A backyard deck is the perfect gathering place for family and friends during nice weather, and it can be a valuable addition to just about any home. It’s a great place to socialize, relax after a long day at work, cook a meal on the grill, or stargaze after the sun goes down.
Building a deck is a relatively easy and straightforward process, as long as the deck lumber you are using is the right type for the job and of decent quality. Here are a few tips to help you find the right deck lumber for your project:
Select the Right Type of Lumber
The most common material used for decks is pressure-treated yellow pine, which is both inexpensive and readily available. It is treated with chemicals to make it resistant to moisture damage, fungal decay, and insect infestation. When compared to other materials, it is easier to work with and can be cut, drilled, sanded, and fastened together using simple hand or power tools. On the other hand, it has a relatively short lifespan of about 15 years, and it must be constantly resealed to keep it protected from the elements. It also requires special handling during cutting, drilling, and installation due to the harsh chemicals used to give it moisture resistance, and it has a tendency to shrink, warp, and twist, like any natural wood product.
Two common alternatives to pressure-treated deck lumber are cedar and redwood, both of which are naturally resistant to moisture, fungal decay, and insects. Both can last up to 20 years when exposed to the elements with regular resealing, and they are easy to work with. Unfortunately, both cedar and redwood cost significantly more than pressure-treated lumber and are softer woods, leading to greater damage from impacts and foot traffic. They are also susceptible to twisting and warping, as well as sun damage.
Hardwood decking is another natural alternative to pressure-treated deck lumber and it offers a variety of great looking species, such as Brazilian hardwoods. Like cedar or redwood, hardwoods are naturally resistant to moisture, fungal growth, and pests, and with proper maintenance they can last 25 years or more when exposed to the elements. They have interesting grain patterns and exotic looks that cannot be matched by pine, cedar, or redwood, but they are also much heavier and harder to work with, requiring pre-drilling for all holes and high-quality saw blades to cut the material efficiently. Hardwoods are also much more expensive than other natural wood products, and they still require periodic resealing.
As an alternative to natural wood products, composite deck lumber is becoming more popular due to its significantly reduced maintenance requirements, better resistance to the elements, greater uniformity, and wider selection of patterns, colors, and textures. Composite products, such as Fiberon decking, use a unique combination of wood particles and plastics to create a long-lasting material that can endure the elements for well over 25 years, with some products featuring a lifetime limited warranty. Compared to natural wood products, composites are environmentally-friendly, sustainable, durable, lightweight, and easy to work with, but because they last significantly longer than natural wood and are more expensive to manufacture, they tend to cost more.
Choose Quality Lumber
When using natural wood decking products, you must carefully choose the lumber for your deck to avoid problems with decay, twisting, warping, cupping, or splitting. For decks made with pressure-treated lumber, it’s important to first choose the appropriate chemical concentration for the application. Boards used for the deck or floor can have lower chemical concentrations because they will only be exposed to intermittent moisture. For posts or other lumber in constant contact with the ground, a medium concentration will be necessary. For wood that is submerged in water, high concentrations are needed. The exact concentrations will depend on the type of wood used and the specific chemical treatment.
Second, you must check each board or post for defects, such as crowning, warping, splitting, scalping, or twisting. As a natural product, each piece of lumber will have some defects, but by inspecting each piece you can obtain the best quality lumber. Lesser-quality lumber can be used in places where it is hidden, such as joists in the center of the deck or where short lumber is used and bad sections can be cut off.
When selecting pressure-treated posts, avoid those with large areas of heartwood from the center of the tree, as it is denser and cannot absorb the chemical treatment as easily. For cedar or redwood boards, choose ones with a greater amount of heartwood because it has better resistance to decay and moisture. Avoid using boards for the deck floor that are extremely wide, such as eight inches or larger, because they will be more prone to cupping or pulling away from the joists.
Finally, choose deck lumber that is as dry as possible to avoid twisting, cracking, and warping. Wet wood will shrink as it dries and it often dries unevenly, leading to damaged boards or gaps between adjacent boards. Due to the treatment process, pressure-treated lumber will naturally have more moisture than kiln-dried lumber, so plan accordingly for shrinkage.
Properly Size the Lumber
The overall design of the deck will have a large influence on the type of deck lumber you use. Small decks can be assembled using 4-inch square posts, while larger decks or decks that are higher off the ground may require 6-inch or 8-inch posts. Floor joists will have to be sized according to the length that they will span. For example, on 16-inch centers, 2×6 boards can cover a 9-foot span, while 2×8 boards can handle 12-foot spans, 2×10 boards can be used for 14-foot spans, and 2×12 boards are required for 16-foot spans. For deck boards, 4-inch widths will require longer installation times, while larger widths will be more prone to damage. Six-inch wide boards tend to be the best for most circumstances.
With careful planning and design, as well as the right type of deck lumber, it will be easy to build the deck you have always dreamed about. There are many free tools available online to help you through the planning process, such as the design tools from Fiberon, and with the right supplier you can get all the products you need in one place.