DIY Doctor UK DIY Forums

I have a plumber fitting an en-suite and the floor is not level. He has covered the boards with ply and wants to put expanding foam under the stone resin tray to level it off. My husband thinks he should be using cement as the foam may not last and cause movement of the shower enclosure with the wall.
Has anybody got any comments on the use of expanding foam for this purpose please?? :?

No worries with foam it will last every bit as long, if not longer than sand and cement.

doctor, would you have to let the foam go 'off' slightly before you place the shower tray on it, as I would have thought the tray would sink under its own weight.