What Goes Wrong with Tiles and How to Avoid Costly Mistakes Before They Happen

Introduction

Tiling projects often fail not because of the tiles themselves, but because of avoidable specification and preparation errors. From improper substrate prep to incorrect material choices, these mistakes cost time, money and reputation. This blog identifies the most common failure points and shows how to eliminate risk before work begins.

Technical Breakdown: The Real Causes Behind Tile Failures

1. Substrate Preparation Errors

Tiles cannot perform without a stable base. Common issues include:

• Unlevel screeds and uneven floors — leads to lippage and early grout failure.

• Poor moisture barriers — allows rising damp and blisters beneath tiles.

• Inadequate surface roughness — means adhesives don’t bond properly.

✔ What to specify:

• FF (floor flatness) tolerances in the contract.

• A damp proof membrane (DPM) where required.

• Appropriate levelling compounds per BS 5385.

2. Wrong Tile Choice for the Application

Too often tiles are chosen on look alone. This leads to:

• Bowing or cracking in commercial/high traffic zones.

• Staining or surface dullness in wet areas.

• Unsuitable slip performance.

✔ What to check:

• Use PEI ratings for wear suitability.

• Match R-rating to room use (e.g., R10+ for wet interiors).

• Avoid low-rated tiles under heavy load or water exposure.

3. Incorrect Adhesive and Grout Selection

Not all adhesives and grouts are equal. Get this wrong and you’ll see de-bonding and staining.

• Flexible adhesives are essential for tiles > 300×600.

• Heated floors require heat-rated adhesives/grouts (also flexible).

• Mosaics often need epoxy grouts to minimise staining.

✔ What to specify:

• C2S1 or C2TES1 adhesives for most porcelain.

• Grouts compatible with wall/wet areas.

• Always follow manufacturer instructions.

4. Thermal and Structural Movement Ignored

Buildings move. Materials expand/contract with temperature and moisture changes.

• Lack of movement joints → cracking and edge failures.

• Improper joint placement around frames → stress points.

✔ What to plan:

• Follow BS 5385 and movement joint guidelines.

• Integrate expansion zones into layouts early.

Commercial Implications of These Mistakes

Time Cost

Rework means delays. What should have been a few days becomes weeks.

Monetary Cost

Labour and materials double up when re-tiling or fixing failures. Clients often don’t budget for it.

Liability & Reputation

Repeated failure points damage trust and can cost repeat business, particularly in trade.

Practical Recommendations (What You Should Do)

• Request pre-site surveys before tile ordering.

• Order samples to confirm looks and performance.

• Include substrate and movement planning in specifications.

• Provide installers with BS 5385 guidance notes.

• Confirm adhesive/grout specs before signing off.

When to Avoid This Option

Despite their durability, tiles aren’t always the right fit:

• High vibration floors (without proper decoupling)

• Poorly detailed wet rooms without waterproof zones

• Historic floors with soft substrates

If these conditions apply, consult a structural or wet-room specialist before specifying tiles.

For specification support, trade account details or sample dispatch, contact our technical team — and avoid costly mistakes before they start.