate to 21 percent, effective January 1, 2018. Accordingly, we have recognized the tax effects of the Act in our financial statements and related notes as of and for the year ended December 31, 2017. We continue to analyze certain aspects of the Act and refine our calculation, which could potentially affect the measurement of these balances or give rise to new deferred tax amounts. As of December 31, 2017, we have a valuation allowance of $3.1 million against the deferred tax assets related to state tax credits we estimate will expire before they are realized. We will analyze our position in subsequent reporting periods, considering all available positive and negative evidence, in determining the expected realization of our deferred tax assets.

Stock-Based Compensation. The fair value of each stock-based award to officers, directors and certain key employees is established on the date of the grant. We calculate the grant date fair value of stock options and stock appreciation rights using the Black-Scholes valuation model. Determining the fair value of these awards is judgmental in nature and involves the use of significant estimates and assumptions, including the term of the share-based awards, risk-free interest rates over the vesting period, expected dividend rates, and the price volatility of our shares. The Company uses the historical volatility over the average expected term of the options granted as the expected volatility. The Company recognizes forfeitures as they occur. We base our fair value estimates on assumptions we believe to be reasonable but that are inherently uncertain. Actual future results may differ from those estimates.

We grant performance-based restricted stock units, the vesting of which is subject to holder’s continuing employment and our achievement of certain performance measures. At each reporting period, we assess actual performance versus the predetermined performance measures, and adjust the stock-based compensation expense to reflect the relative performance achievement. Actual distributed shares are calculated upon conclusion of the service and performance periods.

RESULTS OF OPERATIONS

Below we have included a discussion of our operating results and material changes in our operating results for the years ended December 31, 2017 compared to December 31, 2016, and December 31, 2016 compared to December 31, 2015.

Year Ended December 31, 2017 Compared To Year Ended December 31, 2016

Net Sales

The 17.8% increase in net sales in the year ended 2017 compared to the year ended 2016 was due primarily to the $63.7 million increase in net sales of our Trex branded decking and railing products. This increase in Residential net sales was positively impacted by continued strength in the remodeling sector, our marketing programs aimed at taking market share from wood, and the healthy demand across our full suite of outdoor living products with decking and railing products as the major growth contributors. The remaining increase resulted

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from the $21.8 million in net sales contributed by our recently acquired commercial products operation for the period from the date of acquisition of July 31, 2017 through year end.

Gross Profit

Gross profit as a percentage of net sales, gross margin, increased to 43.1% in the year ended 2017 from 39.0% in the year ended 2016, an improvement of 4.1%. Gross profit in the year ended 2016 included a $9.8 million increase to the warranty reserve related to surface flaking of our residential product. Excluding this charge, the gross margin for the year ended 2017 increased by 2.0%, reflecting cost reduction initiatives, lower cost raw materials, and increased capacity utilization at our Trex branded decking and railing plants.

Selling, General and Administrative Expenses

The $17.9 million increase in selling, general and administrative expenses in the year ended 2017 compared to the year ended 2016 resulted primarily from a $6.4 million increase in personnel related expenses resulting from the SC Company acquisition and an increase in incentive compensation, a $6.2 million increase in branding and advertising spend in support of our market growth strategies, and a $2.0 million increase in amortization expense related to the intangible assets of our commercial operation that was acquired during 2017. As a percentage of net sales, total selling, general and administrative expenses increased a minimal 0.6% in the year ended 2017 compared to the year ended 2016.

Provision for Income Taxes

We have recognized the tax effects of the Tax Cuts and Jobs Act in our financial statements and related notes as of and for the year ended December 31, 2017. Deferred tax assets that existed as of the enactment date and that are expected to reverse after the Act’s effective date of January 1, 2018 have been adjusted to reflect the new Federal statutory tax rate of 21%. The effect of the change in tax rate on the deferred tax assets and deferred tax liabilities resulted in a tax benefit of $1.9 million for the year ended December 31, 2017, which was allocated to continuing operations. We continue to analyze certain aspects of the Act and refine our calculation, which could potentially affect the measurement of these balances or give rise to new deferred tax amounts. The effective tax rate for the year ended 2017 decreased by 1.0% compared to the effective tax rate for the year ended

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2016 primarily due to enactment of the Tax cuts and Jobs Act and the resulting revaluation of deferred tax assets and liabilities. The Company expects its effective tax rate will decrease in future periods primarily due to the tax effects of the lower Federal statutory rate of 21%, which may be offset by and other changes in the Tax Cuts and Jobs Act, such as the elimination of the domestic manufacturing deduction.

Net Income and Earnings Before Interest, Taxes, Depreciation and Amortization (EBITDA)¹ (in thousands)

Reconciliation of net income (GAAP) to EBITDA (non-GAAP):

The Company uses EBITDA to assess performance as it believes EBITDA facilitates performance comparison between its reportable segments by eliminating interest, taxes, and depreciation and amortization charges to income. Total EBITDA increased 34.7% to $159.1 million for the year ended 2017 compared to $118.1 million for the year ended 2016. The increase in total EBITDA resulted primarily from the increase in Trex Residential EBITDA. The increase in Trex Residential EBITDA was driven by increased net sales resulting primarily from volume growth of our Trex branded decking and railing products. The slight decrease in total EBITDA resulted from Trex Commercial EBITDA, our recently acquired commercial products operation, for the period from the date of acquisition of July 31, 2017 through December 31, 2017, which resulted primarily from the effects of lower margins on certain legacy contracts and $0.5 million in acquisition related expenses.

Year Ended December 31, 2016 Compared to Year Ended December 31, 2015

Net Sales

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The $38.8 million increase in net sales in 2016 compared to 2015 was due primarily to a $53.2 million increase in sales volume growth of our core Trex branded decking and railing products. Sales volume growth also benefited from the execution of our market growth strategies that we launched in the second quarter of this year to highlight the aesthetics, performance and sustainability benefits of Trex composite decking and railing products versus wood. The rollout of our programs in 2016 that aimed to strengthen our brand relationships with consumers and the trade facilitated growth. Such programs include our online tools that assist the consumer throughout the sales process from design to installation, and the launch of our state-of-the-art training facility, Trex University, that educates retailers, contractors and other Trex partners on the benefits of Trex outdoor living products. The increase in sales volume growth was offset by $6.8 million due to the impact of mix and sales discounts, and by a $7.6 million decrease in poly film sales. These sales were curtailed early in 2016 reflecting a change in management’s procurement strategy for scrap poly film purchases.

Gross Profit

The increase in gross profit in 2016 compared to 2015 was primarily due to reduced raw materials cost, execution of our manufacturing cost improvement initiatives, and increased sales. The drivers for the increase in gross margin, or gross profit as a percentage of net sales, were lower raw materials cost mainly resulting from our revised procurement strategy, other cost saving initiatives designed to ensure we meet increased market demand more efficiently and effectively, and from an increase in capacity utilization in order to achieve appropriate inventory levels to support growth, and other operating efficiencies. The increase in gross profit was partially offset by a $9.8 million increase to the legacy warranty reserve related to the surface flaking issue that affected a portion of products produced at our Nevada plant before 2007 compared to a $5.4 million adjustment in 2015 that related to surface flaking.

Selling, General and Administrative Expenses

The increase in selling, general and administrative expenses in 2016 compared to 2015 was attributable to a $2.2 million increase in personnel related expenses of salaries and benefits and incentive compensation due to improved performance against targets, $2.2 million increase in research and development expenses, and a $1.4 million increase in advertising and branding activities in support of our market growth strategies.

Provision for Income Taxes

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During 2016 and 2015, our income tax expense consisted of statutory federal and state taxes, permanent book to tax differences, federal tax credits, and other miscellaneous tax items. The effective tax rate in 2016 decreased 340 basis points compared to the effective tax rate during 2015 due to nondeductible compensation expense recognized in the prior year and the adoption of Financial Accounting Standards Board Accounting Standards Codification No. 2016-09, “Compensation – Stock Compensation (Topic718): Improvements to Employee Share-Based Payment Accounting.” As of January 1, 2016, the Company prospectively applied the guidance related to excess tax benefits and recorded a $1.7 million benefit within income tax expense. Excess tax benefits for 2015 were recorded as an increase to additional paid-in capital.

LIQUIDITY AND CAPITAL RESOURCES

We finance operations and growth primarily with cash flow from operations, borrowings, operating leases and normal trade credit terms from operating activities.

Sources and Uses of Cash. The following table summarizes our cash flows from operating, investing and financing activities for the years ended December 31, 2017, 2016, and 2015 (in thousands):

Operating Activities

Net cash provided by operating activities increased by $16.6 million in 2017 compared to 2016 primarily due to the $23.2 million, or 17.8%, increase in net sales during in 2017 coupled with the 4.1% increase in gross margin. The increase was primarily offset by the increase in accounts receivable at December 31, 2017 of $10.5 million.

Net cash provided by operating activities increased $22.7 million in 2016 compared to 2015 primarily due to higher cash receipts from the 8.8% increase in net sales during 2016 compared to 2015 coupled with the 390 basis point increase in gross margin, and a $4.4 million increase due to the timing of income tax payments.

Investing Activities

On July 31, 2017, through its newly-formed, wholly-owned subsidiary, Trex Commercial Products, the Company acquired certain assets and assumed certain liabilities of SC Company for $71.8 million in cash. The Company used cash on hand and $30 million of funding from its existing revolving credit facility to acquire the assets.

Additional investing activities consisted principally of capital expenditures directed to new product development and to quick return cost investments to capture manufacturing cost savings. These investments allow us to meet the market’s increased demand and corresponding volume requirements resulting in greater profitability and cash flow. Capital expenditures in 2017 were $15.0 million consisting primarily of $10.8 million for general plant cost reduction initiatives and $3.0 million for equipment and new product development.

Capital expenditures in 2016 were $14.6 million consisting primarily of $5.6 million for the purchase of, land adjacent to our Winchester, Virginia manufacturing facility, and Trex University (our state-of-the-art training facility), $5.6 million for investments to capture plant cost reduction initiatives, and $2.7 million for

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process and productivity improvement. Also, in January 2016, the Company sold a portion of the Olive Branch facility that contained the buildings for $4.2 million and, as of December 31, 2017, continues to own approximately 62 acres of undeveloped land adjacent to the sold properties.

Financing Activities

Net cash used in financing activities in 2017 decreased $59.2 million compared to 2016 primarily due to the $55.2 million in stock repurchase activity in 2016.

In January 2016, we increased our borrowing capacity in order to repurchase shares of our common stock and to support our seasonal working capital needs. Net cash used in financing activities was $62.4 million in 2016 compared to net cash used in financing activities of $42.9 million in 2015. The increase was primarily due to payments on outstanding debt balances earlier and at a higher level in 2016 compared to 2015 due to higher sales and reduced manufacturing costs.

Stock Repurchase Programs.

On October 23, 2014, our Board of Directors authorized a common stock repurchase program of up to 2.0 million shares of our outstanding common stock (October 2014 Stock Repurchase Program). This authorization had no expiration date. During the three months ended September 30, 2015, we repurchased 1,134,300 shares for $45.2 million under the October 2014 Stock Repurchase Program.

On October 22, 2015, our Board of Directors terminated the October 2014 Stock Repurchase Program and adopted a new stock repurchase program of up to 3.15 million shares of our outstanding common stock (October 2015 Stock Repurchase Program). In 2016, we repurchased 1,578,952 shares for $53.3 million under the October 2015 Stock Repurchase Program. This authorization terminated on December 31, 2016.

On February 16, 2017, the Board of Directors authorized a common stock repurchase program of up to 2.961 million shares of our outstanding common stock (February 2017 Stock Repurchase Program). The Company made no repurchases under the February 2017 Stock Repurchase Program. On February 16, 2018, the Board of Directors terminated the February 2017 Stock Repurchase Program and adopted a new stock repurchase program of up to 2.9 million shares of the Company’s outstanding common stock (February 2018 Stock Repurchase Program). As of the date of this report, the Company has made no repurchases under the February 2018 Stock Repurchase Program.

Inventory in Distribution Channels. We sell our residential decking and railing products through a tiered distribution system. We have over 50 distributors worldwide and two national retail merchandisers to which we sell our products. The distributors in turn sell the products to dealers and retail locations who in turn sell the products to end users. Significant increases in inventory levels in the distribution channel without a corresponding change in end-use demand could have an adverse effect on future sales. We cannot definitively determine the level of inventory in the distribution channels at any time. We are not aware of significant changes in the levels of inventory in the distribution channels at December 31, 2017 compared to inventory levels at December 31, 2016. On occasion, we may need to replace a distributor. Historically, we have had little difficulty replacing a distributor and have experienced little or no disruption to operations or liquidity. We believe that in the event we need to replace a distributor, it would not have an adverse effect on our profitability or liquidity.

Surface Flaking Warranty. We continue to receive and settle claims related to residential product produced at our Nevada facility prior to 2007 that exhibits surface flaking, which has had a material adverse effect on cash flow from operations, and regularly monitor the adequacy of the warranty reserve. During the year ended December 31, 2017, we paid approximately $5.7 million to settle surface flaking claims against the warranty reserve consistent with the $5.7 million paid in 2016. We estimate that the number of claims received will continue to decline over time and that the average cost per claim will increase slightly, primarily due to inflation.

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If the level of claims received or average settlement cost per claim differs materially from expectations it could result in additional increases or decreases to the warranty reserve and a decrease or increase in earnings and cash flows in future periods.

Business Acquisition. On July 31, 2017, through our wholly-owned subsidiary, Trex Commercial Products, Inc., we entered into a definitive agreement with SC Company and on that date acquired certain assets and liabilities of SC Company for $71.8 million in cash. We used cash on hand and $30.0 million from our existing revolving credit facility to acquire the business.

Seasonality. Our operating results have historically varied from quarter to quarter. Seasonal, erratic or prolonged adverse weather conditions in certain geographic regions reduce the level of home improvement and construction activity and can shift demand for our products to a later period. As part of our normal business practice and consistent with industry practice, we have historically offered incentive programs to our distributors and dealers to build inventory levels before the start of the prime deck-building season in order to ensure adequate availability of our product to meet anticipated seasonal consumer demand. The seasonal effects are often offset by the positive effect of the incentive programs.

Indebtedness. On January 12, 2016, the Company entered into a Third Amended and Restated Credit Agreement and also the First Amendment to the Third Amended and Restated Credit Agreement (together, the Third Amended Credit Agreement) with Bank of America, N.A. (BOA) as Lender, Administrative Agent, Swing Line Lender and Letter of Credit Issuer; and certain other lenders including Citibank, N.A., Capital One, N.A., and SunTrust Bank (collectively, Lenders) arranged by Bank of America Merrill Lynch as Sole Lead Arranger and Sole Bookrunner. The Third Amended Credit Agreement amended and restated the Second Amended Credit Agreement.

Under the Third Amended Credit Agreement, the Lenders agree to provide the Company with one or more revolving loans in a collective maximum principal amount of $250 million from January 1 through June 30 of each year and a maximum principal amount of $200 million from July 1 through December 31 of each year throughout the term, which ends January 12, 2021. Included within the revolving loan limit are sublimits for a letter of credit facility in an amount not to exceed $15 million and swing line loans in an aggregate principal amount at any time outstanding not to exceed $5 million. The revolving loans, the letter of credit facility and the swing line loans are for the purpose of funding working capital needs and supporting general business operations.

The Company has the option to select interest rates for each loan request at the Base Rate or Eurodollar Rate. Base rate loans under the revolving loans and the swing line loans accrue interest at the Base Rate plus the Applicable Rate. Eurodollar Rate Loans for the revolving loans and swing line loans accrue interest at the Adjusted London InterBank Offered Rate plus the Applicable Rate. The Base Rate for any day is a fluctuating rate per annum equal to the highest of (a) the Federal Funds Rate plus 0.50%, (b) the rate of interest in effect for such day as publicly announced from time to time by BOA as its prime rate, and (c) the Eurodollar Rate plus 1.0%.

Repayment of all then outstanding principal, interest, fees and costs is due on January 12, 2021.

The Company will reimburse BOA for all amounts payable, including interest, under a letter of credit at the earlier of (i) the date set forth in the application, or (ii) one business day after the payment under such letter of credit by BOA.

The Third Amended Credit Agreement is secured by property with respect to which liens in favor of the Administrative Agent, for the benefit of itself and the other holders of the obligations, are purported to be granted pursuant to and in accordance with the terms of the collateral documents as referenced in the Third Amended Credit Agreement.

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At December 31, 2017, the Company had no outstanding borrowings under the Third Amended Credit Agreement and $200 million of available borrowing capacity.

Compliance with Debt Covenants and Restrictions. Our ability to make scheduled principal and interest payments, borrow and repay amounts under any outstanding revolving credit facility and continue to comply with any loan covenants depends primarily on our ability to generate sufficient cash flow from operations. To remain in compliance with financial covenants, we are required to maintain specified financial ratios based on levels of debt, fixed charges, and earnings (excluding extraordinary gains and extraordinary non-cash losses) before interest, taxes, depreciation and amortization, all of which are subject to the risks of the business, some of which are discussed in this report under “Risk Factors.” We were in compliance with all covenants contained in the Third Amended Credit Agreement at December 31, 2017. Failure to comply with the financial covenants could be considered a default of our repayment obligations and, among other remedies, could accelerate payment of any amounts outstanding.

Contractual Obligations. The following tables show, as of December 31, 2017, our contractual obligations and commercial commitments, which consist primarily of purchase commitments and operating leases (in thousands):

Contractual Obligations

Payments Due by Period

Off-Balance Sheet Arrangements. We do not have off-balance sheet financing arrangements other than operating leases.

Capital and Other Cash Requirements. We currently estimate that capital expenditures in 2018 will be approximately $20 million to $25 million. Our capital allocation priorities include expenditures for internal growth opportunities, manufacturing cost reductions, acquisitions which fit our long-term outdoor products growth strategy as we continue to evaluate opportunities that would be a good strategic fit for Trex, and return of capital to shareholders.

We believe that cash on hand, cash flows from operations and borrowings expected to be available under our revolving credit facility will provide sufficient funds to enable us to fund planned capital expenditures, make scheduled principal and interest payments, fund the warranty reserve, meet other cash requirements and maintain compliance with terms of our debt agreements for at least the next 12 months. We currently expect to fund future capital expenditures from operations and borrowings under the revolving credit facility. The actual amount and timing of future capital requirements may differ materially from our estimate depending on the demand for Trex and new market developments and opportunities. Our ability to meet our cash needs during the next 12 months and thereafter could be adversely affected by various circumstances, including increases in raw materials and product replacement costs, quality control problems, higher than expected product warranty claims, service disruptions and lower than expected collections of accounts receivable. In addition, any failure to negotiate amendments to our existing debt agreements to resolve any future noncompliance with financial covenants could

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adversely affect our liquidity by reducing access to revolving credit borrowings needed primarily to fund seasonal borrowing needs. We may determine that it is necessary or desirable to obtain financing through bank borrowings or the issuance of debt or equity securities to address such contingencies or changes to our business plan. Debt financing would increase our level of indebtedness, while equity financing would dilute the ownership of our stockholders. There can be no assurance as to whether, or as to the terms on which, we would be able to obtain such financing, which would be restricted by covenants contained in our existing debt agreements.

NEW ACCOUNTING STANDARDS

In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 606),” and issued subsequent amendments to the initial guidance in August 2015 within ASU No. 2015-14, in March 2016 within ASU No. 2016-08, in April 2016 within ASU No. 2016-10, in May 2016 within ASU No. 2016-12, and in December 2016 within ASU No. 2016-20 (collectively, the new standard). The new standard provides a single, comprehensive model for revenue arising from contracts with customers and supersedes most current revenue recognition guidance. The new standard requires an entity to recognize revenue when it satisfies a performance obligation at an amount that reflects the consideration to which the entity expects to be entitled in exchange for transferring control of goods or services to a customer. The Company will adopt the new standard in the first quarter of fiscal 2018. The Company intends to use the retrospective application to each reporting period presented, with the option to elect certain practical expedients as defined in the new standard. The Company has completed its evaluation of its Trex Residential segment and determined that adoption of the new standard will not have a significant impact on that segment. The Company continues to evaluate the impacts of adoption on its Trex Commercial segment, which was acquired on July 30, 2017. The Company expects expanded financial statement note disclosure.

In February 2016, the FASB issued ASU No. 2016-02, “Leases (Topic 842).” The new standard requires lessees to recognize leases on the balance sheet as a right-of-use asset and a lease liability, other than leases that meet the definition of a short-term lease. The liability will be equal to the present value of the lease payments. The asset will be based on the liability, subject to adjustment. For income statement purposes, the leases will continue to be classified as either operating or finance. Operating leases will result in straight-line expense (similar to current operating leases) and finance leases will result in a front-loaded expense pattern (similar to current capital leases). The standard is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. Early adoption is permitted. The new standard must be adopted using the modified retrospective transition method and provides for the option to elect a package of practical expedients upon adoption. The Company is currently assessing the impact of adoption of the new standard on its consolidated financial statements and related note disclosures and has not made any decision on the option to elect adoption of the practical expedients.

In August 2016, the FASB issued ASU No. 2016-15, “Statement of Cash flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments.” The guidance is intended to reduce diversity in practice across all industries in how certain transactions are classified in the statement of cash flows. The standard is effective for financial statements issued for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. Early adoption is permitted. The guidance requires application using a retrospective transition method. The Company is assessing the impact of adoption of the new standard on its consolidated financial statements and related note disclosures.

We are subject to market risks from changing interest rates associated with our borrowings. To meet our seasonal working capital needs, we borrow periodically on our variable rate revolving line of credit. At December 31, 2017, we had no debt outstanding under our revolving line of credit. While variable rate debt obligations expose us to the risk of rising interest rates, an increase of 1% in interest rates would not have a material adverse effect on our overall financial position, results of operations or liquidity.

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In certain instances we may use interest rate swap agreements to modify fixed rate obligations to variable rate obligations, thereby adjusting the interest rates to current market rates and ensuring that the debt instruments are always reflected at fair value. We had no interest rate swap agreements outstanding as of December 31, 2017.

The financial statements listed in Item 15 and appearing on pages F-2 through F-30 are incorporated by reference in this Item 8 and are filed as part of this report.

None.

Evaluation of Disclosure Controls and Procedures

The Company’s management, with the participation of its President and Chief Executive Officer, who is the Company’s principal executive officer, and its Vice President and Chief Financial Officer, who is the Company’s principal financial officer, has evaluated the effectiveness of the Company’s disclosure controls and procedures as of December 31, 2017. We have excluded Trex Commercial Products, Inc., our wholly-owned subsidiary which is included in our Consolidated Financial Statements, from our assessment of internal control over financial reporting as of December 31, 2017, because it was formed to acquire certain assets and assume certain liabilities of Staging Concepts Acquisition, LLC and Stadium Consolidation, LLC in a business combination on July 31, 2017. Based on this evaluation, the President and Chief Executive Officer and the Vice President and Chief Financial Officer have concluded that the Company’s disclosure controls and procedures are effective.

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

Retirement of Frank H. Merlotti, Jr.

On February 16, 2018, Frank H. Merlotti, Jr., whose current term of service on the Company’s Board of Directors (Board) expires on the date of the Company’s annual meeting of stockholders on May 2, 2018, informed the Board of his decision not to stand for re-election. Mr. Merlotti serves on the Board’s Compensation Committee and Nominating / Corporate Governance Committee.

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Management’s Report on Internal Control Over Financial Reporting

We, as members of management of Trex Company, Inc. (the “Company”), are responsible for establishing and maintaining adequate internal control over financial reporting. The Company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. Internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the Company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the Company are being made only in accordance with authorizations of management and directors of the Company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the Company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies and procedures may deteriorate.

We assessed the Company’s internal control over financial reporting as of December 31, 2017, based on criteria for effective internal control over financial reporting established in “Internal Control-Integrated Framework (2013)” issued by the Committee of Sponsoring Organizations of the Treadway Commission (the “COSO Framework”). We have excluded Trex Commercial Products, Inc. (Trex Commercial), our wholly-owned subsidiary which is included in our Consolidated Financial Statements, from our assessment of internal control over financial reporting as of December 31, 2017, because it was formed to acquire certain assets and assume certain liabilities of Staging Concepts Acquisition, LLC and Stadium Consolidation, LLC in a business combination on July 31, 2017. Total assets and net sales of Trex Commercial as of and for the year ended December 31, 2017, were 24% and 4%, respectively, of the Company’s total assets and net sales. Based on this assessment, we concluded that, as of December 31, 2017, our internal control over financial reporting was effective, based on the COSO Framework.

The effectiveness of our internal control over financial reporting as of December 31, 2017, has been audited by Ernst & Young LLP, an independent registered public accounting firm, as stated in their report, which follows hereafter.

Changes in Internal Control Over Financial Reporting

There have been no changes in the Company’s internal control over financial reporting identified in connection with the evaluation described above in “Management’s Report on Internal Control Over Financial Reporting” that occurred during the Company’s fourth fiscal quarter that have materially affected, or are reasonably likely to materially affect, the Company’s internal control over financial reporting.

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Report of Independent Registered Public Accounting Firm

To the Stockholders and the Board of Directors of Trex Company, Inc.

Opinion on Internal Control over Financial Reporting

We have audited Trex Company, Inc.’s internal control over financial reporting as of December 31, 2017, based on criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework) (the COSO criteria). In our opinion, Trex Company, Inc., (the Company) maintained, in all material respects, effective internal control over financial reporting as of December 31, 2017, based on the COSO criteria.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated balance sheets of the Company as of December 31, 2017 and 2016, and the related consolidated statements of comprehensive income, stockholders’ equity and cash flows for each of the three years in the period ended December 31, 2017, and the related notes and schedule and our report dated February 21, 2018 expressed an unqualified opinion thereon.

As indicated in the accompanying Management’s Report on Internal Control over Financial Reporting, management’s assessment of and conclusion on the effectiveness of internal control over financial reporting did not include the internal controls of Trex Commercial Products, Inc., which is included in the 2017 consolidated financial statements of the Company and constituted 24% and 30% of total and net assets, respectively, as of December 31, 2017 and 4% and (2)% of net sales and net income, respectively, for the year then ended. Our audit of internal control over financial reporting of the Company also did not include an evaluation of the internal control over financial reporting of Trex Commercial Products, Inc.

Basis for Opinion

The Company’s management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting included in the accompanying Management’s Report on Internal Control over Financial Reporting. Our responsibility is to express an opinion on the Company’s internal control over financial reporting based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects.

Our audit included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, testing and evaluating the design and operating effectiveness of internal control based on the assessed risk, and performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

Definitions and Limitations of Internal Control Over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable

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assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

/s/ Ernst & Young LLP

Richmond, Virginia

February 21, 2018

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PART III

Information responsive to this Item 10 is incorporated herein by reference to our definitive proxy statement for our 2018 annual meeting of stockholders, which we will file with the SEC on or before 120 days after our 2017 fiscal year-end.

We have adopted a code of conduct and ethics, which is applicable to all of our directors, officers and employees, including our Chief Executive Officer and Chief Financial Officer. The code is available on our corporate web site and in print to any stockholder who requests a copy. We also make available on our web site, at www.trex.com, and in print to any stockholder who requests them, copies of our corporate governance principles and the charters of each standing committee of our board of directors. Requests for copies of these documents should be directed to Corporate Secretary, Trex Company, Inc., 160 Exeter Drive, Winchester, Virginia 22603-8605. 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 web site 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.

Information responsive to this Item 11 is incorporated herein by reference to our definitive proxy statement for our 2018 annual meeting of stockholders, which we will file with the SEC on or before 120 days after our 2017 fiscal year-end.

Information responsive to this Item 12 is incorporated herein by reference to our definitive proxy statement for our 2018 annual meeting of stockholders, which we will file with the SEC on or before 120 days after our 2017 fiscal year-end.

Information responsive to this Item 13 is incorporated herein by reference to our definitive proxy statement for our 2018 annual meeting of stockholders, which we will file with the SEC on or before 120 days after our 2017 fiscal year-end.

Information responsive to this Item 14 is incorporated herein by reference to our definitive proxy statement for our 2018 annual meeting of stockholders, which we will file with the SEC on or before 120 days after our 2017 fiscal year-end.

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PART IV

(a)(1) The following Consolidated Financial Statements of the Company appear on pages F-2 through F-30 of this report and are incorporated by reference in Part II, Item 8:

(a)(2) The following financial statement schedule is filed as part of this report:

All other schedules for which provision is made in the applicable accounting regulations of the SEC are not required under the related instructions or are inapplicable or not material and, therefore, have been omitted.

(a)(3) The following exhibits are either filed with this Form 10-K or are incorporated herein by reference. The Company’s Securities Exchange Act file number is 001-14649.

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TREX COMPANY, INC.

Index to Consolidated Financial Statements

The following Consolidated Financial Statement Schedule of the Registrant is filed as part of this Report as required to be included in Item 15(a)(2):

F-1

Report of Independent Registered Public Accounting Firm

To the Stockholders and the Board of Directors of Trex Company, Inc.

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of Trex Company, Inc. (the Company) as of December 31, 2017 and 2016, the related consolidated statements of comprehensive income, stockholders’ equity and cash flows for each of the three years in the period ended December 31, 2017, and the related notes and financial statement schedule listed in the Index at Item 15(a)(2) (collectively referred to as the “consolidated financial statements”). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company at December 31, 2017 and 2016, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2017, in conformity with U.S. generally accepted accounting principles.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company’s internal control over financial reporting as of December 31, 2017, based on criteria established in Internal Control-Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework) and our report dated February 21, 2018 expressed an unqualified opinion thereon.

Basis for Opinion

These financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on the Company’s financial statements based on our audits. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

/s/ Ernst & Young LLP

We have served as the Company’s auditor since 1995.

Richmond, Virginia

February 21, 2018

F-2

TREX COMPANY, INC.

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

See Notes to Consolidated Financial Statements.

F-3

TREX COMPANY, INC.

CONSOLIDATED BALANCE SHEETS

See Notes to Consolidated Financial Statements.

F-4

TREX COMPANY, INC.

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY

(In thousands, except share data)

See Notes to Consolidated Financial Statements.

F-5

TREX COMPANY, INC.

CONSOLIDATED STATEMENTS OF CASH FLOWS