Shaw Solid Hardwood is made from a single piece of real wood that has been milled into planks for flooring. Solid wood flooring expands and contracts with changes in your home’s relative humidity. Normally, installers compensate for this movement by leaving an expansion gap between the floor and the wall. Base molding or quarter round is traditionally used to hide the extra space. Hardwood Floors are more susceptible than an engineered floor to the natural expansion and contraction that occurs with wood. Therefore, Shaw Solid Hardwood should never be installed below ground level because of the excessive expansion and contraction. It should also never be installed over a concrete sub floor. These floors are easy to clean and care for. Solid Hardwood will cost more than an engineered floor.