Selecting the proper type of lumber for the specific project is important for two reasons. First, the strength and durability properties of various types of lumber vary significantly. Second, some types of lumber can cost four to five times more than others, so you want to select the least expensive type that satisfies the project requirements.

Lumber can be broken into two types: framing and finishing. In general, framing lumber is strong and durable, but not seen when the project is complete. Finishing lumber is exposed, so its appearance is often more important than its strength.

Another distinction for lumber is the type of tree it comes from, either softwood or hardwood. Softwoods usually refer to coniferous trees (needles) and hardwoods refer to broadleaf, deciduous trees. For framing, softwoods, such as pine and Douglas fir, are most often used.

This hardwood-softwood distinction does not necessarily relate to the actual hardness of the wood itself. Poplar, a hardwood, is softer than yellow pine, a softwood. Softwoods, such as cedar and redwood, have natural resins that resist rot and insect damage. Yellow pine is very strong and stable for framing, and it also can be easily painted with good results.

The surfaces of hardwoods can be finished more cleanly than softwoods, so they are more often used for finishing lumber. Typical finishing hardwoods are maple, walnut, cherry, oak and ash. They are considered to be higher quality lumber, and more work is done to create a smooth surface, so their costs are higher than yellow pine lumber.Particularly among softwoods, there are many grades from which to select. The three characteristics that determine the lumber grade are surface appearance, surface quality and strength. The grade of lumber that is 1-inch thick or less is based upon its best side, since only one side is usually visible. Check the backside to make sure there are no significant imperfections that might affect strength.

Unless you are a cabinetmaker, most of the lumber you use for remodeling projects is called common lumber. The grading system for common lumber ranges from 1 (best) to 5 (worst). For most home projects, grades 1 through 3 are of adequate quality.