The subfloor is the foundation of your hardwood flooring, and any imperfections here will manifest in the finished product. To meet NWFA guidelines, the subfloor must be structurally sound and free of debris, which can cause squeaking or hollow spots. The most critical requirement is flatness. If the subfloor is not level, you risk having gapping, joint stress, or floor noise. We measure flatness using a straight edge, ensuring the variance does not exceed 3/16 inch over a 10-foot radius. Any high spots must be sanded down, and low spots should be filled with a professional-grade leveling compound. In addition to structural integrity, moisture management is paramount. We use pinless moisture meters or RH probes to verify the moisture content of wood subfloors and check concrete slabs for MVER compliance. If the subfloor is too damp, the hardwood will absorb that moisture, leading to cupping or buckling after the installation. Ensuring the subfloor meets these rigorous standards before laying a single board is the mark of a professional installation and is essential for maintaining your flooring warranty.
Key considerations
- subfloor requirements for hardwood
- how flat does subfloor need to be
- moisture check subfloor
- Subfloor
- Preparation
- Levelling