Decoupling membrane over proforma/wetroom shower tray?

[jkanji72]

Hi All,

Can someone please advice on the following.....

I have a proforma shower tray (20mm) that is sitting on the joist . Butted up against the tray is 18mm ply to form the wetroom floor. Question - do I lay decoupling membrane over the shower tray and ply? or can I lay the membrane over the ply only and thus make up the 2mm need to bring ply and tray level?

Thanks in advance

R

Jay