Falls on a shower base

manufan16

I am in the middle of a self build and I was hoping for some advice regarding shower bases and how best to calculate and make the slope?
I used a self levelling screed throughout the house so I boxed off the shower areas.

Somebody suggested filling the base 60% sand and cement mix and then the tiler makes the slope with the adhesive while tiling , is this the usual method or are there any other ways?

apache6

Most, if not all shower trays are fitted plumb level on the floor, the fall is built into the structure of the shower tray itself.
In other words put your shower tray level on the floor pour water into it and the water will be directed to the plug hole by the inbuilt slopes within the tray itself, they are built with the fall to the outlet factored in.
Hope i've explained that alright.
If you are not using a tray and are just putting tiles straight onto the floor, don't do it unless a)it's a downstairs shower b) if it's upstairs that you have concrete floors, ordinary houses with wooden beam/rafter floor/ceilings will always move and flex so tiling onto the floor is asking for trouble.
I am an expert on showers and leaks, i'm sad to say.

manufan16

Thanks for your reply but I'm not using shower trays, the base of each shower will be mosaic tiles into a shower gully.
I want to ensure that the fall is right.

apache6

are you putting it on a concrete floor, if so your tiler will run his floor tiles (mosaic) at a gradient towards the waste trap using a levelling compound to create the slope.
Talk to your tiler, i would very strongly suggest he 'tanks' the lower part of the shower walls and the floor.

manufan16

I don't think I read all your message or else you added to it while I replied!

Iv 1 downstairs , 2 upstairs and I have concrete floors in.

The bathroom floors screed is 55mm thick but i have no screed in the shower areas as it was self levelling to no good for getting the fall so Im wondering how to build this area up

manufan16

Ok thanks - its levelling compound that is used :-) I have tanking kits too for the shower and bath areas.

Is there a rule of thumb for slope ? As in every 1000mm it drops 10mm or something like that?

apache6

OK Concrete floors that a different matter, they will be fine as there is no flexing etc. Not my area i'm afraid, talk to you tiler - he will advise whats best.

apache6

have a look at this, i know it's Canada but the principles are the same.

http://www.ontariotile.com/preslope.html