Before paying
Raise concerns immediately and ask the tiler to address them. Good tilers stand behind their work.
Introduction
Bad tiling is everywhere - and most homeowners do not realise they have a problem until tiles start cracking, grout begins falling out, or water damage becomes visible behind the walls.
Knowing the signs of bad tiling work before you pay your final invoice - or before you buy a home with problem tiles - can save you thousands. This guide explains exactly what to look for and what each sign means.
Why Bad Tiling Is So Common
Tiling looks deceptively simple. Many people underestimate the skill required, which means the market is full of less experienced tilers charging professional rates.
The real damage from bad tiling is often hidden. Inadequate waterproofing, poor adhesive coverage, and incorrect surface preparation all create problems that may take months or even years to become visible.
Signs of Bad Tiling Work
1. Hollow Tiles (The "Tock" Sound)
Walk slowly across a tiled floor and knock firmly on the surface as you go. A healthy tile should make a solid "thud" - an indication the adhesive behind it is making full contact with the substrate.
A hollow "tock" or "clack" sound means there is an air gap beneath the tile. This can mean:
- Adhesive was applied in small blobs (spot bonding) instead of full coverage
- Adhesive dried before the tile was pressed into it
- The substrate is hollow or failing beneath the tile
- The wrong grout was used for the joint width or application
- The adhesive had not cured fully before grouting
- No expansion joints were left at the perimeter - the floor has no room to move
- There is movement in the substrate beneath the tiles
Hollow tiles are a serious problem. They crack under load and will eventually fail. On walls, they can fall off.
How serious: Very. Hollow tiles usually mean the affected tiles need to be removed and re - laid.
2. Uneven Tile Surfaces (Lippage)
Run your hand or foot across a tiled floor or wall. Every tile surface should be flush with its neighbours. If you can feel a step or ridge where one tile sits higher than the next, this is called lippage.
Some lippage is unavoidable with certain tile types (handmade or natural stone tiles have more natural variation), but machine - made ceramic and porcelain tiles should be laid with minimal lippage.
More than 1 - 2mm of lippage on a flat floor is a sign of poor workmanship.
How serious: Moderate to serious. Pronounced lippage on floors is a tripping hazard and is uncomfortable underfoot. Correcting it usually requires removing and re - laying the affected tiles.
3. Cracked Grout
Grout that cracks within the first year of installation is a sign that:
Some minor surface cracking in very wide grout joints can be normal, but cracks that run through the full depth of the grout joint or that reappear after being repaired indicate an underlying problem.
How serious: Moderate. Cracked grout allows water to enter in wet areas, which can cause adhesive failure and water damage. It needs to be addressed, especially in bathrooms and showers.
4. Uneven Grout Lines
Stand back and look at the tile pattern from a slight angle. The joints between tiles should be consistent in width throughout. If grout lines are obviously wider in some places than others, or if tiles are clearly not aligned in straight rows, this is a sign of poor planning and poor execution.
How serious: Cosmetic, but a clear indicator of the overall quality of the work.
5. Grout That Is Poorly Filled
Grout lines should be fully packed - filled flush with the tile surface or very slightly recessed. Grout that is only partially filling the joints, or that has gaps and pinholes, has been applied poorly.
Partially filled grout joints collect dirt, allow water ingress, and look unsightly.
How serious: Moderate. Can be repaired by raking out and re - grouting, but it is a warning sign of rushed work overall.
6. Missing or Incorrect Expansion Joints
All tiled floors need a gap around the perimeter where the tiles meet the walls or skirting boards. This gap should be filled with flexible silicone - not grout. If grout is packed hard against the wall with no expansion allowance, the floor has no room for natural movement.
The result: cracking tiles and grout near the edges of the room.
How serious: Moderate to serious. A common problem that causes visible cracking over time.
7. Silicone Applied Over Dirty or Wet Surfaces
Silicone sealant applied over dirty, damp, or poorly prepared surfaces will peel, crack, or separate within months. Good silicone work requires clean, dry, primed surfaces.
Peeling silicone in a shower is particularly problematic - it is the first line of defence against water getting behind the tiles.
How serious: Moderate. Peeling silicone in wet areas must be replaced promptly.
8. Tiles That Are Not Level
On walls, tiles that are not level are immediately visible. Stand back and look horizontally across the wall - the top edges of tiles should form a consistent horizontal line. If they slope noticeably up or down, the tiler did not use a proper level.
How serious: Cosmetic, but very visible. Correcting it requires removing and re - laying affected tiles.
9. Poor Cuts and Rough Edges
Cuts around pipes, door frames, and edges should be clean and neat. Rough, jagged cuts, large gaps covered with excessive silicone, or poorly fitted edge pieces are signs of inadequate cutting technique or cutting tools.
How serious: Cosmetic and practical. Poor cuts around plumbing penetrations can allow water ingress.
10. Tiles Laid Over an Unprepared or Unsuitable Surface
If tiles are cracking in a pattern that follows structural lines (a diagonal line across several tiles), or if tiles are lifting in one area while fine in another, the surface preparation may have been inadequate.
Tiles laid over cracked plaster, hollow substrate, or an incompatible surface will fail systematically.
How serious: Very serious. The cause needs to be identified - in some cases all tiles in the area need to come up and the surface prepared properly before re - tiling.
What to Do If You Spot These Signs
After paying
Document everything with photos. Get a second opinion from another professional tiler.
Buying a property
If you see these signs during a viewing, factor the cost of remediation into your offer.
Practical Advice
- Do a tap - test on any tiled surface before accepting the work
- Walk the floor yourself - uneven tiles are easy to feel underfoot
- Check grout lines from multiple angles and distances
- Check that silicone has been applied at all floor - wall junctions in wet areas
- Ask the tiler to show you where they applied waterproofing before the tiles went on
Conclusion
Bad tiling signs include hollow tiles, lippage, cracked grout, uneven lines, missing expansion joints, and poor cuts. Many of these problems are hidden at first and become expensive later.
Knowing what to look for - and checking before you make final payment - is the best protection against costly repairs.
Ready to start your project?
Want tiling work you can trust and inspect with confidence? Contact Excellence Tilers in Cape Town. We welcome client inspections during and after our work - because we are confident in the quality of every job we do.