Silencing a squeaky floor

With the weight of us and our possessions on top of them, it's no wonder floors eventually begin squeak and flex over time. Fortunately, these are easy problems to fix before they drive you crazy. 

• Floors squeak when the floorboards rub together or against nails. If the squeak is minor, you can often fix it by simply putting talcum powder between the boards to act as a lubricant.
• Sprinkle the powder over the crack between the offending boards, cover with a towel, and rub in the powder with your foot.
• If the gap above a joist is particularly wide, try putting a shim into it to silent the squeak. You can get a package of ready-made shims at a home centre. Put construction adhesive on both sides of the shim. Then put a block of wood against the end of the shim, and hammer the wood block to drive in the shim. Clean up any stray adhesive with paint thinner.
• If the floor has a wax finish, try pouring liquid floor wax between the floorboards. Don't try this on a varnish finish.

• Sometimes a squeak or a bouncing floor results from a gap between the floorboards and subfloor. If you suspect this, drive screws from below through the subfloor and into the floor.
• Drill pilot holes and have someone stand on the floor above as you drive the screws in. Use screws no more than three centimetres (1 1/4 inches) long so that you don't poke through your finished floor.
• Slip a washer over the screws before you drive them to keep the screws from going in too far.
• If you can get underneath the floor — from the basement or a crawl space — try silencing a squeak with your hot glue gun. Have someone walk across the floor so you can pinpoint the squeaky spot. Look especially for gaps between the subfloor and the joists supporting it. Then apply hot glue along each side of the joists.
• Instead of hot glue, you can inject polyurethane caulk into the gaps between the joists and the subfloor. Push the caulk into the gaps with a plastic spoon.

• Another way to reinforce joists is by nailing strips of two centimetre (3/4-inch) plywood to them. Put the strips on one side of the joists or both, depending on how bouncy the floor is. Have your lumberyard cut strips of plywood to the same width as the joists.
• Apply construction adhesive to one side and the top edge of a strip, put it against a joist, and nail it in place with two rows of nails, staggering them so that no nail is directly above another.
• Floors flex because there isn't enough support beneath them. Add support by putting diagonal bridging between the joists. Metal bridging, sold at home centres, is easy to install under floors with accessible joists. Just drive a nail through each end of each crosspiece to attach the bridging to the joists.
• Leave a space between pieces of bridging so they don't rub together and make noise.