Q: I have a plywood subfloor with a few high/low spots. I’ve read that laminate flooring can only be installed over flat subfloors. Is there any way I can flatten it?
A: High areas, such as peaked joints in the subfloor or other ridges in the wood subfloor can be power-sanded or planed. Low areas that are less than 1/4-inch deep can often be filled with building paper. Any area where the surface dips lower than that should be filled with a Portland cement and latex-based leveling compound, or covered with some sort of rigid underlayment. When using a leveling compound, be sure to follow the manufacturer’s recommendations, and allow the compound to dry completely before installing the laminate flooring.