Creaking or buckling floors
moderate 1–3 h
Tools: drill, stud finder, hammer, pry bar, moisture meter (optional), flashlight · Materials: squeak-repair screws (breakaway type) or 60 mm (2½-inch) deck screws, construction adhesive, shims
Steps
- Walk the floor and mark every creak with tape; a creak is a board moving against a nail or a joist, and the fix is to stop the movement.
- Find the joists with a stud finder — they usually run 40 cm (16 inches) apart — and drive a screw through the flooring into the joist at each mark; a breakaway squeak screw snaps off below a finished surface.
- From a basement or crawl space, tap a shim coated in adhesive into the gap between the joist and the subfloor where it creaks; do not hammer it in so far that it lifts the floor.
- For a buckled or tented area, find the moisture: check the dishwasher, fridge line and any bathroom nearby, and measure the boards with a moisture meter if you have one.
- Once the source is fixed and the wood has dried for a few weeks, many mild buckles relax; cut a 10 mm (⅜-inch) expansion gap at the walls if the boards are jammed against them.
- Replace boards that stay cupped or split, working from a hidden spot like a closet for matching boards.
Stop and call a pro if
- the floor is spongy, sags, or the joists are wet or cracked when you look from below
- buckling covers more than a few boards or is spreading — a leak is still active
- the flooring is glued down over concrete and lifting in a wide area
What a pro does that you can't
A flooring contractor replaces a tented section with matched boards, re-secures a subfloor from above without a trace, and a plumber finds the slow leak that is usually behind buckling.
DIY cost: $15–40 in screws and shims