Solid hardwood, whether preﬁnished or ﬁnished on site, can be sanded and reﬁnished many times. It’s also susceptible to changes in humidity, and will expand and contract with the changes of seasons. Engineered hardwood is less susceptible to changes in humidity, and won’t expand and contract the same way solid wood can. Engineered wood is made of real wood glued to several layers of wood underneath, like plywood, or other types of materials such as corn. Depending on the thickness of the solid wood top layer, it can only be sanded and reﬁnished once or twice, but it has excellent stability over time. It is recommended to use a material such as engineered, laminate, or luxury vinyl tile in places such as basements.