Correct way to fit low profile shower tray?

I purchased the following Duravit Shower Tray (1500x700):

https://www.duravit.co.uk/products/all_series/starck_tubs__showers.com-en.html?product=1616323

I have not yet unboxed it, but from the drawings it looks like the profile on the bottom of the tray is sloped - with a 20mm 'lip' all the way round.



My bathroom floor is 22mm board on top of timber joists.

What I am unsure of is how to fit this properly so that all the levels are correct. The rest of the floor will be tiled with 9mm thick tiles.

The manufacturer's instructions only give instructions based on mounting it on the the manufacturer's mounting kit - which raises the level of it - but not sure that will help me for mounting on the floor.

Any tips would be appreciated.

 

Hmm, that's not great for going onto a wooden subfloor given it isn't flat underneath. Looking at the MI, it uses wall clips and riser legs normally so it sits up and it is supported around the 20mm lip, which isn't a lot tbh.
Probably need to create a frame the same width as the lip and sink that into the floor but that would need to be at least 55mm down into the joists to accommodate the run, to much for the joists unless you really strengthened them.
It would really need to sit across on top of the joists, so it would be at least 32mm above the floor level but again supporting a tray like that on a 20mm rim, isn't a lot.

You really want a tray thats square and flat underneath and has the run built into the depth of the tray TBH.

 

theres plenty on the market at 20mm deep with a flat base.
cant stand ‘riser kits’ or tray fitting kits of any description

 

Thanks guys. I think this unit will be more trouble that it's worth so I am going to just return it. Serves me right for just assuming that it was a flat base unit and ordering without checking the mounting instructions first!

Now to see if I can find a more suitable 700mm x 1500mm shower tray!