A deck provides a comfortable outdoor space where you can drink morning coffee, admire local vistas and throw a party with friends. It can also add value to your home if you build one where none existed before. The price per square foot to construct a deck depends on the materials and your home's location.
With prices accurate at the time of publication, "Remodeling Magazine" states that a basic deck addition of wood averages about $10,973, including installation. This is for a 16-by-20-foot version that includes pressure-treated joists, supported by 4-inch-square posts buried in concrete piers. The boards are laid out in a simple pattern and support a built-in bench, planter and a stair of three steps out of the same material. The deck is also surrounded by a rail with pressure-treated wood posts and balusters. The price per square foot of this addition is almost $34.20 and is expected to fetch $7,986 in resale costs, which is close to a 73 percent return on investment.
Because the deck is made out of pressure-treated wood, it requires staining every so often to protect it from deterioration. The first of these treatments must occur at least six months after building, to allow the chemicals in the treated wood to dry out. If you're willing to do the fairly simple work yourself, it will only cost $50 to $100 for enough stain to cover 500 square feet. That breaks down to between $0.10 and $0.20 a square foot. If you'd prefer to hire someone to do it for you, expect to spend about $0.50 per square foot additional, or $250 per 500 square feet. This information comes from "Cost Owl" and is current as of October, 2011.
Composite decking can imitate the appearance and color of wood but requires no staining or maintenance beyond washing because of its synthetic composition. "Cost Owl" states that building a composite deck, with the same characteristics as a basic wood deck, costs $15,620 or about $48.81 per square foot. Although this price is initially higher than a wood construct, it saves money in the long run in the cost and time required for staining. Composite decks bring in a lower rate of return, however, at 66 percent or $10,337.
"Cost Owl" estimates the average cost of a premium composite deck at $38,382 or $57.60 per square foot. This is for a 16-by-20-foot (320 square feet) structure supported by 4-inch square posts buried in concrete pier, with a 10-foot-diameter, six-sided platform (346 square feet) in one corner that is a step down from the main deck. This includes a bench and planter, a three-step stair and a railing system with balusters, post caps and lighting. The boards use a simple linear pattern, and all additions are constructed of the same composite decking material. Because of its initial cost, a premium deck brings in only about 58 percent during resale, which equals $22,154.