A scratch coat will give the mortar something to hold on to instead of the layer of paint over concrete.
Tile over painted concrete walls.
Mortar cannot be installed directly over painted concrete itself.
For application over an uneven concrete surface a lightweight waterproof construction board.
Water should readily absorb in the concrete as an indication that it is suitable for bonding the tile to it.
Rent a circular concrete sander from an equipment rental store.
Tile cannot be attached directly to painted concrete as the thin set will not adhere well to the paint.
Before beginning a tile installation over a concrete wall perform an inspection to look.
If the walls you want to tile are concrete walls with paint on them remove the paint before you install tile so the tile adhesive has something to grab onto and hold the tile in the correct place.
If the paint comes loose so does the tile.
Using the sander will generate a lot of dust.
Painted concrete can be made porous with sandblasting or other hard abrasive actions.
How to install tile on a painted concrete floor step 1.
Inspect the concrete surface.
Can i put tiles over painted concrete walls.
Go back over any spots that have remaining paint with your.
First a surface more textured and solid must be applied over the painted concrete.
If you choose to try to bond the tile to the paint then you need determine what type of paint it is.
A latex based thin set adhesive should be used over the latex based paint.
Vacuum up all loose dust debris and paint residue.
An epoxy based paint requires an epoxy adhesive to bond to it.
You should either strip or bead blast the concrete and thoroughly clean it.
Ventilate and dehumidify the area before during and after the installation because basement walls are usually susceptible to moisture.
You can leave the paint on drywall provided there are not several coats and the tile epoxy will adhere with no problem.
While you can install tile directly on concrete problems erupt when the concrete cracks or shifts.