Typical signs
- Cracked grout, hollow or moving tile, detached silicone or persistent staining.
- A joint that reopens after a local repair.
Where it is often found
- Showers, tubs, backsplashes, tile floors, thresholds and corners.
What it can mean
- Substrate movement, insufficient adhesive coverage or missing movement joint.
- Damaged membrane or water intrusion in a wet area.
What to check next
- Gently test stability without pulling tile off.
- Check moisture, slope, perimeter joints and adjacent rooms.
Reasonable immediate actions
- Stop using a shower if water is likely reaching the substrate.
When to stop and call a professional
- Multiple loose tiles, soft substrate, odour, mould or membrane replacement.
Prevention
- Rigid substrate, continuous membrane, movement joints and maintained flexible sealant.