Capped Wood-Plastic Composites (WPC)

The Industry Standard (Brands like Trex & Fiberon)

Capped Composite decking is manufactured by creating a core mixture out of recycled wood sawdust (wood flour) and recycled polyethylene plastic (usually from shopping bags and shrink wrap). Because the inner core contains organic wood fibers, these boards were traditionally susceptible to swelling if moisture penetrated them, which is why modern versions are "capped."

During the manufacturing extrusion process, a pure plastic exterior shell (the "cap") is co-extruded around the wood-plastic core. This cap provides the gorgeous faux-wood grain texture, the UV fade resistance, and a completely waterproof barrier. Capped composites represent the best balance of price and performance, typically ranging from $60 to $100 per installed square foot.

Cellular PVC Decking

The Ultra-Premium Maritime Upgrade (Brands like TimberTech Advanced PVC / Azek)

PVC decking contains absolutely zero organic wood fiber. It is a 100% synthetic polymer board through and through. Because it has no wood mass to absorb water, PVC is the absolute mandatory choice for docks, boathouses, or decks completely surrounding heavy-splash swimming pools where boards are subjected to constant submerged conditions.

Furthermore, because PVC lacks heavy, dense wood fibers in its core, the boards dissipate heat much faster than dense Wood-Plastic Composites. A PVC deck will remain significantly cooler to the touch in direct afternoon sunlight—a major selling point for families with bare feet and pets. The tradeoff is price: PVC is the most expensive decking category on the market, frequently capping $90 to $130 per installed square foot.