- Absence of joints necessary for the movement of the system (desolidarization, movement and structural);

 

- Absence of roughcast not giving the necessary adhesion to the laying mortar anchoring;

 

- Lack of adherence of the laying mortar itself for various reasons, such as excess water in the mass, reuse of previously prepared mass, application of mortar with the open time already exceeded, etc.;

 

- Absence of grouting (even in Dry Joint);

 

- Existence of infiltration or moisture;

 

- Absence of double gluing on tiles over 30 × 30 cm;

 

- Irregular base, with dirt, loose layers, uneven, etc.