Q. I am building a new home. Even before installing the finished flooring, I noticed a couple of places on the subfloor where there is creaking and squeaking. How can I stop it? Gordon M. Kull Palo Alto, Calif.
A. Ideally the subfloor should be concurrently nailed and glued to all floor joists and blocking. Was it? If so, spot, glue, and renail at the offending squeaky places.
If not, discuss the problem with architect and builder. There may yet be a way to correct the problem, short of total subfloor removal and reapplication, of glueing and renailing the subflooring after the fact.
Was blocking installed between floor joists where the plywood subfloor joints occur? If not, I'd install blocking there. Otherwise, squeaking can occur from unblocked plywood sheets rubbing against each other under impact. Caution: If not originally glued and nailed, retrofitting of an in-place, squeaky subfloor may not be entirely successful without removal and reinstallation.
Squeaks in unglued floors usually occur when the subfloor moves up and down on nail shanks under foot traffic.