Cinder block wall preparation first the cinder or concrete masonry unit block needs to be prepared correctly.
Tiling over concrete block wall.
Tile cannot be attached directly to painted concrete as the thin set will not adhere well to the paint.
As for tiling on blockwork it can be done as long as its flat as a pancake every block is perfect then yes spread it on as u would a normal flat wall powdered addy but ive very rarly seen a perfectly flat blockwork wall in fact never.
You can get this from construction or hardware stores.
The safest way to approach questionable concrete is not to cover it over with cbus but to fix the concrete.
Ventilate and dehumidify the area before during and after the installation because basement walls are usually susceptible to moisture.
Id board it mate quicker and you can tile straight away.
Things you ll need ph neutral cleaner sponge scrub brush 3 4 expanded metal lath 1 1 2 or 2 inch concrete nails hammer tin snips thinset mortar bucket notched trowel ceramic tiles tile spacers plywood board carpenter s level silicone caulking grout grout float lint free cloth.
Any hairline structural cracks sprawling or gaping fissures or chips should be addressed.
For tiling over tiles in bathroom walls you ll need to set up sheets of waterproof membrane in between the concrete wall and tiles.
Installing tile over concrete walls is possible but presents some unique challenges.
The key to a long lasting and attractive tile installation is proper substrate preparation.
Cracks and gaps can be filled with portland cement based fillers.