Tile movement
A loose or poorly bonded tile can crush or separate the grout around it.
Tile repair guide
How do you repair cracked grout or loose tile?
Cracked grout is sometimes a simple material failure, but it can also be the warning sign that the tile or subfloor is moving. MAPEI’s grout troubleshooting guidance specifically lists movement, poor tile bond and subfloor deflection among causes of recurring grout cracks.
That means the first question is not “what color grout do I buy?” It is “is the tile still solid?” A firm tile with a localized grout defect can often be cleaned out and regrouted. A loose or hollow-moving tile needs its bond corrected first.
The short answer
If the tile is solid, remove loose grout to sound material and regrout the joint. If the tile moves, clicks or has lost bond, remove and reset the tile before regrouting. At changes of plane and designated movement joints, use the appropriate flexible sealant rather than rigid grout.
What cracked grout means
Common reasons the joint failed
A good grout repair depends on why the original joint cracked.
Subfloor deflection
Too much movement in the floor system can repeatedly crack rigid tile assemblies.
Wrong grout or mix
Joint width, excess water and mixing technique affect grout performance.
Grouting too early
Setting material needs proper cure before grout locks the installation together.
No movement joint
Rigid grout at changes of plane or required movement locations can crack.
Incomplete joint
Shallow or poorly packed grout has less material to resist normal service.
Repair method
How cracked grout and loose tile are repaired
Do not regrout until the tile is stable.
Test the tile
Check for movement, rocking, surrounding cracks and signs of water or substrate damage.
Remove failed material
Cut out loose grout without chipping tile edges. If the tile is loose, remove it carefully.
Restore the bond
Clean the substrate and tile, correct the underlying issue and reset loose tile with compatible setting material.
Regrout or seal
Use the correct grout in stable joints and a flexible sealant where movement is expected or required.
What repair belongs where?
Grout, reset or flexible joint
These are three different repairs.
Regrout when…
- The tile is firmly bonded.
- Cracking is localized.
- The substrate is stable.
- The joint is supposed to be grouted.
Reset tile when…
- The tile rocks or moves.
- Bond has released.
- Mortar coverage is poor.
- The tile can be removed without destroying the surrounding work.
Use flexible sealant when…
- At changes of plane where appropriate.
- At movement or expansion joints.
- The tile system calls for a flexible joint.
- Rigid grout has repeatedly cracked because the joint moves.
Frequently asked questions
Common questions about this repair
Can I put new grout over cracked grout?
Not as a durable repair. Remove loose or failed grout to sound material so the new grout can properly fill and bond within the joint.
Why does the grout crack again after I repair it?
Recurring cracks often mean movement was not corrected. Loose tile, subfloor deflection, missing movement joints or the wrong material at a change of plane are common causes.
Can a loose tile be fixed without removing it?
There are specialty injection methods for some installations, but a conventional repair usually involves removing and resetting the loose tile so the bond and substrate can be inspected.
Should corners in a tile shower be grouted or caulked?
Changes of plane are commonly treated as movement joints and typically use an appropriate flexible sealant rather than rigid grout. Follow the tile-system and product requirements for the installation.
Need help with the repair?
Send VPS the problem and a few photos.
Virginia Pro Services handles residential repair and finish work throughout Hampton Roads. A clear description and photos are usually the fastest way to start.
This guide is general homeowner information. Hidden damage, structural conditions, local permit requirements and regulated trade work can change the proper repair approach.