Building decks provides outdoor living spaces. Problem is, you don’t know where to begin, you say? Your do-it-yourself carpentry skills are basic at best, and the prospect of deck design and construction from scratch is rather daunting? Thats were we can help. To further enhance your outdoor living spaces, find out how we can build wooden garden arbors — pehaps right over your decks!
Introduction to Pressure Treated Decking
Wood can be impregnated with a variety of preservative chemicals to prevent rot and insect infestation in exterior applications like decks. Several species of wood can be treated, but a regionally available species usually predominates in any particular locale. Pressure treated lumber is ideal for outdoor construction as it has a long, useful life span and is much less expensive than alternatives. Treated wood can last more than 40 years. The treatment process involves placing a load of lumber in a huge cylindrical chamber called a retort with a door on one end that can be sealed airtight and then forcing waterborne chemicals into the wood under pressure.
Lumber Grading Standards
Many lumberyards stock treated wood in the broad category of #2 or better. If this is the case you may want to sort through the lumber piece by piece to find clear, straight boards. Because treated wood is often still wet when it is delivered to the site it will shrink slightly in width and thickness as it dries out. This can cause significant twisting, cupping, bowing, and warping especially in lower grade boards where knots and uneven grains are already present. It is possible that some boards will become so deformed that they will be unusable. You may want to store lumber by fastening boards together using a method called stickering to allow boards to dry evenly. You may also purchase kiln dried after treatment (KDAT) which is much more stable but also more expensive.
Premium – Highest grade for 5/4 radius edge decking.
Select – The highest grade available, contains very few detects. It must meet a minimum 1/12 grain slope and have all knots sound encased. It has a high consistency and the appearance is very good.
#1 – Will contain no splits larger than the width of the board. Knots may not be larger than 2 ¾”. Holes appear every 3 ft.
#Standard – Midrange greade for 5/4 decking.
#2 – Grain slope must meet minimum 1/8 grain slope. Boards will contain no splits larger than 1.5 times width of board. Knots may not be larger than 3 1/2:”. Holes appear every 2 ft. Wane corners.
#3 – The lowest quality grade. Not suitable for deck construction.