Unfinished solid or engineered hardwood is sold in the form of non-varnished rough boards. Solid hardwood have to be nailed to a wood sub-floor. An engineered floor can be glued directly to concrete. A wide variety of species, grades and widths are available.
This flooring is installed, but finishing the surface is more complicated and has to be done on-site. You have to pay for finishing, as well as the cost of the wood. We sand and stain the floors, then apply 3-4 coats of polyurethane for the desired finish.
A pre-finished engineered hardwood flooring is sold as boards made up of a hardwood surface ( called the wear layer) glued on a plywood base. Developed for installation in areas with variable humidity levels, engineered flooring is more stable than solid wood. The boards can be glued directly onto concrete. They can also be stapled to a plywood sub-floor. This is the perfect floor for any area.
Pre-finished solid hardwood is sold as ready-to-install wood boards that are already sanded, stained and finished with multiple coats of polyurethane with an aluminum oxide protective finish. The finish is factory applied in an ideal, controlled environment.