I've never heard of any 6mm floor gypsum, actually. Do you know if it exists at all? I'm pretty sure Gyproc doesn't have it in their range anyway.
Hmmm, searched but found nothing. Also visited Gyproc's, Danogips's, and Norgips's websites, and no 6mm floorboards as far as the eye could see. But why wouldn't it work with a regular 6mm wallboard ("renoveringsgips")? It sounds like it's stable enough...
Wall plaster is not reinforced in the same way and will certainly become exhausted if installed on a floor. I haven't seen 6mm floor plaster anywhere either.
But why not pour a thin layer with reinforced leveling compound, I think it works down to 5 mm. Or add a bit more concrete and lay the stone directly in it.
But why not pour a thin layer with reinforced leveling compound, I think it works down to 5 mm. Or add a bit more concrete and lay the stone directly in it.
I have had 6 millimeters of ROT gypsum now under my pebble floor in the hallway for almost two years, and it hasn't cracked at all in the joints. The only thing that has cracked is around the walls where the floor/wall have moved in relation to each other.
Surface gypsum, renovation gypsum, dear (?) child has many names.