Solid wood floors are made from a single piece of wood that has been cut in one piece directly from a tree and then constructed into planks with tongue and groove edges. You can purchase the flooring materials as either pre-finished or unfinished in many American wood species as well as exotic imports. The investment for hardwood flooring is a little higher due to the cost of installation and the cost of wood. But when you consider its longevity the investment is well worth it and will bring a return on investment.The finished floor typically consists of long thin strips of wood that have been nailed into a wood subfloor. Since you are dealing with natural wood it can react to fluctuations in humidity, and you may notice expanding and contracting as moisture levels change. Proper installation is crucial to prevent buckling or gapping. Solid wood flooring is ideal for rooms with heavy foot traffic but not recommended in bathrooms or other rooms with high humidity and moisture. Solid wood planks can range in thicknesses from 5/16 to ¾ in and a typical width of 2 ¼ to 5 in. This type of flooring is installed over a wood subfloor and best suited best for installations at or above ground level. Hardwood floors can be sanded bare and refinished several times to renew their beauty and give it new life.