While patching my kitchen ceiling, I cut the hole larger to get to the joists and install my drywall "normally". On one of my edges the old drywall keeps crumbling away. My plan is to make the hole bigger still and toenail in some furring (a board to screw the patch to). However, every time I breathe near this edge it seems to crumble more. The original drywall is probably 30 years old. How do I keep this patch from growing?

The edge on the left is what keeps crumbling away. enter image description here

  • 2
    Is it drywall (with a paper covering) or plaster?
    – BMitch
    Commented Sep 23, 2011 at 11:44
  • @BMitch - all drywall. The plaster between the paper is what keeps crumbling away. Commented Sep 23, 2011 at 11:48

2 Answers 2


Sounds like a bad spot in the drywall, maybe caused by water damage, or physical abuse. You're probably best to keep cutting until you find a good section, though you may get away with simply taping and mudding the joint. The tape should hold the section together, so even if the plaster is crumbling it will be held in place. If you opt to just tape and mud, there is no guarantee you won't develop a crack in the future.

If it were me, I would keep cutting (at least to the next joist). If you're lucky the bad section will not extend that far, or at the very least won't extend farther than a full sheet of drywall. You could try to patch it with compound, but it's not likely you'll be happy with the results.

  • This too - definitely use tape and mud after you get a clean cut. Commented Sep 23, 2011 at 12:47

Fight fire with fire - cut a clean sharp line a distance around the damaged area, then patch.

A multi tool like the one below, using a tile or wood cutting attachment (round not square) will allow you to cut a nice, crisp clean line. Much cleaner and with less vibration impact than even using a hand drywall saw in my experience.

enter image description here

  • I prefer a razor knife. Might take a bit longer, but is much cheaper, less messy, and quieter.
    – Tester101
    Commented Sep 23, 2011 at 14:51
  • 1
    Cheaper and quieter yes. Less messy - not so much. The vibrating blade doesn't spew dust. And being a long blade helps you keep the line straight. Plus - it's a power tool! ;) Commented Sep 23, 2011 at 14:52

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.