Engineered wood flooring looks very similar to solid wood on the surface. However, the construction is different, the top layer is actual wood bonded over a substrate of high-quality plywood. The amount of sanding available will depend on the thickness of the top wood layer and floorboards tend to be wider with engineered hardwood flooring. Engineered hardwood has better performance in humid locations since its plywood construction makes it more stable and less susceptible to warping caused by moisture.
Solid wood flooring, as the name suggests, is made of solid wood throughout its thickness. It is usually made of a hardwood species, such as oak, maple, or walnut, and tropical woods. Its major advantage is that it can be sanded many times over the course of its lifespan. Solid hardwood flooring boards tend to be narrower than engineered hardwood flooring.