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Do the straps hold onto tiles?
Yes, there are possibilities here as well.
Tiles often have a very smooth surface and the glue can not penetrate and adhere properly, therefore, the tiles must be pre-treated accordingly:
1. Basic cleaning of the tiles of all contaminants and surface coatings with e.g. solvent
2. Generous sanding of tiles with e.g. abrasive paper This sanding roughens the surface and gives the adhesive a better adhesion to, for example, glazed tiles.