I have a 1100mm x 900m resin shower tray to slot into a cob and stone alcove with a solid floor, with no space for stud work.
The alcove has been panelled with 18mm marine ply and the floor raised with 4 pieces of 100mm x 75mm timber with 18mm ply on top, the tray will sit on 6-10mm of floor tile cement adhesive. A gap of 6-8mm has been left around the three sides between the tray and the ply.
Then to Aquapanel (12.5mm) the walls down to 6-8mm above the tray then tile down to 4mm above the tray. Knauf have advised not to seal or tank the ply or Aquapanel.
The planned sealer adhesive is Everbuild PLUMBERS GOLD between the walls of the tray and the ply and the bottom of the Aquapanel.

So questions

Do I prime the ply with say waterproof Unibond or Bonda Wood Hardener diluted with acetone, just where the PLUMBERS GOLD needs to stick.

Will PLUMBERS GOLD fill a gap that big (8mm) or would a gap filler be better say Pink Stuff

Will the standard Aquapanel 40mm screws hold Aquapanel into 18mm ply or to use adhesive as well or a shorter screw.

Screw the Aquapanel screws in with gentle care or the usual Makita Impact driver

Will PLUMBERS GOLD hold the tray in place.

Any advice and ideas greatly appreciated.

Regards David

Ok, firstly if your fixing the aquapanel to the ply, how is the ply fixed?

As long as the ply fixings can take the weight of the aquapanel then you should be fine.

i would recomend you tank as well as aquapanel is not waterproof in the sense it wont let water through

to the forum

Thanks for coming back to me, the ply is fixed to standard spacing 100mm x 75mm stud work with pink stuff and a 6mm x 70mm screws 150mm apart. You say firstly, any other ideas? Regards David

Hi If I tank the ply and the tiles leak so the Aquapanel gets wet, then I repair the leak, won't that mean that the Aquapanel will never dry out. Where as if the marine ply is not sealed and gets wet from one side it will dry out to the other side and the Aquapanel will dry as well?