Fix squeaky floors from underneath, by NickyDoes on YouTube. 3 min 54 s.
- Video length
- 3 min 54 s
- Time to do it
- 20 minutes
- Difficulty
- Easy
- Steps
- 7
What you need
Steps
Ask someone to walk slowly across the floor above while you listen from below. Mark the joist right under the loudest spot with chalk or tape.
Set up a work light or headlamp and put on safety glasses. Check the area for pipes, wires and ducts before you touch anything.
Look at the top of the joist where it meets the subfloor. A gap of about 1/8 inch or more lets the floor move and squeak.
Push a bead of construction adhesive into the gap with a putty knife. This alone can silence a small squeak once it sets.
Coat a wood shim with wood glue and tap it into the gap with a hammer until it feels snug. Do not force it. Snap the extra off flush.
For a wide gap, cut a 1x3 cleat and screw it to the side of the joist so it sits tight under the subfloor. Use 2 inch wood screws.
Have your helper walk the floor again. Mark any spot that still creaks and repeat with another shim or cleat.
Tips and common mistakes
Shims tapped too hard can lift the floor and crack the finish above, so stop as soon as the shim feels tight.
Never drive a screw upward until you know what is behind the subfloor. Pipes and wires often run through joist bays.
Glue and shims work best in dry weather. A squeak that returns in winter may need a screwed cleat as well.
Questions
Can I fix a squeaky floor from underneath if I have no basement?
No. Without access below, fix it from above by driving screws through the finished floor into the joists, then filling the holes.
What actually causes the squeak?
The subfloor rubs against a joist or a nail shank when you walk on it. Stopping the movement stops the noise.
Will glue alone work?
For a small gap, yes. Wide gaps and loose boards hold better with a glued shim or a screwed cleat.
This guide was drafted from the video's details and general task knowledge. It has not been checked against the full video. Check the video and relevant product instructions before following a procedure. Report a correction.
