Happy New Year everyone! Just wanted to check the feasibility on a shower room floor prep. A customer has asked me to tile (walls & floor) in an ensuite shower room. She is quite uneasy on her feet so wants the transition between the bedroom carpet & the ensuite tiled floor to be as level as poss. The room is literally a shell at the mo. Would it be standard practice to board between the joists with 18mm marine ply to enable a level threshold. I would then intend to lay 10mm Jackoboard, UFH cable, SLC & an 8-10mm porcelain floor tile. Any input gratefully received.