How to put an end to the stubborn creaks
The floors in our one-story house squeak. I've noticed when I'm in the basement that there's no cross bracing between the joists. Will the squeaks stop if I add cross bracing?
— Mike, Chesterfield, Missouri
Tom Silva replies: Probably not. Cross bracing — also called bridging — stiffens the
floor and helps prevent joists from twisting. The reason most floors
squeak is because either the finish floor or the subfloor is loose and
rubbing against a popped nail; no amount of cross bracing will fix these
problems. Instead, you have to tighten up what's loose by toe- nailing or screwing the floor back to the joists.
To pinpoint the source of the squeaking, have someone walk around upstairs while you're down below, watching and listening. Have with you a drill with a bit slightly bigger than the shank of a 2 1/2-inch screw. In every spot where you hear a squeak and see the subfloor move at the same time, drill a pilot hole at
a 45-degree angle into the side of the joist, 1 1/2 inches down from the
underside of the floor. Do not drill into the subfloor. Now have your
buddy stand in that place while you drive a 2 1/2-inch screw into the
pilot hole, through the subfloor, and partway into the finish floor. (Do
so with care; you don't want the screw to go through the finish floor,
or into your helper's foot.) Driving another screw at the same angle
through the other side of the joist should stop any further mouselike
By the way, it's not unusual for a house to not have cross
bracing. Some building codes don't require it unless the joists are
bigger than 2x12. On spans greater than 9 feet, I like to put solid
blocking the same depth as the joist down the center of the span.