Thinset Over Painted Floor

It must be easy to work with and it must adequately fill in gaps between the tile and the substrate.

Thinset over painted floor.

A scratch coat will give the mortar something to hold on to instead of the layer of paint over concrete. It cannot cure too fast. All paint will need to be removed before you begin installing the tile. Otherwise you do.

Paint used on concrete will not bond with the tile adhesive. Tile cannot be attached directly to painted concrete as the thin set will not adhere well to the paint. The floor is a 4 inch poured concrete slab over an unheated utility room. The polymer modified thin set mortars might bond to a latex paint but not an oil based paint.

The house was built in the late fifties and the slab floor has been painted at least once. Unfortunately the tile cannot be adhered directly to the painted surface. The safest way to approach questionable concrete is not to cover it over with cbus but to fix the concrete. Tile will stick to most rigid level surfaces including painted wood provided the correct preparation work is done to ensure the adhesive or mortar will stick to the floor surface.

Cracks and gaps can be filled with portland cement based fillers. First a surface more textured and solid must be applied over the painted concrete. Not that they would endorse going over an oil based paint what you should do is scarify the paint off the floor. Whether you have cracks chips or just a stained concrete slab thinset helps cover the old surface and create a new problem free area.

Mortar cannot be installed directly over painted concrete itself. How to use thinset morter to resurface concrete. Whether wall or floor tile that tile needs to thoroughly stick to its base surface demands placed on tile adhesive are both extensive and steep. This surface is called a scratch coat.