Wood Decks

With the introduction and availability of pressure-treated lumber, wood decks have become more popular than ever. Pressure-treated lumber is impregnated with various types of salts which prevent wood decay. This type of lumber is available in various grades; from lumber that can be in contact with the ground, to appearance-trade lumber which can be used for the portion of the structure most visible.

The use of pressure-treated lumber by itself is not enough to guarantee the quality of the deck. Well-built decks are characterized by the following:

  • A deck may not need a foundation as hefty as that of a house, but it does need a good foundation. The best foundations for decks tend to be poured concrete footings with metal post saddles. Small decks or those low to the ground can be built on concrete pier blocks.

  • If the deck is fastened to the house, it must be flashed in a way that will prevent water entry to the house.
  • Nails and other fasteners, as well as flashing, joist hangers and hardware must be resistant to water and weather. Under normal conditions, hot-dipped galvanized material is a good choice. If your deck is near salt water, you may want to use stainless steel.
  • Some pressure-treated lumber has the capacity of withstanding soil contact for 40 years and more, but it will most likely last longer if it is kept out of the soil.
  • Pressure-treated lumber will tend to crack if not coated with a water sealer. The water sealer should be applied at the time of construction, and subsequently every 3 years.
  • Decks built with non pressure-treated lumber, including decks built with cedar, require periodic treatment with a wood preservative. Old growth cedar "heartwood" lumber has a relatively high resistance to rot. But most of the cedar we find in the lumber yard is relatively young "sapwood" and will start to rot in a few years unless it is treated at construction time and every 3-5 years hence. Even if you find and can afford top-quality cedar, the application of a wood preservative will help protect your investment, and a quickly disappearing wood product.

    Materials avaialble at Dunn Lumber.