Weight of Hardwood Lumber

Heaviest Lumber

• Lyptus, the heaviest hardwood lumber, weighs 4.40 pounds per board foot. Hickory and pecan both have board foot weights of 4.25 pounds. White oak weighs in at 4.10 pounds; red oak, 4 pounds; beech and sapele, 3.85 pounds; hard maple, 3.80 pounds; and yellow or white birch, 3.70 pounds.

Medium-Weight Lumber

• At 3.50 pounds per board foot, walnut is next heaviest, followed by mahogany at 3.45 pounds and cherry and soft maple at 3.30 pounds. Southern yellow pine weighs 3.27 pounds per board foot; ash is 3.10 and Pacific maple and Douglas fir are both 3.0.

Lightest Lumber

• The lightest eight types of hardwood lumber include poplar at 2.90 pounds per board foot, aromatic cedar and cypress at 2.80, Spanish cedar at 2.75 and Eastern white pine at 2.70 per board foot. The hardwood lumbers that weigh the least include Ponderosa pine, 2.67; basswood, 2.20; and alder, 2.15.

Lumber Drying Techniques

• The most cost-effective methods to dry hardwood lumber are outside air and solar kiln drying, both of which affect its weight. Outside air removes between 14 and 19 percent of moisture from green wood and makes it sturdy enough for framing and exterior applications. Lumber dried in a solar kiln reduces the moisture content between 7 and 8 percent, an appropriate moisture level for lumber used to make furniture and interior applications not exposed to extreme cold. Lumber requiring additional drying is placed in a dry kiln with precisely controlled circulation, temperature and humidity.

Effects of Hardwood Drying

• Before hardwood lumber is cut and sold, it is either air or kiln dried. The drying processes shrink the wood horizontally, across the grain, which makes it stronger. Drying also reduces the chances of decay or sap staining and if the moisture in the wood is dried below 20 percent moisture, it is nearly impervious to these types of deterioration. Hardwood drying also reduces its weight by at least 35 percent and increases the overall strength of most woods a minimum of 50 percent.