State Roofing

Roofing and Decking
Founded in 1968
Over 50,000 projects installed

Trex Decking Frequently Asked Questions

General Information

What is Trex decking?
Trex Wood-Polymer® lumber is made from reclaimed plastic and wood waste in approximately equal proportions. Its durability makes it an ideal choice for decking and landscaping.

What colors does Trex come in?
Information on our colors can be found on our Colors and Sizes page and our Weathering Page.

Is Trex decking made of recycled materials?
Trex decking is made from post-consumer and/or post-industrial reclaimed plastic and waste wood. The reclaimed plastic comes primarily from grocery sacks and stretch film, and the waste wood is from woodworking manufacturers.

What is the difference between Trex decking and "plastic lumber?"
Unlike plastic lumber, which is typically 100% plastic, Trex decking is approximately 50% wood fiber and 50% plastic. Because of the wood content, Trex decking has the advantages of low thermal expansion/contraction, natural UV stability, good traction and paintability, and Trex decking is just as easy to work with as wood.

What sizes and lengths does Trex Wood-Polymer lumber come in?
Trex Wood-Polymer lumber is available in popular lumber dimensions. Standard items include 1x6, 5/4x6, 2x2 (balusters), 2x4, 2x6 and 2x8. Standard lengths are 12', with 5/4x6, 2x4 and 2x6 available in 16' lengths. 5/4x6 and 2x6 are also available in 20' lengths. Custom profiles are also available and include 2x10, 3x6, and 4x6. See the Trex Sizes and Colors page for details on our other profiles.

Will the color of Trex decking change?
Trex decking will change color slightly after 6-12 weeks exposure to the sunlight and water. Please see our Weathering page for more information.

Does Trex decking come with a warranty?
Yes, Trex decking has a fully-transferable limited warranty unmatched by competitive materials. The Trex decking limited warranty offers coverage against material defects in workmanship and materials, and against splintering, splitting, checking, rot, decay and termite damage, for a full 10 years. The total life expectancy for Trex decking is currently undetermined. Accelerated age testing is ongoing and to date we know of no environmental factors that harm or cause significant deterioration to Trex decking. See warranty details.

How do I dispose of Trex decking? Can it be taken to a landfill?
Trex lumber contains no toxic preservatives and can be included and disposed of with normal construction debris.

Where can you buy Trex decking and how much does it cost?
Trex decking is available nationwide through a network of approximately 2500 lumber dealers. You can call 1-800-BUY-TREX for the dealer nearest you. You'll find that Trex decking is very competitive in cost to premium grades of decking lumbers. And, since Trex decking never requires stains or sealants for protection, you will be dollars ahead after only a few years.

Working with Trex Decking

Do I need special tools to work with Trex decking?
Trex Wood-Polymer lumber is just as easy to work with as wood, in some ways even easier. It can be cut, drilled, routed and nailed using standard tools. Carbide blades are recommended for best performance.

What types of fasteners are recommended for Trex decking? Do screws need to be pre-drilled?
Virtually any deck fasteners work well with Trex decking. We recommend high quality screws or nails, such as stainless steel, ceramic coated or hot dipped galvanized to take advantage of Trex decking's longevity. As with wood, spiral shank nails provide better holding in Trex decking than do common nails. Pre-drilling is generally not required if you use self-tapping or deck screws. Nail guns also work quite well.

Can Trex lumber be used for deck posts or joists?
No. While Trex lumber is tough and durable, it does not have the same stiffness as wood. Therefore, it is not intended for use as a load bearing post, joist or any other primary load-bearing member.

What joist spans should I use for my deck when using Trex decking?
For Trex 5/4x6 deck boards, the joist spacing should be no more than 16" on center for residential applications, which is the same span generally recommended for wood. Trex 2x material should be installed at no more than 20" on center for residential applications and no more than 16" on center for commercial projects. When installing Trex deck boards on a 45 degree diagonal to the joists, reduce spans by a minimum of 4 inches. Special applications/loading conditions will require engineering analysis and/or reduced spans.

Does Trex decking require gapping between boards?
Yes, in both directions. While Trex decking will not noticeably shrink or swell due to changes in moisture, changes in temperature will cause slight expansion/contraction. Therefore, gapping is required both side-to-side and at the end joints to allow for thermal expansion/contraction. Rules of Thumb: For end joints for 16' boards and smaller, allow a minimum of 1/16" gap for every 20┬░F of difference between installation temperature and the hottest temperature expected. For width-to-width gap required is 1/4". For cold weather installations, 3/8" is recommended.

Can Trex decking be painted or stained?
Trex decking readily accepts paint or stain though neither is required for protection. In general, paints or stains which adhere well to wood will adhere as well or better to Trex decking. Quality latex paints (water based) or solid color stains are recommended. Stain and paint applications should be applied according to the manufacturers instructions after the Trex decking fading process is complete.

What do I need to do to care for my Trex deck?
Trex decking does not require stains or sealants for protection. All you need to do to your Trex deck is to clean it periodically.

How do you clean stains on Trex decking?
For stains caused by mold, mildew, berries and leaves, conventional deck washes containing sodium hypochlorite work well. For rust stains, ground-in dirt and grime, use cleaners containing phosphoric acid. For grease and oil stains, we recommend that you scrub with a detergent containing a degreasing agent as soon as the stain occurs. Cleaning out your expansion gaps with a flat tool should be done along with any periodic cleaning.

How do you bend Trex?
You can find information about this on our Bending page. Other information similar to this can be found in our Architect's Binder links.

Product Characteristics

How should Trex Wood-Polymer lumber be handled?
Trex decking weighs more than wood and is more flexible. Do not attempt to lift similar volumes of Trex decking as you do wood. When storing Trex decking at the job site for extended periods, be sure to keep the material flat.

Will Trex decking absorb moisture?
Because of the plastic in Trex decking that surrounds the wood fiber, moisture absorption is extremely low.

Does Trex decking provide good traction?
Trex decking provides a stable, firm, slip-resistant surface - wet or dry (ASTM D 2047 and ASTM F1679 ).

What happens to Trex decking in cold weather?
Trex decking performs well in extreme cold weather environments. However, because Trex decking is 50% plastic, it will be harder to nail when very cold. Under these conditions, pre-drilling is recommended.

What happens to Trex decking in hot weather?
The span charts and gapping procedures are designed to ensure that Trex decking performs well in extreme hot weather. When the temperature increases, Trex decking will become more flexible, and it will expand/contract slightly. For this reason, the span tables and gapping instructions should be closely followed.

Can Trex Wood-Polymer lumber be used in full ground contact? Is treating required?
Trex lumber is ideal for ground contact applications such as landscaping timbers, walkways and in-ground pool surrounds. Trex decking is highly resistant to rot and insects, and absolutely no treating is required.

Will insects damage Trex decking?
Trex decking has been tested and found to be highly resistant to damage from termites, carpenter ants and marine borers.

What is the fire rating for Trex products?
Trex decking and railing is rated as a Class C (or Class III) building material. It burns similarly to wood. In combustion property testing, Trex products were found to be no more toxic than wood.

How does the weight of Trex Wood-Polymer lumber compare to lumber?
Because of its density, Trex Wood-Polymer lumber is comparable in weight to hardwoods. In comparison to softwoods such as redwood, cedar and treated southern pine, Trex products can weigh up to twice as much.

Do building inspectors approve Trex decking and railing?
Trex products have been approved for use in residential and commercial installations throughout North America. Trex decking has received a listing with ICBO (Report ICBO ES ER-5747) and the National Evaluation Service (Report NER-508) which covers BOCA and SBCCI.