Max length of drain pipe for bath/shower

[JJWJB90]

Hi everyone,

I'm an interior designer working on a small residential project, and have a bath that is approx 5m from a vented soil stack, with one bend in the pipe as it exits the building to the exterior then connecting to the stack. I know building regs stipulates that the max run of a 50mm soil pipe is 4m, but read elsewhere that I would be able to achieve longer runs if I add an air admittance valve somewhere along this soil pipe. Does anyone have knowledge or experience of this?

Thanks

 

[Deleted member 120897]

I would say it’s ok to fit an air admittance valve, see 1.20:

 

[Ben-gee]

It will be fine.

However if the work you are doing requires signing off by building control just ask them how they wish you to do it- you don’t want to have to change things later.

 

[JJWJB90]

I would say it’s ok to fit an air admittance valve, see 1.20:

Thanks so much...I don't how I managed to completely miss that point!

 

[JJWJB90]

It will be fine.

However if the work you are doing requires signing off by building control just ask them how they wish you to do it- you don’t want to have to change things later.

Ok thank you good advice

 

[Timmy D]

Just don’t do it like this one I saw yesterday.

And the tee where the vertical meets the horizontal on the side wall has been installed backwards.

 

[Deleted member 120897]

Just don’t do it like this one I saw yesterday.

View attachment 63771

And the tee where the vertical meets the horizontal on the side wall has been installed backwards.

Was it supposed to be on where X marks the spot?

 

[JJWJB90]

Just don’t do it like this one I saw yesterday.

View attachment 63771

And the tee where the vertical meets the horizontal on the side wall has been installed backwards.

Thank you...what a mess!

 

[Ric2013]

Thanks so much...I don't how I managed to completely miss that point!

I don't remember that being in part H. It used to say ventilation without suggesting an AAV and I must have studied an outdated version while at college. Seems part H has finally caught up with technology and thanks so much for bringing this to my attention. It always made sense that an AAV would solve the problem, but I always thought it wasn't a solution suggested in Part H.