Wet room

[diyjoe]

I am installing a wet room and have become confused by the showertray manufacturers statement that 1,2 or 3 waste traps of 40mm can be fitted under the linear or oblong grid cover. each trap drains 26 litres of water per min. giving a flow of 26, 52, or 78 litres per min.
Here is were the confusion comes in should I decide to use 3 traps with a possible flow of 78 litres should each trap be fed via a 40 mm waste pipe connected individually to the 110mm stack or would one connection be Ok with all 3 traps being T'd into a single 40mm pipe. I suppose the answer is in the flow rate of 40mm tubing which I can't find information on and the manufacturer seems baffled by the question
Any comments would be appreciated.

 

[Infiltraitor]

If the system flowrate necessitates two or more then they'll all need running back to the 110mm waste pipe, otherwise you're just moving the flow restriction slightly further downstream (and under your floor presumably).

If they're only being used to aid drainage across the wetroom floor and the flowrate isn't a problem, then there shouldn't be a problem in teeing them into a single run of 40mm.

I'd probably still run them individually though

 

[diyjoe]

Space is a bit tight under the floor boards to run 3 pipes and obtain the necessary fall. Is 50 or 60 mm pipe available with approprate clamp or stick on boss

 

[sydneyplumber]

Yeah, 50mm is available. Just ask your plumber and he'll fix it for you!