How to Answer Tile Complaints about Cracks & Lippage.

Complaint: There are small cracks on the edges of the tiles.

Problem:
Sometimes a fault occurs in manufacturing that causes what appears to be a crack in the glaze, normallty at the edge of the tile. This is a firing crack. It is caused by uneven expansion and contraction.  Generally, these tiles are removed during sorting and grading and sometimes when tiles are cut to exact size (rectification). Sometimes a faulted tile does slip through. These should not be installed. The unmarked area of the tile is fine and should be using as a cut tile, but the damaged glaze makes it unsuitable for a whole tile to be laid. A tiler should put any tile with a visible fault like this to one side and use it for a cut tile when needed.
 
What do I say to the customer?
These tiles will be exchanged or credited by the Retailer where they were purchased from. If a few imperfect tiles have been laid, especially with firing cracks, they should be replaced by the tiler before the job is finished. Faulted tiles must not be laid. Every single tile should be inspected for faults by the tiler.



Complaint: The edges and joints of the tiles are uneven.

Problem: 
An uneven surface, different thicknesses of grouting, irregularities. A good, professional tile laying project will ensure that all the joints are even and the edges of each tile are level. When two tiles are not level and the edge of one is higher than the next, it is referred to as lippage. You can see a good example in the photograph above. This is inevitably the fault of the tiler not the tile. Although tiles may vary fractionally in thickness it is very rare for the thickness to exceed the international standards. If a tiler leaves the project with tile lippage, he should be prepared to come back and fix them fix them.
 
Cause:
Lippage can occur if the tiler sets large or heavy tiles into a thick bed of adhesive and the tile settles or slumps unevenly into the adhesive. There are special adhesives available for these large format tiles that will minimize this issue. If a tile is not quite flat, extra care must be taken when laying to avoid lipping. There are standards within ceramic manufacturing that allow for a certain amount of curvature across a tile, variation in tile thickness, straightness and size. Only tiles that satisfy the standard will be sold as first grade and these can be laid without any lipping or noticeable faults.
 
What do I say to the customer?
If the finished tiled floor has uneven grout joints, or lippage on the edges of tiles, you should point out that the cause is the skill or lack thereof of the tiler and recommend that the customer should talk to the tiler or builder about rectification. Lippage is a safety risk as people can trip. Also, where the surface of a floor between tiles is uneven, it is likely that the tiles will chip. This is especially the case if heavy furniture is dragged across the uneven edge. Tiles will last a long time if they are laid flat and even with even grout joints.