Lumber

Many different lumber sizes are used in the construction of wooden load bearing walls. The most common dimensions of lumber used in residential bearing wall construction are 2" x 4" and 2" x 6" (actual size 1 1/2" x 3 1/2" and 1 1/2" x 5 1/2"). Other typical sizes used for more critical members include 2" x 8", 2" x 10", 2" x 12", and 2" x 14" as well as 4" x 4", 6" x 6", and 8" x 8" posts.

The most common type of wood used in construction is pine (softwood) although, other types of wood are used for different applications. Most older homes tend to use large hardwood posts and beams to support their loads because they are very strong and will last a long time. More recently though, it is common to hide the load bearing members such as large posts and columns inside walls. This also helps to distribute the dead and live loads of a building to an entire length of a wall instead of one point through a beam.