Yes i know i'm on the wrong site but i think going by past experience there will be more of a light hearted response to my querey which is; 10 yrs ago i tiled my bathroom, not bad for a bricky, this time round i'm G.S.I. ( getting someone in) now he's given me a price, which is fine then i said i'll lift the floor tiles, his response was; if they are sound leave them down and he'll tile over them, they are sound even after 10 yrs, but the powers to be has decreed we have new tiles, i laid them straight onto the floorboards, 1930s house, so do i lift them or not??