If your wall is painted, you should prepare the surface before installing the concrete panels to ensure a durable and safe attachment. Here's what you can do: 1. Remove the paint: If the wall is covered with paint, it is recommended to remove it, especially in the case of paint on cement-lime plaster. Removing the paint will allow the adhesive to adhere better to the wall. 2. Alternative - GK or OSB boards: If you do not want to remove the paint, you can prepare the surface by:
Attaching GK (plasterboard) or OSB boards to the wall.
The boards should be glued, drilled and fixed with dowels and screws so that they are firmly attached to the wall.
Then, a primer is applied to the prepared surface and only then the adhesive for installing concrete panels.
3. Applying the primer: A dedicated primer should be applied to the cleaned or prepared surface (e.g. GK or OSB boards), which will increase the adhesion of the adhesive and ensure the durability of the installation.