Fixing a Squeaky Stair From the Underside

If you have access to the underside of your staircase, these repair options will be hidden solutions to squeaks. Select the option that best fits your needs and situation. Always wear protective goggles for these tasks.

Option 1:
If there is play between a stair and the riser behind it, this may be your best solution. Coat small wood shims with wood glue and tap them into the gaps between the underside of the affected stair and the adjacent risers. Wedge the shims until they feel snug, but don’t force them or you may widen gaps.

Option 2:
If you think the cause may be warping, installing brackets may be just what you need. From the underside, drill pilot holes that will snugly accommodate round-head wood screws. Make sure the screws are about ¼ inch shorter than the depth of the stair, or they’ll pierce through the top. Mount a fender washer on each screw and install shelf brackets to provide support.

Option 3:
Glue or tape two support blocks to the front underside corner where the stair meets the backside of the riser. Drill one pilot hole through each block into the stair above and then two holes into the riser in front (3 holes in each block). Make sure the wood screws you use are ¼ inch shorter than the combined depth of the wood block and the stair or riser, or they will poke through. Screw the blocks place.

You can also take a look at how to fix a squeaky stair at stair level.

Having a tough time with those squeaky stairs? Talk to others who suffer from squeaky stairs in our Floors and Stairs forum to get help.