Adding branch to existing stack

[ParisPark]

Hi,

I am looking for a bit of advice before I call a pro in.
I need to insert a tee branch into our existing soil stack, for a downstairs loo.

My problem is there doesn't appear to be enough clearance above ground level for a coupler to slip on top of the pipe that protrudes from the concrete.
There is an access hole on the rear of the pipe, meaning I will have to cut it below this, leaving around an inch of pipe left sticking out of the ground.

Would this amount of pipe be adequate for something like this to slip over and be secure?
https://www.toolstation.com/shop/Ro.../Soil+&+Vent/sd2849/Flexible+Equal+Tee/p50188

Or is there some other way to do this I haven't thought of?

 

[Doggit]

Work out the fitting you need for the branch etc, and then cut the pipe so that you can solvent glue this fitting in. Then you can drop the new branch ito it, and then rejig the white waste pipe to reroute into a boss in the branch.

After that, if there isn't enough spare pipe left in the vent section, you can fit a small piece above the branch, and then join them with a slip coupling

 

[ParisPark]

Thanks for the reply.
Would the attached fitting slide inside a standard 110mm pipe, i.e. act as the male end?

I can see there is a female join right at the concrete level, but I'm concerned this will not come apart cleanly so I'll need to have a backup in place before I break the pipe.

 

[Doggit]

Cut the white sink waste, and then see how many joints come apart. I can see the joint you've mentioned, and if you're lucky, that one'll come apart, and you then rebuild from there. If it doesn't, then you've got to cut it below the rear access plate, glue a new push fit socket connector, and then start rebuilding the stack.

 

[ParisPark]

Thanks again. At least then I have a backup plan if they don't come apart. Would this be used to slide in to the existing pipe if I need to cut below the access plate?

 

[Doggit]

That's it. You need to solvent weld that in, so make sure you get a tin of that as well, but you often have to ask for it, as it's a sniffers paradise. It doesn't need to go right down into the lower part of the stack, and if you set everything up before you glue it in place, then you can find the right height to set it in place.

 

[ParisPark]

Perfect. Thanks a lot. I'm quite confident I can attack this job now.

 

[Hot&Cold]

I am looking for a bit of advice before I call a pro in.

Perfect. Thanks a lot. I'm quite confident I can attack this job now.

is your Pro on holiday ?

 

[ParisPark]

I don't have a pro, but would call one in if I didn't feel up to the job.

 

[Hot&Cold]

I don't have a pro, but would call one in if I didn't feel up to the job.

great stuff.
depending on your location some building control involvement could be required

 

[ParisPark]

Thanks for the heads up. I'll give them a call. They are still due to come sign it all off anyway so can get them to check at the same time.

 

[John D v2.0]

I think your biggest issue if you get building control involved would be proving that the branch is far enough above the invert below the stack! There's not much else on such a small modification.
Personally I wouldn't bother, but it might be worth reading the approved document for drainage first.
If you're planning to sell the house it might cause questions though. Good luck!

 

[ParisPark]

I think your biggest issue if you get building control involved would be proving that the branch is far enough above the invert below the stack! There's not much else on such a small modification.
Personally I wouldn't bother, but it might be worth reading the approved document for drainage first.
If you're planning to sell the house it might cause questions though. Good luck!

Interesting! Thanks, I will see how deep the pipe goes when I get it open, hopefully it is about the minimum distance.

 

[Hot&Cold]

If you're planning to sell the house it might cause questions though.

It sure does,depending your uk location a vendor has to list alterations on the TA6 form,some tell fibs thou.

remember household diy work has its legal limits but some people say an alteration is a repair with modern materials (nude nude say no more).

Happy plumbing

 

[Ian H]

Thanks again. At least then I have a backup plan if they don't come apart. Would this be used to slide in to the existing pipe if I need to cut below the access plate?
View attachment 134614

That won't slide onto the pipe, that would fit over it. There are internal drain connectors that will go into the pipe, ones an S464 but there are a few others too.

I think best to get rid of the white pipe and see if the fitting will rotate in the joint below the floor. If it does it will pull out and be a nice easy job.