Solid and Engineered Wood Flooring Solid wood flooring is a solid piece of wood from the top to the bottom. The thickness varies from ¾” to 5/16”. Those wood floors can be installed both above and on grade, and they can be sanded and refinished during its service life. Engineered wood floors from other side are also real wood floors made by using multiple wood or wood composite veneers. The veneers can be from the same or from different wood species. It have a great stability because the grain of each veneer runs in different direction. This mean that the wood will resist expanding and contracting during fluctuations in humidity and temperature which is really making it wide usable. This type of flooring can also be sanded and refinished and it can be installed above, on or below grade.