New stack pipe

[grommett]

Hi

I am intending to install a new stack pipe for an additional 1st floor toilet. The new stack will be approx. 1 to 2 meters upstream from the end of the existing system (and around a corner) which is also where the existing stack is. My question is does my additional stack need to be vented if the existing one is already?

Many thnks.

 

[seco services]

building control should of told you.

 

[waterworks]

If you mean you are going to renew underground drain and new soil stack then yes you will need to vent above highest window approx 1 metre.

The vent pipe is required to stop the flush from the toilet causing self syphonage which will remove water seal in wc pan and let in foul smells from sewer.

 

[grommett]

My intention is to leave the existing vented stack in place and extend the underground drain for a meter or two and then add an additional stack for the new toilet. Hope this makes sense.

 

[waterworks]

Then yes you will require a vent.

 

[grommett]

Thanks for the advice - very helpful. Before I start, I have a Plan B. This is to branch off the existing stack pipe. It is less than 2 meters from my new toilet but it will mean using 3 elbows between toilet and branch in order to get around the corner. Is this OK?

 

[larrytheleak]

grommett you should go for plan b no problem with bends use a 92& 1/2
degree single branch at existing stack then bend round corner & bend trough wall to loo a branch less than 3 meters long will not need venting
hope this helps