Top 5 Decking Options
Updated: May 10, 2018
If you’re thinking about either building a new wood deck or remodeling an existing deck, then you may have noticed your choice in decking boards has grown exponentially over the past several years. It wasn’t long ago when the only choice was wood, which came in perhaps two or three species. However, thanks to an explosion of composite lumber, plastic decking, and hardwood imports, there’s now a dizzying array of decking choices available. Here’s a detailed look at the five most popular types:
1 Pressure-treated lumber—Despite all the competition, this ubiquitous green-tinted wood is still the number one decking material sold today. In fact, according to Arch Treatment Technologies, a leading producer of wood preservatives, approximately 75% of all new decks are finished with pressure-treated (PT) decking.
The widespread popularity of PT lumber isn’t surprising: it’s affordable, readily available coast-to-coast, and easy to cut and fasten with nails or screws. Most PT decking is milled from southern yellow pine, and then chemically treated to resist rot, fungus and wood-boring bugs. The two most common sizes of treated decking are 2x6s (90 cents per lin. ft.), and 5/4 x 6-in. planks ($1). Occasionally 2x4s (60 cents) are used, but typically only on small decks.
The downside of PT lumber is that it’s not very dimensionally stable, so it has a tendency to crack, split and warp. And routine maintenance is necessary to prolong the life and look of the deck. This includes an annual power washing, and application of stain or wood preservative every two or three years.
By the way, for more than 70 years PT lumber was infused with chromated copper arsenate (CCA), a suspected—some say, known—carcinogen. However, CCA hasn’t been used in residential lumber since December 2003. Today’s PT lumber is treated with safer, less-toxic chemicals, such as alkaline copper quaternary (ACQ) or copper azole. A newer carbon-based, non-metallic preservative is also available in a limited number of products, including Wolmanized L3 Outdoor Wood.
2 Redwood and cedar—For many purists, the only choice for decking is either redwood or red cedar. Both of these western softwoods are prized for their rich color and natural beauty, and for the fact that they aren’t pumped full of chemicals or preservatives. Both species contain tannins and oils that make them naturally resistant to rot, decay and voracious insects.
However, the level of weather- and bug-resistance is directly related to the amount of heartwood in the boards. Heartwood grows closer to the center of the tree, and is relatively hard and very decay resistant. Sapwood grows in the outer part of the tree, nearer the bark, and is softer and more susceptible to decay.
The California Redwood Association (CRA) recommends using sapwood-streaked Construction Common or Deck Common redwood for decking, but many pro deck builders prefer to use B-grade redwood, which is nearly clear of knots and contains mostly heartwood. For decking that’s 100% heartwood, the CRA suggests using Construction Heart redwood.
According to the experts at the Western Red Cedar Lumber Association, the four best grades of cedar to use for decking are (listed from most expensive/clearest, to least expensive/most knotty): Architect Clear, Custom Clear, Architect Knotty, and Custom Knotty.
In most regions of the country, redwood and cedar each cost at least three times more than pressure-treated lumber. For example, I recently bought an 8-ft.-long red cedar 2x6 and paid nearly $4 per lin. ft.—ouch! Both species are considerably less expensive on the west coast. In California, for instance, a B-grade redwood 2x6 costs about $2.35 per lin. ft.
Redwood and cedar require an annual power washing and coat of finish every three to four years. To protect the wood’s surface from the weather, and to help reduce checking (fine splits), apply a clear, water-repellant wood preservative. However, to maintain the wood’s natural color, you’ll have to apply a stain. If you don’t, both redwood and cedar will eventually weather to a soft silvery gray.
3 Tropical hardwoods—Massaranduba, cumaru, red tauari, tigerwood, ipe, and Phillipine mahogany are just some of the tropical hardwoods available for decking. These exotic, rich-grained woods are extremely hard, very durable and naturally resistant to rot and insects.
However, because these woods are so dense, they’re extremely heavy and very hard to cut and drill. In fact, it’s virtually impossible to drive a nail or screw without first boring a pilot hole, which is why tropical decking is typically installed with some sort of hidden fastener that clips or screws into the edge of the boards.
Tropical hardwoods are relatively expensive, especially when compared with PT lumber, but in most parts of the country they’re comparable in cost to redwood and cedar. The most common of all tropicals is ipe (EE-pay), which is also known as Ironwood or Pau Lope. It’s a beautiful hardwood that’s similar in appearance to mahogany, but with a darker, richer crimson color. A 1x6 of ipe costs about $4.50 per lin. ft.
Most tropical hardwoods are so dense they don’t accept stains very well. However, if you’re determined to apply a stain, be sure it’s an oil-based penetrating stain specifically formulated for hardwood decking. If you choose not to stain the deck, you should at least apply a UV-blocking clear wood preservative every three to four years.
Note that some builders suggest allowing the tropical hardwoods to weather one to three months before finishing, so that excess oils can leach out and the decking can then better accept the finish. And be sure to apply finish to both ends of each board and to every fresh end cut as extra protection against checking.
And like cedar and redwood, most tropical hardwoods will eventually weather to a soft silvery color, if they’re not stained. However, the amount and speed of any fading depends greatly upon the deck’s exposure to sun, rain and snow.
Lastly, when buying tropical wood, or any wood for that matter, check with your lumber dealer to ensure that the wood was certified by the Forest Stewardship Council, which is a nonprofit organization that identifies lumber that has been harvested in a legal, sustainable manner.
4 Composite decking—Composite decking and its cousin, “plastic lumber,” represent the fastest-growing decking materials sold today. In fact, while researching this piece, I visited a few online sources and found more than two-dozen companies that make plastic or composite decking. Most products are made from polyethylene, polypropylene or polyvinyl chloride, and come in a wide range of colors.
Composites, like MoistureShield, Trex, TimberTech, and Veranda, to name a few, are composed primarily of wood fibers and recycled plastic. The result is an extremely weather- and stain-resistant board won’t splinter, warp, rot or split.
Plastic lumber, like Azek Deck and Fiberon Paramount, is made from 100% plastic (recycled and/or virgin); it contains no wood fibers. It, too, is highly resistant to staining and decay, and free of knots, cracks and splinters.
Both composites and plastic lumber come in sizes similar to wood decking, including 2x4, 2x6 and 5/4 x 6 in. Prices vary widely because there are so many different companies, but composites are typically less expensive than plastic lumber. For example, for 5/4 x 6-in. decking, expect to about $3.50 per lin. ft. for composites, and $4 per lin. ft. for plastic lumber.
Most composite decking and plastic lumber manufacturers also offer a line of handrails, balusters, fascias and other decorative trim.
Now, not everyone likes the idea of installing manmade decking, but composite decking and plastic lumber do have certain advantages over wood: They’re extremely low maintenance, and never need to be sanded, refinished or stained. However, they’re not 100% maintenance free. Mold and mildew can grow in shady, damp areas of the deck, and some composites can eventually show signs of decay, which makes sense since they are part wood.
5 Aluminum decking—Ok, I admit it. I’ve never actually seen an aluminum deck—and perhaps you haven’t either—but that doesn’t mean aluminum isn’t worth considering for your deck. In fact, in some ways, it’s an ideal decking material: Aluminum decking, such as LockDry, Versadeck, and AridDeck, won’t rot, rust, warp, splinter, crack or check, and it’s extremely weather- mold- and slip-resistant. Its powder-coated finish lasts virtually forever and it’ll never peel or blister.
Aluminum can’t catch fire, wood-boring bugs hate it, and it’s cryogenically strong, meaning it doesn’t get brittle in extremely cold weather. And, it’s totally recyclable.
When compared with wood, composite and plastic lumber, aluminum decking is three to four times lighter, yet two to three times stronger. It can be cut with the same saws and carbide-tipped blades used to cut wood.
Most aluminum planks have interlocking edges, which create gap-free, watertight decks. Built-in, self-draining channels collect and divert rainwater, making aluminum decking ideal for second-story decks since the space below stays dry. And you might be surprised to learn—as I certainly was—that aluminum decking actually stays cooler in the sun than most other types of decking because of the metal’s superior heat-dissipation properties. Unfortunately, aluminum is the most expensive of these five decking options, costing about $10 per lin. ft.