Why are shower trays 760mm wide, I know you can get various sizes and shapes but my 'logic' says that a tray between the 700mm wide and the 800mm wide should be 750 not 760. Why has this size been selected? I am fitting a tray for a neighbour and their old tray (acrylic) was 750mm wide and it fits into a three sided alcove. The tray they have bought is a 760mm but actually measures 768mm!! I can chop out the wall on one side but the other side is one of those 'straw' walls I mentioned a few weeks ago on a different subject. The new tray (stone resin) has built in upstands so they need to be set in to allow the overlapping tiles to lay vertical so the door frame sits vertical aswell. The old tray was higher than the new one so there is some exposed straw, where the house builders did some chopping out when fitting the original tray. When I have chopped out some straw can anybody advise as to what I can cover the straw with to allow the tiles to stick? The original covering is a paper layer and a plaster skim, would plaster stick to the straw successfully or do I need to do something else first?
Cheers
John