Can a terraced house share a waste stack with adjoining properties?

[linkandnavi]

Morning everyone,

 

We have a bit of smell downstairs in our house and one of the possibilities we're examining is whether there is an issue with the waste removal. There are no obvious blockages (toilet flushing fine, sinks running ok). However, one of the questions that's arisen is the location of our waste stack.

 

Our house is a terraced house, built approximately 1930, and is one of the centre properties in a row of four. Both of the end properties have visible waste stacks coming through the roof. Both my property and the other "middle" property do not. Nor can I find anywhere in the property where a waste stack could reasonably be hidden or make it's way up through the house to to the attic. We have no upstairs water (the bathroom is on the ground floor and I believe this is the same for the other houses on the row, so I assume this was the standard model for our road when built).

 

I'm wondering therefore if our house shares a waste stack with the adjoining end-terrace property (and the other "middle" neighbour with their adjoining end-terrace property). Is that possible? I've attached a crude Paint drawing of the layout. I've looked at other terraces on our road. Some have waste stacks coming up from every property in the row. Others seem to only have them on the end houses, although the middle ones could have them out the back and just not visible from the road.

 

I've looked in the attic for a Durgo valve and can't immediately see one although access and visibility is limited due to boarding etc so it's possible that it is just hidden somewhere. Although, as I say I can't see any obvious route up from ground floor to the attic that a pipe could take.

 

Finally, I don't think that an existing waste stack has been removed at any point. (a) There is no obvious alteration to the roof where a previous pipe would have been and (b) I've managed to locate the drawing plans for the extension (wet room) that the previous owners added to the property. That includes a note on the wet room plan that says "New stub stack to connect to existing foul drainage system once found and exposed on site", which suggests that they didn't know where the existing one was either. I'm fairly sure they didn't add the stub stack to the wetroom when they actually built it as there is nowhere obvious that it could be concealed and the wetroom bears no relation to the drawing plans anyway, but that's an issue for another day.

 

Any advice gratefully received.

 

Thanks,

 

Matt.

[Temp]

As I recall it is allowed to share an open vented stack between several houses (5?).  However most BCO prefer each house to have one, usually at the furthest point from the main sewer in the road. 

 

Their main purpose is to ventilate gasses from the sewer system but they can also help prevent water being sucked out of traps by fast flows like flushing loos or showers. If that happens smells can get back in.

 

I would try and locate which trap is causing the problem. If it turns out to be a basin it might be easy to add a small AAV under it.