i am planning on getting cushion floor for my bathroom. The tiler installed some stuff beneath the tiles as there were bare uneven floorboards with huge gaps underneath. My question is would I have to lift up the tiles and lay ply on top of the bare floorboards or can I use a self levelling compound on the tiles before getting the cushion floor installed?. I don't want the cushion floor laid directly on top of the tiles as the grout lines will undoubtedly show through and I know CF can be pretty unforgiving when it comes to what is under it. Thanks.