The adhesive does not stick to the substrate
CAUSES
1. The substrate has not been thoroughly cleaned (carries dust, oil, etc.)
2. The substrate has been treated with special non-absorbent materials prior to application of the adhesive.
3. Do not use the correct type of adhesive for the particular substrate (consult the guide at the end of the glue guideline and apply each one).
4. The glue is very tight.
5. The substrate is moist or there is moisture in it.
• All the above apply also to the tile that is to be applied.