Continue placing the first course of tiles in the same manner using spacers.
Tile over painted concrete block wall.
Mortar cannot be installed directly over painted concrete itself.
Place strips of blue painter s tape over the tile face sticking each end to the wall to prevent the tiles from sliding.
If your wall is freestanding with a top tile the center of the top area with the same tile that you chose for the sides of the wall but use bullnose tiles all around the top edges.
First a surface more textured and solid must be applied over the painted concrete.
Hammer the nails through.
Inspect the concrete surface.
For application over an uneven concrete surface a lightweight waterproof construction board.
Painted concrete can be made porous with sandblasting or other hard abrasive actions.
Clean the surface of any dirt or debris with a ph neutral cleanser and a sponge or scrub brush.
With a notched trowel apply the adhesive at the bottom of the cinder block wall.
This surface is called a scratch coat.
You should either strip or bead blast the concrete and thoroughly clean it.
Nail 3 4 expanded metal lath to the blocks with 1 1 2 to 2 inch concrete nails.
A scratch coat will give the mortar something to hold on to instead of the layer of paint over concrete.
Answer answer it is possible to bond porcelain tile to a painted surface but it isn t recommended because the overall tile attachment is limited to the strength of the bond of the paint to the concrete.
If the paint comes loose so does the tile.
While you can install tile directly on concrete problems erupt when the concrete cracks or shifts.
How to install ceramic tile over painted block walls for a shower step 1.
Apply just enough of the adhesive to attach a few tiles at a time so that the adhesive stays moist and ready to receive the tiles.
Tile cannot be attached directly to painted concrete as the thin set will not adhere well to the paint.