Is this shower tray ok to sit just on the 400mm spaced floor joists or will it need ply under it?
Hello,
It has be underboarded, but by proper installation you can effective make it sit on the joists. Please see our fitting instructions, they describe it well:
https://wetroomsdesign.co.uk/wet-room-kit-shower-tray-installation-instructions-timber-floor
I am happy to help if you have any questions.
Kind regards
David M.
020 7193 0953