Do I have to prepare/smooth the processing ground?

In order to glue Slate-Lite optimally the substrate must only be smooth, dust-free, clean and not moist.

Crumbling substrates such as old, crumbling plaster or wallpaper that is already slightly loose must be primed in advance to ensure the permanent connection of glue to the wall.

No special preparation is necessary for "stable" substrates.
Too strong unevenness on the application surface must either be worked with a primer or sanded smooth.