O
Old Mod
Why would the op do that? It's all brand new studwork and boarding.Fill the walls out with tiling addy and as for the 3mm rise between floor and tray, youll take that out with tiling addy aswell
There's no excuse for it to be like that at all!
Should be made to start again. And do it correctly.
And parts would fall beyond sensible capabilities of adhesive, and it's not good practise anyway.
Whether or not it actually works, it'd also void any guarantee from adhesive manufacturers.
And there is the little matter of it being a wetroom, not 3 high around a bath.