That’s a bit unfortunate but, personally, I’d space the PB off the floor by 12mm & put another strip in the top.1. Do i fill the gap with adhesive and tile OR make this bottom gap smaller by adding another strip of plasterboard (maybe 100mm) making sure not to go flush down on the floor. This giving some support to bottom row of tiles?
Unless your tight for space do it as you say fit the backer board then shower tray, then tile up from that; leave a 2mm gap between the tray & the 1st tile for silicone seal.2. Does the hardibacker/aquapanel go down to the floor THEN the shower tray (45mm deep) butted up against before tiling?
15mm is too much to space off with D&D; either chase the wall for the pipes or use timber battens.3. Is it do'able to dot dab hardibacker + thru frame fixings whilst still have enough gap for 15mm copper piping to be hidden behind?
Not sure I follow that one , lets have a pic.Also outside i have a new upvc window with 2 concrete lintels above(inner/outer) with damp course spanning above the inner lintel ,down across cavity and under outer lintel. Where the damp course is ie. loose under the outer lintel –
4. How do i render up onto it without the dpc falling off the underside of the outer concrete lintel, and without the fresh render from falling off the surface of the dpc.
Apologies if Q4. sounds confusing , i may have to show a pic