Toilet Floor: Ply & Lino Replacing Tiles: How Thick Ply? Insulation?

[Lord Snooty]

I'm replacing the tiles in the downstairs toilet with ply and lino. It's a concrete floor, what's the thinnest ply I can use? Also is it worth using some sort of membrane insulation under the ply (there's no heating).

Thanks,

 

[blup]

Should be ok if the concrete is dry level and free from damp.

An underlay can help keep the ply and floor covering level, or you could try self levelling compound.

Blup