How to fix falling shower tiles on old drywall backing
Glues and mortars won't hold onto crumbling drywall or old mortar, and trying to cut out sections to retrofit cement board makes it nearly impossible to get new tiles to fit right. This leaves DIYers stuck between spending hours chipping away old material with a multi-tool or risking a wall that won't hold bonding surface.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Ripping everything out except the floor and installing new drywall everywhere except the shower area.
- 2scraping off only what is loose while leaving old mortar that is still tightly bonded
- 3pulling down all loose tiles to completely reinstall them
- 4mortaking loose tiles back into place temporarily until ready for a full renovation
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“Much of the tile in the shower area has already started to fall off, and since the backing is drywall, you really can't (and don't want to) reglue tile to it.”source ↗
“I initially attempted to cut out the drywall and install cement board and retrofit new tiles, but it's been a real pain with getting things to fit properly and with more tiles falling.”source ↗
“I'm wondering if I need to completely remove the old motor before applying new mortar and reattaching.”source ↗
“Will filling the gaps in the old mortar provide sufficient bonding surface for the tiles? Short of removing it with a multi-tool, it won't come off easily.”source ↗