Why Large Format Tiles Fail (And It’s Not the Tile’s Fault)
Large format tiles have become the default choice for contemporary interiors. Clean lines. Fewer grout joints. Seamless surfaces. They dominate showrooms and Instagram feeds alike.
But here’s the uncomfortable truth:
When large format tiles fail, the tile is rarely the problem.
Cracked corners. Lippage. Hollow sounds. Debonding. Grout fractures. Edge chipping.
These are not “bad tile” issues.
They are specification and installation failures.
And the industry rarely says this clearly.
The Retail Narrative
Walk into most tile retailers and you’ll hear:
“They’re suitable for walls and floors.”
“Perfect for underfloor heating.”
“Rectified edges give a seamless look.”
“Just use a professional installer.”
Technically, none of that is wrong (except if your walls aren’t suitable to take the weight of large format tiles).
But it omits the real conversation:
Large format tiles demand tighter tolerances, better substrates, correct adhesives, proper levelling systems, and realistic expectations. They are not forgiving. And many projects are not prepared for that.
What Actually Happens on Site
Large format porcelain, typically 60x120cm and above, behaves very differently from smaller tiles.
1. Substrate Flatness Is Non-Negotiable
British Standard tolerances matter.
Floors and walls must meet strict flatness tolerances before installation. Even small undulations can cause:
Lippage
Rocking
Corner stress fractures
Adhesive voids
With a 30x60 tile, minor irregularities can be absorbed. With a 60x120 tile, they cannot. The larger the tile, the less forgiveness you get.
2. Adhesive Coverage Must Be Near 100%
Large format tiles require:
Correct trowel size
Back-buttering
Full adhesive contact
If voids remain beneath the tile:
Hollow spots develop
Impact cracks occur
Underfloor heating stress increases
Tiles may debond over time
This is not a tile defect. It is an installation method issue.
3. Rectified Edges Increase Risk
Rectified tiles are mechanically cut for precise edges. They look seamless. But precision means:
Tight grout joints
Higher visual sensitivity to lippage
Greater expectation of flatness
When installers attempt ultra-minimal grout joints on imperfect substrates, problems emerge. The tile didn’t fail. Tolerance did.
4. Underfloor Heating Adds Movement
Porcelain handles heat well.
But movement happens in:
Adhesive beds
Screeds
Expansion gaps
Structural transitions
Without:
Proper expansion joints
Correct adhesive flexibility
Correct curing time
Stress accumulates. Cracks appear. Again, not the tile’s fault.
The Commercial Implications
Who pays when large format installations go wrong?
Often:
The installer
The contractor
The retailer
Or the client
But rarely is the root cause identified correctly. Retailers sometimes blame:
“Bad batch”
“Transport damage”
“Manufacturing issue”
When the real cause is:
Improper substrate preparation or insufficient adhesive coverage. This is why large format tiles are frequently associated with disputes. Not because they are weak. Because they expose weaknesses elsewhere in the build.
When to Avoid Large Format Tiles
Large format porcelain is not always the right choice.
Avoid or reconsider when:
The substrate cannot be corrected to tolerance
Budget does not allow for levelling systems
Installer experience is limited
Rapid programme timelines restrict curing
Structural movement is expected
Smaller formats can be more forgiving and more commercially sensible in certain environments. Specification is about suitability — not trend.
What Professionals Do Differently
Experienced contractors approach large format tiles differently:
They measure flatness before ordering.
They factor levelling systems into the cost.
They specify flexible adhesives.
They plan movement joints.
They allow proper curing times.
They order correct batch quantities at once.
They treat the tile as a precision material, not a decorative afterthought. That’s the difference.
The Specification Reality
Large format porcelain is technically excellent.
It is dense.
It is durable.
It is dimensionally stable.
It performs well with underfloor heating.
But it demands:
Preparation
Planning
Tolerance control
Honest conversation before ordering
The failure risk is rarely in the porcelain. It is in the surrounding system.
We’ve seen projects where large format installations performed flawlessly for years. We’ve also seen installations where cracking occurred within weeks. The difference was almost never the tile. It was preparation.
If you’re considering large format porcelain for a project in London or the surrounding areas, we recommend reviewing:
Substrate condition
Installer capability
Movement allowance
Adhesive specification
Batch planning
We specialise in preventing expensive tile mistakes before they happen. If you’d like a specification check before ordering, contact our team prior to installation.