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Is your shower failing, or just ugly?
How to tell cracked grout from a waterproofing failure — and which one means the whole thing comes out.
Cracked grout in a shower is one of those things that looks alarming and often is not, and occasionally looks minor and is very much not. The difference matters, because one of them is a tidy afternoon and the other means the tile comes off the wall.
Cracks that are usually not a failure
Look at where the crack is. A clean, straight line of cracked grout exactly in the internal corner where two walls meet, or in the corner where the wall meets the floor of the pan, is very common. Those changes of plane are supposed to have a flexible joint in them rather than rigid grout, because the two surfaces move independently. When somebody grouted straight through, the grout is doing a job it was never able to do and it cracks along that line.
That is a finish problem, not a waterproofing problem, assuming it is caught before water has been running through it for a long time. Rake it out, put a proper flexible joint in, and it stops coming back.
Cracks that worry me
- Cracking out in the middle of a tiled field rather than in a corner.
- Tile that sounds hollow when you tap it, or that has any movement at all.
- A musty smell that does not go away when the room is dry and ventilated.
- A stain or soft spot appearing on the other side of the shower wall, or on a ceiling below it.
- Grout you have already repaired once that has cracked in the same place again.
Those suggest movement behind the tile or water getting past the surface. Grout is not waterproofing — it never was. The waterproofing lives behind the tile, and once that is compromised, regrouting the front of it just hides the evidence for a while.
A two-minute check you can do yourself
Dry the shower out completely, then go over the walls with your knuckles, tapping lightly. Tile that is properly bonded sounds solid and consistent. Tile with a void behind it sounds hollow and noticeably different, and you will hear the change immediately once you have heard both.
Then press firmly on any tile around the cracks. Nothing should move, flex or click. If it does, stop poking it and get somebody to look at it.
Repair or rebuild
If it is corner cracking, the tile is solid everywhere, and there is no smell or staining, that is a repair. Rake out the failed grout, put the flexible joint where it should have been, and you are done in a fraction of the time a rebuild takes, with no demolition and no dust through the house.
If tile is drumming, moving, or there is any sign of water where water should not be, the honest answer is that it needs opening up. I know that is not the answer anybody wants. But the alternative is paying for a repair, watching it fail again in a year, and then paying for the rebuild anyway with more damage behind it than there is today.
I will tell you which of the two it is when I look at it, and I will tell you if it is the cheap answer. Talking somebody into a tear-out they did not need is a good way to never get called again.
Related: Tile Work
More from the blog
- How I price a job, and why I won't guess over the phone
- The new-build punch list your builder never came back for
- Before you call anyone: the photos to send
- One visit or three? How to group a punch list
- Drywall cracks: which ones matter and which ones don't
- Why a texture repair shows, and how matching actually works
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- Gutters: what they are actually protecting, and when to clean them
- After a Texas storm: what to check, and in what order
- Cabinets: reface, repaint, or replace?
- Interior painting: the preparation is the job
- Building outdoors in this sun: what actually lasts
Ready to get that list handled?
Send a few photos and I'll tell you what it takes. Free written estimates across Leander, Cedar Park, Georgetown, Round Rock and the towns nearby.