Besides major problems, you may also experience scratching or loose planks with your hardwood flooring. Scratches can be repaired with touch up kits, or something as simple as a like colored crayon. If you’ve got serious scratching, however, you may need to hire a contractor to refinish the flooring altogether. And if you’ve got loose planks, your only solution is to tie them down. Ideally they should be nailed to the subfloor to prevent any more movement, though excessively loose boards can be a sign of improper installation in the first place. Bringing in a professional hardwood installer to re-install your flooring properly is probably the only sure way to permanently solve the problem. Denver Hardwood Floor Install

Eliminate any problem spots to make the subfloor level. Sand minor humps down with a hand-held or orbital sander to make the subfloor level. To fill any dips or low spots, use a leveling compound (also known as floor patch). Mix up the compound according to package directions, fill in the dips, then pull your straight piece of lumber back and forth over the spot to flatten and level it with the rest of the subfloor.[7] Hardwood Floor