New bathroom waste/soil pipe advice

[TonyS82]

Hi everyone

I have just had a small GF extension built as part of a renovation which is being used for a small shower/toilet room. I wanted to get some advice regarding the internal waste before I mess it up.

The new soil pipe enters through the foundation and goes to an inspection chamber where it meets the existing soil pipe from the 1st floor bathroom. It's a combined drain so the surface water will also go into it via a gully/trap/drainage channel.

I am planning to run the shower waste and basin to a low level manifold where the pipe comes through the screed and then connect the toilet pan directly into the top of the manifold via a soil branch or elbow and shallow wc connector. I was intending to use HepVo traps on the shower and basin and will be running it all in either 50 or 40mm pipe. it's a maximum run of 2.5m from the shower to the manifold.

Does anyone foresee any issues doing it this way? Am I likely to need an air admittance valve in there somewhere?

Thanks for your advice

Tony

 

[Hugh Jaleak]

Couple of points I'd consider, for belt and braces, I'd put an AAV on the top of the 110mm stub stack, and I'd use a shallow shower trap rather than a HepVo valve. If you look for a shower trap with removable dip tube, if gives access for cleaning/unblocking from above, so no need for grubbing around on the floor under the tray in the event of issues.

Again an Anti Vac trap may be better on the basin if you intend to common the wastes, will avoid shower trap getting pulled if full basin is discharged.

 

[TonyS82]

thats great thank you