Brian Hay
Hi, Yes, they should be removed first as if the tiles or adhesive underneath them fail then they will fail whatever is on top of them as well ie; your new self leveller and flooring on top. What is your subfloor concrete/wood? What is the new floorcovering you are putting down? Have you checked for damp? How old is the house? Are you trying to level or smooth the floor? Cheers Brian Scotflooring.co.uk
