Widespread Cracking with a Polygonal Development

Defect visualisation

Complete or very extensive cracking of the flooring. The cracks form irregular polygons of broken lines with a random development, though they usually converge at particular points.

In a first phase the malfunction is only visible (in glossy floorings with tangential light) as a slight convex curvature in given areas, delimited by subtle irregular lines. In a second phase, the lines constitute true cracks that will hold dirt and become visible even with little lighting.

In ceramic floorings with GL tiles, the glazes and engobes may shiver in sawtooth form in certain areas of the cracks.

This malfunction has exhibited itself in every type of flooring, even terrazzo, and in small surfaces (less than 16 m²).

2^nd Phase

1^st phase: Convex curvature of the flooring between lines that display irregular polygons
2^nd phase: Crack width increases and the cracks complete their polygonal development. In GL ceramic tiles, glaze shivering may occur.

Other inspection data

When the defect is approached, after pulling up and extracting tiles it is found:

• That the cracks affect the entire thickness of the tile (the tiles are already broken)
• That the geometry of the crack is reproduced like a tracing on the bonding material (mortar or adhesive) and fixing surface
• That the flooring usually does not sound hollow and that the tiles are securely adhered

The meeting of the flooring with the skirting or wall tiling does not display any cracks in the joint at the change of plane, or sinking, or curvatures.

In addition, this malfunction has a variable evolution in time which recalls the appearance of delayed crazing in glazed tiles. The malfunction may appear a few weeks after the tile installation, as well as after several months.

• Assignment of the malfunction
  

• Prevention of the malfunction
  

• Historical

• How can we resolve the malfunction?