Drainage smells in the house

[Norm29]

Hi, we have drainage smells downstairs, inside the house but they don’t seem to be coming from a sink etc. No local company offers smoke testing so I’ll likely be making some sort of contraption to test it in the future. My question relates to other improvements or fixes that might be needed.

The soil stack exits from a roof below the converted attic and en-suite. There’s no opening/aav above the previous.

1. Should there be an aav on the highest point?
2. Can I fit an aav on the soil stack to avoid smells when roof windows are open? I know it’s generally not recommended but any experience?

Thanks

 

[Wayners]

Some ideas
Washing machine.
Liquid tabs cause sludge and stink like rotting eggs so check that.
Run cleaning cycle. Follow instructions as not obvious how to do it as you may need to hold buttons down to trigger.
We also have a shallow drain pipe running out our back, so I pushed some wire along, then tied a rubble sack to wire end and pulled through.
It's didn't half stink pulling the crud out, although fine now it's cleaned soil pipe as it seemed to be smelling around our kitchen sink area, but not the sink itself.
Fixed though, although I still don't know how drain smell was getting in?

 

[foxhole]

Where are smells stronger ? Have you kept doors closed to locate likely location?

 

[HERTS P&D]

Blocked manhole or dead rat under the floor.

Andy

 

[Norm29]

The washing machine is in a conservatory, outside, next to the downstairs toilet. Doesn’t smell in there. Smells near the horizontal I’ve drawn, I think there’s a gap on the top somewhere as no leaks

 

[blup]

If you get siphonage when emptying the basin or bath, an AAV might help. But first rule out blocked manhole, and, using the smoke test, any physical cause.

 

[Hugh Jaleak]

Stack needs to be open at some point, should really have been extended upwards to clear the Attic Window openings when they were fitted. Fitting an AAV may only make the issues worse to be honest. What's on the top of the en suite stack?

 

[Norm29]

If the existing stack were to be extended, it’d be several metres up. The attic/roof lights are on a gable roof with the stack coming up through a single pitched roof, lower down.

No opening on top of the en-suite stack, it extends up to the attic bathroom with just the wc, shower and sink. That was where I thought about adding onto the stack and create a new vent outlet with Aav as there’s some crawl space next to it I could use.

 

[Hugh Jaleak]

If you're going to add onto the en suite stack, then that needs taking through the roof as an open vent, allowing you to cap the existing with an AAV.

The drainage system needs to breathe, capping open vents with AAV's doesn't allow positive pressure to escape, so it looks for another way out, usually through a shower trap.

 

[Norm29]

Appreciate the advice! Seems like neither of my original proposals add any value

 

[HERTS P&D]

Are you sure there is not a wiring fault somewhere?

Andy

 

[Norm29]

Are you sure there is not a wiring fault somewhere?

Andy

Why would wiring have any impact?