Composite decking has only been around for a few decades, but it’s a compelling option to consider for your deck.
Composite decking has only been around for a few decades, but it’s a compelling option to consider for your deck. Most forms of composite decking are made from a blend of post-consumer plastic waste and wood pulp or non-wood fibers. The plastic component—polyethylene or polypropylene—makes the material impervious to rotting, and insects don’t like it. Unlike solid wood, it has no grain, so it won’t splinter or crack, and there are no knots or natural defects to cut away. Other formulations of synthetic decking contain no wood at all. These are made from polyethylene, PVC, polystyrene or fiberglass blends. Composite decking comes with impressive warranties, which may last from 10 years to a lifetime, depending on the product. Some warranties are transferable from one homeowner to the next.
When composite lumber first hit the market, it didn’t look anything like wood, and color choices were limited. Now, it’s available in a range of wood textures and colors. Most products are non-toxic; easy to cut, drill, and fasten; and do not require finishing. Maintenance is usually limited to an occasional cleaning or spot removal. However, composite decking is more flexible than wood, so you may need to use closer joist spacing in your deck design. It’s also heavier than wood and considerably more expensive.
Composite materials blend together wood fibers and recycled plastics to create a rigid product that, unlike wood, will not rot, splinter, warp, or crack. Painting or staining is unnecessary. Like wood, these deck boards can be cut to size, using a circular saw with a large tooth blade.
PVC vinyl and plastic decking materials are shipped in kits that contain everything necessary to install the decking other than the deck screws. The kits are preordered to size, usually in multiples of the combined width of a deck board and the fasteners. The drawback of PVC vinyl decking is that it expands and contracts with freeze/thaw cycles.
Fiberglass reinforced plastic (FRP) decking will last a lifetime. Manufacturers claim that the material is three times as strong as wood and not affected by heat, -sunlight, or severe weather. The decking is preordered to size but if necessary, it can be cut using a circular saw with a diamond-tip blade or masonry blade.
Surface patterns for composite decking range from virtually no pattern to straight or cathedral wood grain styles. Pattern options will vary by product and manufacturer. Some simulated wood grains are quite convincing!
Composite decking colors cover the spectrum of wood tones, plus grays and white. The color is continuous throughout the material, but full exposure to sunlight may cause the surface color to fade.
While composite decking can be fastened down conventionally with screws, you may be able to use various edge-fastening systems instead to avoid driving screws through the board faces.
Composite and other nonwood decking often requires special fasteners that are designed to reduce “mushrooming” that occurs when the decking material bulges up around the screwhead. Pilot holes are recommended for some types as well.