levlling low profile shower tray - TilersForums.com

[si123456]

Hi any help would be appreciated,

1)Joists are not level
2)replaced floorboards with 18mm ply
3)6mm tile backer board then used (Marmox insulation)

Can I put the marmox tile backer under the shower tray and then use self leveller to level the base of the shower tray? Or will the cement backer board and self levveller not be strong enough?

Any other ideas to level the low profile tray not using an easy plumb kit would be great!

Thanks

Simon