A squeak is friction. Something in the floor assembly is moving against something else when you step on it, and the fix is always the same in principle: stop the movement. Everything below is a different way of doing that, depending on what is moving and whether you can get underneath.
Most squeaks are a fastening problem rather than a structural one, and most of those are fixable in an afternoon.
What Is Actually Making the Noise
Four possibilities, and identifying which one you have determines the fix.
- The subfloor moving against a joist is the most common cause by a wide margin. Nails have worked loose over time, so the subfloor lifts a fraction when you step and drops back, and the nail shank rubbing in its hole is the squeak.
- The flooring moving against the subfloor comes from loose or missed fasteners in the hardwood itself, or a gap between the flooring and the subfloor that lets the boards flex.
- Boards rubbing against each other happens at the tongue and groove edges, usually because the wood has shrunk and the fit has loosened. This gives a lighter, drier sound than the deeper thump of subfloor movement.
- A structural issue, such as a joist that has twisted, cracked, or pulled away from its support, or bridging that has come loose, is less common but the one you want to rule out.
Find the Exact Spot First
Do not skip this. Fixes applied near a squeak instead of at it are the main reason people try three things and nothing works.
- Walk it slowly in socks and shift your weight in small steps until you can make the squeak happen on demand.
- Have someone else walk while you listen from below, if you have a basement or crawl space. This is by far the fastest method, and you will often see the subfloor lift off the joist as they step.
- Mark the spot with painter's tape. Squeaks are surprisingly hard to relocate once you have moved furniture.
- Find the joists with a stud finder, which works through most flooring. Joists usually run 16 inches apart, and knowing whether your squeak is over a joist or between two of them tells you which fix applies.
Fixing It From Below
If you have access to the underside, this is the better approach in every case. Nothing shows on the finished floor and you can see what you are doing.
Shims into a gap
If there is a visible gap between the top of a joist and the subfloor, a wood shim coated with carpenter's glue, tapped gently into the gap, closes it. Tap it, do not drive it. Forcing a shim in lifts the floor and creates a hump upstairs and often a new squeak nearby.
Construction adhesive along the joint
For a long gap rather than a single spot, run a bead of construction adhesive into the seam between the joist and the subfloor on both sides. It cures into a gap filler and eliminates movement along the whole run.
A block glued and screwed to the joist
Where the subfloor has separated over a wider area, a length of two by four glued and screwed to the side of the joist, pressed up tight against the underside of the subfloor, supports it properly. Screws go into the joist, not up through the subfloor, so nothing reaches the finished floor.
Screws up through the subfloor
Short screws driven up through the subfloor into the underside of the hardwood pull the two together. The critical part is length: the screw must be shorter than the combined subfloor and flooring thickness, or it comes through the finished floor. Measure, then subtract a quarter inch, then check the screw against a scrap.
Bridging between joists
If the joists themselves flex or twist, solid blocking cut to fit between them and nailed in place stiffens the whole assembly. This is the fix when the squeak is broad rather than located at one point.
Fixing It From Above
Necessary on a slab, a second storey, or anywhere a finished ceiling blocks access. All of these leave some mark on the floor, so work in an inconspicuous spot first if you can.
Screws into a joist, set and filled
Locate the joist, drill a pilot hole, drive a trim screw at a slight angle through the flooring and subfloor into the joist, then set the head below the surface and fill it with matching wood filler. Angling the screw resists pull-out better than driving it straight down.
Done carefully and filled with the right color, these are close to invisible on a floor with visible grain. On a very uniform floor they show.
Snap-off screw kits
Sold specifically for this, these use a deep-thread screw with a scored head. You drive it through the flooring into the joist using a depth-control jig, then snap the head off below the surface. The remaining hole gets filled. They are the most reliable above-floor fix and the kit costs less than a service call.
Lubricating the seam
For board-against-board squeaks only, meaning the light dry sound rather than a deep movement. Work powdered graphite, talc, or dry lubricant into the seam between the boards with a stiff brush, then walk the area to distribute it. This is a temporary fix. It reduces friction without stopping movement, so the squeak usually returns in a few months.
Do not use liquid lubricants or oils on a hardwood floor. They soak into the seam, leave a residue that has to be stripped before the floor can ever be recoated, and can stain.
Refastening the flooring
Where the hardwood itself is loose from the subfloor rather than the subfloor being loose from the joist, the fix is face-nailing through the board near the seam, then setting and filling. Best done by someone who has done it before, because the nail has to miss the tongue and hit solid subfloor.
When a Squeak Is Worth Worrying About
Most squeaks are a nuisance, not a warning. These are the ones that are not:
- A squeak that appeared suddenly in a floor that was quiet for years, particularly with no change in season.
- A soft or spongy feel along with the noise, which suggests the subfloor has lost strength rather than just fasteners.
- Noticeable deflection, meaning the floor visibly drops when you step on it.
- A squeak that comes with cupping, staining, or a musty smell, which points at moisture rather than ordinary wear.
- Cracking rather than squeaking, a sharper sound that can indicate a fastener or a joist failing.
- Doors and trim in the same area going out of square, which suggests movement in the structure rather than the floor.
Any of those is worth a look from someone before you start driving screws into it.
Why Squeaks Come Back Seasonally
Wood shrinks in dry winter air and swells in humid summer air. A floor that squeaks every January and goes quiet in June is responding to that cycle, and the fasteners are loosening slightly as the wood contracts.
Keeping indoor humidity between roughly 35 and 55 percent year round reduces the swing and often reduces the squeaking with it. A whole-house humidifier on the furnace does more for a seasonal squeak than any amount of screwing.
Squeaks Under Carpet
Same causes, and a slightly easier fix, because you do not have to worry about the finished surface. Snap-off screw kits are designed to work through carpet: the jig compresses the pile, the screw goes through carpet and pad into the joist, and the head snaps off below the pile line. Work the fibers back over the spot afterward and it disappears.
If you are planning to replace the carpet with hardwood anyway, fix every squeak while the subfloor is exposed. It is the single easiest time to do it, and it is far cheaper than doing it later through a new floor.
When to Call a Professional Instead
Most of what is on this page is a reasonable DIY project for anyone comfortable with a drill and a bit of patience. Call someone instead when you cannot get access from below and the squeak is spread across a large area, since that usually means more holes and more filling than is worth doing yourself. Call someone when the squeak is one of the warning signs above, since that is a diagnosis question before it is a repair question, and a flooring contractor or a structural professional needs to see it rather than hear a description of it. And call someone when a snap-off kit or trim screws have not worked after a real attempt, since a squeak that resists the standard fixes is usually telling you the cause is not what you assumed.
Squeak You Cannot Track Down
Some squeaks are stubborn, and a few turn out to be something other than fasteners. TriArt Hardwoods repairs hardwood across Atlanta, Johns Creek, and Sandy Springs. See our hardwood floor repair service or get in touch.
