Is a vertical section of soil pipe allowed between sloping sections?

[Ben_F]

I'm looking into ways to put en-suite bathrooms into two bedrooms which are room-in-roof (2nd floor). The floor level is above the eaves and the soil stack is on the outside wall mid-way between the two bedrooms.

My idea is to have two 4 inch toilet wastes joining into a vertical pipe which will be midway between the two en-suites and going down inside a new partition wall (extra wide partition wall to accommodate the pipe comfortably) on the first floor. Near the bottom of that wall, the pipe will have a bend and then 2 junctions taking waste from two more toilets on the first floor, then out though the wall to the existing soil stack.

Currently, the only feed into the soil stack is at ground floor level. The stack is cast iron and it's a listed property.

The wall is 800mm thick.

The question is, does building regs allow a vertical section of soil pipe inside the building, before it goes though the outside wall?

 

[dontknowitall]

I'm going to wriggle with this one ...

My guess is that's fine BUT ...

I'd check with your authority first. In addition, if you're installing new WCs in new rooms, you'll need a building inspection so if this is the case then you could ask the building inspector and see what he says.

 

[PlumbBobBob]

i agree you need permission to fit toilets in new positions where none were before so just ask advice when they inspect.

 

[Ben_F]

Thanks folks. I haven't put an offer on the property yet, so it's early days!

It looks like I'll need to have a chat with building control at the local authority.

 

[justlead1]

As Dontknowitall says, but some BI"s don't have much experience in this. When checking it out with colleagues they come up with all sorts of problems. Using 92.5 degree tight bends at base/change of direction can be an issue. Venting at this point may be required, Access on bends for rodding. etc. Its no unknown as it has been used where there is a risk of damage to soil pipe ground level by passing traffic. Good Luck

 

[stevetheplumber]

most loft exstensions break all the rules regarding one pipe systems so the chabces are youll be able to do what you want youll possibbly need a durgo or soil to atmosphere