There are several options for decking material, with four factors that affect your choice: durability, availability, looks, and cost.
Redwood. This is a popular, naturally rot-resistant wood. With a clear sealer applied biannually, redwood will last a long time. It is easy to find on the West Coast and at large home improvement centers elsewhere. The reddish hue is not suited to the look of every home. It is the most expensive decking material, so consider using another wood for the framing and redwood for decking.
Cedar. This rot-resistant wood is strong and durable. It is more common in the South and on the West Coast. Cedar weathers silvery gray unless you apply a sealer. It costs about 20 percent less than redwood, depending on availability.
Cypress. Another rot-resistant wood, cypress is most popular in the Southeast. It is not as strong as cedar, redwood, or pressure-treated wood. Consider using a pressure-treated wood for the frame and cypress for decking. It costs a little less than cedar in the South and a little more everywhere else.
Pressure-treated lumber. This is the strongest and most readily available lumber. Most comes with a greenish cast that weathers to a silvery gray, but you can also get it prestained to look like cedar or redwood. Treated lumber is the most affordable deck material, and thanks to new laws restricting the chemicals used to preserve the wood, today's treated lumber is safe.
Synthetic Decking. If low maintenance is your key concern, consider synthetic materials. Plastic lumber, which is made of recycled milk jugs and grocery bags, does not absorb moisture. Molded in various colors, plastic lumber can be painted, but it will never quite take on the look of wood. For proper installation, you need to use sliding clips because plastic expands and contracts in temperature extremes.
Vinyl lumber comes in white and several additional colors. Its pros and cons are similar to plastic lumber. Purchase brands that have the UV inhibitors impregnated directly into the vinyl and not sprayed on after production.
Wood-polymer lumbers are another option. They contain up to a 50-50 ratio of waste wood and recycled plastics and can be stained or painted. These products look and feel like wood but never require maintenance.
Regardless of which type of synthetic material you choose, you will need to install it over a support system built using real wood. To keep costs down, most homeowners choose treated lumber for these invisible underpinnings.