Seasoning of wood is a crucial process aimed at reducing and stabilizing the moisture content within the wood to prevent future shrinkage, structural damage, or aesthetic issues once the wood is used in construction. Wood naturally swells when it absorbs moisture and contracts as it dries.
Achieving equilibrium moisture content is the goal of seasoning; this is the point where the wood's moisture content stabilizes to align with the moisture levels of the surrounding environment. Proper seasoning ensures that the wood does not shrink post-construction, maintaining structural integrity and appearance.
There are two primary methods of seasoning wood: air drying and kiln drying. Air drying involves stacking lumber loosely in layers, elevated from the ground spaced adequately to allow for good air circulation, and protected from moisture with a waterproof roof. This method aligns the wood to prevent warping as it dries.
Kiln drying, on the other hand, accelerates the drying process within a controlled environment, arranging the wood similar to air drying but within a kiln. Standard framing lumber is typically dried to a moisture content of 19 percent to ensure stability, while structural lumber may be dried to 15 percent moisture content to control shrinkage effectively.
Seasoned lumber might exhibit distortions, which vary depending on the wood's original position within the tree. These methods of seasoning are essential to prepare wood for its various uses in construction, ensuring durability and longevity.
