I am attempting to seal gaps and cracks in an apartment kitchen. Upon inspection of the sink area I noticed a void approx. 6" wide between the cabinet beneath the sink and the adjacent (tiled) wall. I was able to remove a fascia piece from the cabinet in order to get some pictures inside which revealed a 1-2" gap where the drywall simply ends short of the corner. This gap is exists from the floor up to the sill height. I want to fill in this gap effectively to prevent pests. The end result doesn't need to be seamless but should be possible to paint, i.e. no unfinished drywall or foam which can harbor mildew etc.

Photo of gap at cabinet wall

The ideas so far:

A: The building super's solution was to board up around the countertop and cabinets so that you couldn't see the gap and debris couldn't accidentally fall in which doesn't really solve the issue of pests being able to enter/exit through the wall.

B: The next thing proposed was to use spray foam such as Great Stuff Big Gap Filler. This is quick and easy to do however it would have to be done in one shot and cleanup afterwards would be impractical. If going this route, I would like to have a board or other flat surface for the foam to set against instead of spilling out of the gap.

C: Patch with joint compound, repair fabric, or cut drywall. This seems difficult with the limited access (I am told the cabinet must not be removed) and I am unsure if a backing material would be necessary.

D: Simply use a large corner bead such as this 2-1/2" one sold by Home Depot. One side would need to be affixed to existing tile, the other would hopefully cover the entire gap distance on the drywall side. Might need additional backing material?

I have read similar questions on this site (ex: How do I fix a hole/gap between my shower tile and the dry wall next to it? and How to finish wide gap in drywall at edge of ceiling) which offer very suggestions similar to C & D. However limited access is my main constraint, so it is not clear whether these options are effective if I am unable to cut a drywall patch or cleanly caulk the corner seam.

In summary, given the situation are any of B, C, or D obviously a better solution? What gotchas should I be aware of and how can they be accounted for?

  • See if you can find a chunk of mineral wool. Stuff it piece-meal into the gap to close it. Let the super board up the opening so you can't see it. The mineral wool won't make a sticky mess and should do a decent job blocking pests or drafts. If it's a rented apartment, it's not yours to make a personal project out of. Getting the super to do a better job fixing it is a different story. Commented Sep 19, 2023 at 16:21
  • Why are you against expanding foam? Clean-up seems irrelevant as this is hidden, and foam won't "harbor mildew" any more than the wood and drywall that's already there. This seems like exactly what expanding foam was designed to address... Commented Sep 20, 2023 at 13:34
  • In several areas where I've used foam in this area it became a nesting spot for fly larvae which was a surprise to me but has made me at least wary of using it without a second thought. Though outside the main scope of this question, the top floor where this is has leak issues (parapet needs full replacement, windows, etc.) during heavy storms and so I am likely to leave the area open for ventilation, even if it is out of sight. Mineral wool should be doable without a terrible amount of effort.
    – ics
    Commented Sep 21, 2023 at 14:09

1 Answer 1


D seems best of the options, but yet seems flimsy to work with.

Option E: Based on the spec'd 1-2" gap, I would try a 3-to-4-inch-wide board of correct length, scribed and pre-fit if possible to ensure the board will fit any curves in the wall correctly. Pre-drill a few screw holes in the board so screws can attach the board to the drywall if screwed in gently.

Cover one face and the side of the board with construction adhesive. Push the board into the corner against the back wall and use another board of suitable width to press the board over to the tile so the adhesive glues the board to both the back wall and the tile. Screw through the pre-drilled holes into the drywall lightly, just to tack the board in place while the adhesive dries.

Paint if desired, replace the cabinet CT and filler, and holes are plugged.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.