Building a new deck can be a great way to expand your living area into the outdoors. If you want your deck to look fantastic, stay strong, and be durable enough to withstand exposure to the elements, then learning to choose the correct lumber building materials is essential.

Here are three tips you can use to ensure you get the right kind of lumber for your next deck project.

1. Buy pressure-treated lumber with the right amount of pressure to get the job done right.

Most homeowners know that pressure treated lumber is the best for outdoor building projects, but few take the time to realize there are different types of pressure-treated lumber available on the market. Varying amounts of pressure are used when treating lumber to achieve specific outcomes.

For your decking, railing, and fencing material, you will want to find a pressure-treated wood that is rated for above-ground use (treated with 0.25 pounds of preservative per cubic foot). Posts and beams should be constructed from lumber rated for ground-contact use (treated with 0.40 pounds of preservative per cubic foot). Using the right type of pressure treated lumber will help your deck last.

2. Avoid pressure-treated lumber made from heartwood.

Heartwood, which is the innermost part of a tree, is not well suited for pressure treatment. When water and nutrients can no longer reach the innermost part of the tree, it begins to die.

Compounds like resins, phenols, and extractives begin to collect within the heartwood, because no water is available to flush them out. These compounds make it difficult for the preservatives used to pressure treat the lumber to fully penetrate the wood. As you search for lumber for your deck, be sure that you are avoiding heartwood pieces, since these may not be fully pressure treated.

3. Look for pressure treated lumber that is fully dry at the time of purchase.

The preservatives used to pressure treat lumber are delivered via water. As the wood cells open up to take in the water, it can take some time for them to dry out and close back down again. Using lumber that is still wet from pressure treatment could result in gaps or buckling in your deck when the wood shrinks down as it dries.

To avoid the problems associated with wood shrinkage, look for pressure treated lumber that is marked as KDAT. This stands for kiln dried after treatment, and ensures that you will receive evenly dried lumber for your new deck.

Starting out with the right materials is essential when it comes to building a quality deck. Look for pressure-treated lumber that isn't cut from heartwood and has been kiln dried, and you will be on your way to building a deck your family can enjoy for years to come.