Gap between shower tray and plastered wall

[Duckytech]

Hi there,

Looking for help in how to fill a gap between my shower tray and the plastered wall. The tray is lying below the finished plastered wall in one section and as a result there is a gap in one section.

My plumber fitted classi seal to tray and put tray into position. Athough the classi seal is flat against most of wall there is this one area where the seal is below the finished plaster.

I intend to waterproof/ tank both shower area and bath area.

Is there anything I can use to build out this area under the plaster, behind the classi seal, in order to have a flat surface for the classi seal to sit against? I think it's too thick (approx 10mm) for plaster skim and not sure about bonding it out. Maybe flexible tile adhesive?

I have attached a photo to help explain.

Also, as a side note, do I overlap the tanking tape onto the classi seal in order to adhere the classi seal to the wall? Then apply membrane coats x2? Or would I just use the membrane and seal over the classi seal?

Thanks for any assistance.

Cheers,

Duckytech

 

[White Room]

Get yourself some rapid tile adhesive, it may take a couple of layers as putting on 10mm thickness in one go may cause it to flow down the wall.