Why tiles hollow after installation and the corresponding formulation and application solutions.
Hollowing of tiles is one of the most common failures on site. The main causes are poor substrate preparation, insufficient water retention of the adhesive, and incorrect open time.
Cause 1: Poor substrate preparation
Dusty or uneven substrates reduce adhesion. Clean and prime the substrate before applying the adhesive.
Cause 2: Insufficient water retention
When the adhesive loses water too quickly, the cement cannot hydrate properly. Using a suitable HPMC grade improves water retention and bond strength.
Cause 3: Exceeded open time
Applying tiles after the adhesive surface has skinned over leads to weak bonding. Adjust formulation and working method to keep the open time under control.