Oak is the most popular wood for flooring, and the most harvested hardwood in North America. This flooring has a smooth surface with a 3mm wear layer. The red oak has been heat-treated which changes the color of the wood. It’s suitable for above and below grade installations and additionally over water-based radiant heat systems. It can be nailed, glued or floated. Natural variations and occasional knots are allowed in this grade. The finish wear-through warranty is 25 years for residential applications. The structural warranty is lifetime.