Should You Build a Deck with Wet Wood?

Shrinkage

• Wood shrinks as it dries. When wet wood is cut to fit a deck size, the shrinkage can cause a variety of undesirable effects. Nail pops occur when a nail head is forced out of the wood as the surrounding wood strains from shrinkage; if the shrinkage is sufficient, it can even split the wood from the pressure of the nail holding it down. Cracks appear between boards as they draw away from one another, and boards can warp and become twisted.

Staining and Painting

• Traditionally, deck builders have been told to let a deck sit for several months to "let it dry out" before staining or painting. This is because stains and paints don't do well on wet wood, and the extra time is necessary to season the wood. However, the sun and weather during this period can adversely affect untreated wood and cause more work for the homeowner. Oxidation will have already set in on the wood, which must then be sanded off before any stain or paint is applied, and moisture will have seeped into the cut ends of the studs.

Under Cover

• The alternative to buying kiln dry wood or wet wood is to season the wood yourself after buying it but before building with it. Draping a tarp over the wood is not good because it traps the moisture underneath and becomes a good breeding ground for insects, mildew and mold. Storing it in a garage, a greenhouse or even a surplus Army tent provides the necessary shelter for drying.

Ready to Build

• Holding wet wood several months in a protected environment allows the bulk of moisture to evaporate out, and a few months of preparation saves trouble down the road. The wood should be stacked off from the floor and so that air circulates freely between all the pieces. A house fan blowing over the wood can dramatically increase the moisture loss and reduce the time for drying. When you're ready to build, take a stud back to the lumber yard and have its moisture content measured with a hydroscope.