Deck Building: Materials and Construction Basics
Photo By: Trex
Photo By: Lydia Dotto, ImageInnovation Photography
Photo By: Photographer: Matthew Borkoski
Photo By: Chuck Collier Schmidt
What to Know Before Building a Deck
If you're going to install a deck, even if you're hiring a professional to build it, it's always a good idea to arm yourself with information. That way, you won't wind up with a deck that doesn't fit your needs or, worse, is dangerous. After all, your friends, family and visitors will likely spend time on your deck; choosing the best materials and construction methods is crucial. Photo courtesy of Trex
Piers are the unsung heroes of any deck. A pier, dug into the ground and attached to a footing pad on the deck, is a heavy piece of material sometimes wood but often made of concrete that stabilizes your deck. Think of how much weight a deck needs to support: you, your family, your furniture and additional guests, if you throw a party. If a deck is built without piers, the structure will likely sink into the ground.
A ledger, in deck-speak, is a board that attaches the deck to the house. Not all decks are attached to houses, but if yours is, the ledger is a crucial component. If the ledger is not properly installed and pulls loose from the wall, the entire deck could collapse and gash your home’s exterior.
A good builder will add what's called flashing to the ledger. "Flashing is something that goes up against the ledger and stops water from going into the home or seeping into the brick and then into the house. A lot of times, when that step is missed, depending how the rain water falls on the patio, you can have rotting problems," says landscape designer Darin Brockelbank, founder of Metro GreenScape, a company in Charlotte, N.C., that specializes in designing and building environmentally friendly outdoor living spaces.
Of course, you can forget the ledger and go with a freestanding deck. Although about "80 percent of homes have ledgers," says Mel Karlson, senior marketing manager and head of contractor development at Trex.com, the nation's largest manufacturer of wood-alternative decking, railing and fencing products, there are some good reasons to build a freestanding deck.
Brick homes, for instance, can have attached decks, but freestanding decks are often a better choice. "If the footing of the brick wall is strong, and the wall itself is a solid width of at least 12 inches, reinforced with rebar, then you can connect a header attached directly to the brick with lag bolts to adhere the deck to the brick with no problem," says Darin. "This will effectively support the structure." Metro GreenScapes has done numerous decks with brick homes or walls in this manner. However," he cautions, "if home design allows additional posts, that is the preferred method of construction against the brick."
Some engineers and builders prefer freestanding decks, built just one inch away from the house, to prevent harm to the exterior. In this case, your deck parts, such as the piers, become even more important as they prevent the deck from wobbling.
Deck Beams and Posts
Beams and posts work together to support the weight of the deck. Beams (horizontal) rest on the footings, carry the joists and offer support to the surface decking. Posts (vertical) determine the height of the deck and provided they're installed properly – support the beams and offer the deck stability. A couple of loose posts will leave you with a very unsteady deck. The higher a deck is, the more important the beams and posts become. But no matter how high or low to the ground your deck is, you want to be careful, thoughtful and methodical during every step of the deck-building process.
On that note, your deck should primarily be assembled with screws rather than nails. "You have a rust element, and they aren't as strong," Darin says. "A lot of times you'll see bubbling in the wood, and that nail will start coming out, where a screw has a wider head, and it holds everything in place and minimizes that risk."
Joists are wooden planks that maintain the deck's structure and serve as a foundation for floorboards. They usually run perpendicular to the house and hang between the ledger board attached to the house and a beam. You'll also find them between two self-supporting beams.
When selecting joists, check the board for defects: A knot on the underside of a joist won't support weight indefinitely.
Material Options: Wood
Pressure-treated wood is generally the least expensive material, Darin says. "Typically, a wood deck will cost around $15 a square foot, though prices always vary depending on where you live. Some cedar will cost around $20 a square foot."
Cedar, the most popular wood species, is beautiful (red cedar, for instance, ages to a silver color), fragrant and extremely resilient. Cedar does splinter easily but is weather resistant, if stained annually.
Redwood and pressure-treated pine are also favorites for their durability and appearance.
Material Options: Composite and Stone
Composite material, whether recycled plastic, resin, polyester or glass fiber, is generally going to be one and a half to three times more costly than lumber. Trex is a popular composite made from reclaimed and recycled materials, such as waste wood fiber and reclaimed plastics. While it's more expensive than treated lumber ($25 a square foot, says Darin), it does not shrink, splinter or fade.
Travertine, a limestone mined for various building purposes, is gaining in popularity as a patio and deck material. It costs $50 to $60 a square foot, according to Darin. Photo courtesy of Trex
Adding steps to the deck staircase will bump up construction costs. "The average staircase can cost $5,000," says Darin. It's not the stairs themselves that add extra digits, he says. It's the fact that an additional level requires more joists, beams and posts – more of just about everything. And along with additional levels come railings, which can add about $2,500 to a deck.
Cost should be taken into consideration throughout the deck-building process. A curved deck can be 50 percent more expensive than a square, boxy-shaped deck, simply because more cutting is required, Darin says. Photo courtesy of Paver Pro
When it comes to railings, prices run the full spectrum. Pressure-treated wood costs $15 per linear foot, while manufactured glass can cost $125 per linear foot. In between, options include composite wood, exotic wood, stainless steel cables and aluminum.
Balusters, or posts that are attached from the top of the railing to the bottom, are another component to consider. Wood posts are a traditional choice, but cable and glass balusters are growing in popularity because they provide unobstructed views.
Extras to consider include trim, which can camouflage joists, screws and other unsightly hardware. Photo courtesy of Paver Pro
Complicating matters is geography, which can be your deck's best friend or most bitter enemy. What's solid, weather-resistant material in Alaska may not be weather-friendly under the baking sun in Arizona. Do your homework when you buy your lumber or material. Your contractor can also make recommendations.
And it's just as important to make sure you're up on building codes, says Mel, adding that code information is often posted on state, city and county government websites. "Some counties require half-inch leg bolts into the ledger, so if you or your contractor uses 16-inch penny nails instead, then there's a problem with not understanding the code."