Trex Board Sizes Explained: Width, Thickness & Length

Before you order Trex decking, it helps to understand how the boards are actually sized - because composite decking doesn't follow the same nominal dimensions as lumber, and getting it wrong means wasted material or boards that don't install correctly.

The Basics That Apply to Every Trex Collection

All Trex decking boards - Signature, Transcend Lineage, Transcend, Select, and Enhance - share a standard actual width of 5.5 inches. That consistency makes planning straightforward regardless of which collection you choose.

Where they differ is thickness. Signature, Lineage, Transcend, and Enhance boards measure 0.94 inches thick, giving them a solid, substantial feel underfoot. Select comes in slightly thinner at 0.82 inches, which makes the boards lighter and easier to handle - a practical advantage for DIY installs or large orders.

Length Options and Why They Matter

Trex boards are available in 12, 16, and 20-foot lengths. Longer boards mean fewer seams across the deck surface and a cleaner finished look. Shorter boards are easier to transport and work better for stairs, benches, and tighter sections. Most builds use a mix of both.

Grooved vs. Square Edge

Grooved-edge boards are designed for hidden fastener systems - no exposed screw heads, cleaner surface finish. Square-edge boards are face-screwed and are typically used for picture framing and perimeter borders. Both profiles share the same 5.5-inch width, so they work together in the same build.

Fascia and 2-Inch Boards

Trex fascia boards in 1x8 and 1x12 profiles finish the exposed edges and stair risers. For structural applications like stairs and picture frames, Trex also offers thicker 2-inch boards in 2x4 and 2x6 sizes.

Read the full "Trex Deck Board Dimensions: A Complete Size Guide" here!