Have someone walk, not run, so don’t ask the kids to help,
around the offending floor. Listen and try to pinpoint the exact spot a squeak
is coming from. Mark out this section of the floor with some of that police
line tape. Ordinary masking tape, or even chalk, will do in a pinch.
Now, if you don’t want to get into doing a permanent repair
job right away, you can squirt some powdered lubricant into the cracks around
the bad boards. This is a temporary fix and won’t last, but it will give you
some peace for a while. Powdered graphite will work, as will any of the white
powdered lubricants you can find at a hardware store. Squirt the stuff into the
cracks and then step on the board a few times to work it in. It works, but the
squeak will be back like a bad rash.
If this doesn’t work, the squeak is likely coming from the
subfloor. In that case proceed to the basement, and take along a flashlight.
If there is an unfinished basement beneath the squeaky area,
you will be able to access the squeak. Have someone else walk around above.
Listen and watch to pinpoint the squeak. Then, watch while the person above
steps on and off the squeaky boards. If the subflooring moves up and down, it
is the culprit. If the subfloor doesn’t move, the problem is the finished
flooring.