Moving internal soil vent pipe to outside wall

[onionsa]

Hi all, we’re in the process of buying our first home and I’m trying to get my head around a few of the home improvements that we want to do... so this will likely be the first of many posts!

So for this post I’m looking at the bathrooms and toilets. We have a downstairs toilet with the family bathroom directly above it. The soil vent pipe runs up the outer most corner of the house and is boxed in from top to bottom. I’d like to know if this can be moved to the outside of the wall in both rooms, but at the least the upstairs bathroom.

Thanks in advance,
Anthony

 

[Newboy]

1) Does it exit through the roof or is it terminated inside the roofspace?

2) Is there an inspection chamber close to the external wall where the internal stack is?

 

[Hugh Jaleak]

Building Regs advise against bends in the wet section of a stack, so it would need to be moved in its entirety.

Firstly, you'll need to ascertain where the drain runs, if it goes straight out through the wall below ground level, then easy enough to couple on outside the footprint of the house. If it goes off under the house, before exiting elsewhere, it's suddenly a lot more difficult.

Why do you want to move it?

 

[Ian H]

I would definitely move it.

A guy I work with had a bad day on Friday trying to unblock an internal stack, it ended up there was a burried manhole just outside

I got sent over to him to give some emotional support.

 

[onionsa]

Thanks for the responses. The pipe vents through a tiled roof, and by inspection chamber I’m assuming that’s the man hole cover in my front garden. If so, this sits about 3ft away from the front wall of the house. The vent pipe is running down this corner internally. The main reason we want to move it is to recover part of the bathroom so we can put a longer bath in. We may be able to just shrink the boxing but as it had been suggested to just run it outside I though I’d ask. I’ll have to look closer at this ‘wet section’ to understand that.

 

[Nige F]

Front wall of house - it would look awful outside - and you'd have to get building control in because drainage is notifiable. But you might be able to take the pipe just above the upstairs WC and go through side wall and up - pictures/drawings would be useful

 

[onionsa]

Yeah I agree about the front - I'd be looking to run it up the side of the house if possible as this would be hidden, the corner bricks of the house extend past the wall face. I'll post some pictures up later on - anything in particular that would be helpful?

 

[Hugh Jaleak]

I'd have a good measure up in the bathroom first. Its easily possible to reduce the dry (vent) section of the stack to 82mm (3") pipe from above the WC branch, which may provide that little bit of extra room you need.

 

[onionsa]

I'll get back under the bath tub tonight with the tape measure and see what's what. If I was to reduce the diameter could it also be angled back towards the wall to eek out that bit more space and then angled back out in the loft space to keep the same vent exit from the roof?

 

[Nige F]

Pictures of the side of the house and the under bath area and general bathroom

 

[onionsa]

Managed to get under the bath but it was dark when I got home from work.

There is 150mm between the current end of the bath and the soil vent pipe. And as you can see there is a pretty big boxed section in the corner of the room which we'd like to get back if possible.

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Thanks again for all your inputs so far.

 

[Hugh Jaleak]

I'll get back under the bath tub tonight with the tape measure and see what's what. If I was to reduce the diameter could it also be angled back towards the wall to eek out that bit more space and then angled back out in the loft space to keep the same vent exit from the roof?

Yes. Put as many bends as you like in the dry section.

 

[onionsa]

Cool, so what I’m thinking then is if that white pipe from the sink is run lower down nearer the floor I can then get a bend above it to move the vent pipe right up to that wall corner and have a much smaller boxed in section.

 

[Nige F]

Crack on with that

 

[onionsa]

Great! Thanks for confirming