Question: what are the layers of flooring?
Answer: Joists. Joists are the first, lowest layer of flooring and support everything above. ...  Subfloor. The subfloor is the next layer above the joists and acts as a foundation for both the underlayment and surface levels of flooring. ...  Underlayment. ...  Surface. ...  Plywood. ...  Oriented Strand Board. ...  Particleboard. ...  Concrete.