Solid boards generally have better fastener

Hollow profiles also may be less impact resistant and more susceptible to yard or jobsite damage. Solid boards generally have better fastener holding power. Bill Ross, v.p. of sales & marketing for Fiber Composites, says solid decking's greater mass permits it to hold more additives needed to protect the plastic molecules in each board. Solid composite decking
"Solid profiles are more readily accepted by deck builders and building professionals because it's a more traditional profile," Ross says. "Solid boards also are easier to work with; they require a minimal learning curve. Solid profiles do not need special end treatments, plugs, picture framing, etc., to hide the hollow cavities."
Whether solid or voided makes for a stronger board is up for debate. GAF/Elk maintains that specially-engineered arched voids in its CrossTimbers decking result not only in a board that is 30% lighter, but also stronger and stiffer than many solid boards. Instead of polyethylene, they use polypropylene to achieve a greater strength-to-weight ratio, eliminating bounce or sag, so boards feel more solid under foot.
Also known as wood-plastic composites, composite decking is made from recycled wood and plastic as an environmentally friendly option that is growing in popularity. Advantages like durability, color retention and reduced maintenance have increased the replacement of natural wood. Composite decking doesn't require painting and staining. The only maintenance that needs to be done to composite decks is to wash it about two to three times a year to avoid mildew and mold build-up. Composite decking cost about 20 - 30 percent more than pre-treated pinewood, but in the long run, it pays off as you eliminate the yearly maintenance of staining, weathering, and the need to replace rotting or splitting boards. Solid Decking board
In addition to being environmentally friendly because of its use of recycled wood fibers and plastics, composite decking doesn't contain wood preservatives. This avoids the issues of arsenic and other heavy metals found in pressure-treated wood. Without any wood preservatives, composite decks are resistant to decay fungi and insects.
There are two types of composite decks available: solid and hollow. Solid profile decking emulates the shape of real wood lumber but also has more expansion and contraction properties because of its mass. Hollow profile decking has an engineered look and less mass than its counterpart. It possesses lower expansion and contraction properties, but is more susceptible to yard or job site damage.
Composite decking is not a perfect system. Composite decks tend to weather by 10 percent within a three-month period, which is normal considering that composite decks have wood fibers. So when choosing a composite deck, make sure to look at decks that have been exposed to the sun for at least a year to determine if you like the appearance. Because composite decking is weaker than wood, it still needs to be held up by treated wood joist and beams to avoid sagging or drooping.
Having a new deck is a large investment to a home. It is a good idea to do the research into composite decking. Read brochures from various manufactures, check out specifications to each composite by looking at their strength, expansion, water absorption, durability, and density. As a homeowner, you want composite decking to be what you pay for, low-maintenance, environmentally friendly, of good quality, fade resistant, and doesn't warp or splinter. Manufactures of composite decking claim that the number one reason why a deck will bend or will need replacing is because directions are not followed.
Contractors should just be sure that, from a strength perspective, they check to see how the decking is rated, to ensure correct spacing of joists. TimberTech offers both a traditional solid 5/4 profile and a hollow profile-Floorizon-which it developed over 10 years ago to replace then-popular 2x6 decking. "It requires less framing and in many cases could be used on a deck with 24" on center joist spacing due to its 1-1/2" height," said Tom Day, senior product manager. "It was designed using a hidden fastener system for a clean look when finished, a unique TimberTech feature at the time that is taken for granted today." Composite Decking Manufacturer