by plumbbob »
Fri Nov 28, 2008 9:09 pm
Think you may be getting a little confused here. Some shower trays are supplied with optional legs. The instructions show installation for both systems.
If the tray is to sit on a concrete floor or 18mm marine ply, it is recommended that the tray sits on a bed of mortar which will even out any undulations in the underside of the tray. I have installed, and removed hundreds(?) of trays over the years, and I can count on one hand how many have used mortar. It all depends on how flat the underside of the tray is. Normally, I use silicone to fix the tray to the ply. It gives a good fix but not a permanent one.
If you are going to use legs, then marine ply and mortar are not required. Fix the legs to the tray and fit in position. One point worth mentioning is be aware how strong the t&g flooring is. Often the legs are over holes in the boards, or on weak spots allowing the tray to move when stood on. A definite no no!
Before now, I have fitted ply to the floor to strengthen it then stood the tray legs on that.
If you can, chuck the legs away. They are c**p. Put three or four lengths of 3" x 2" or 4" x 2* and fix 18mm ply over (some instructions suggest using green flooring chipboard which is much cheaper than marine ply), check that the tray bottom is flat and if so, fix as I said. Just make sure the 4x2 is level before fitting the ply which in turn must be flat and level.