Bathroom stinking after installing Durgo

[9namjam9]

So I noticed the main soil stack in the house I just bought terminated in the attic and was open for 6 years since the house was built , so its caused mould on the timbers around it. 

I put a Durgo air admittance valve on so it wouldn't pollute the attic, and the toilets would flush OK, but since then the bathroom drains have been stinking up the place, the bath p bend in particular i think. Its not dried out. I'm guessing this is positive pressure from the soil stack maybe? Do I need to get the soil stack extended out of the roof, or is there anything else I can try?

[Dave Jones]

if the soil stack is already in the attic can you not simply run it to a tile vent ?

[9namjam9]

4 hours ago, Dave Jones said:

if the soil stack is already in the attic can you not simply run it to a tile vent ?

I wouldn't find that simple but yes that's what i thought might fix it. Just wondered if there is an easier way

[tonyshouse]

Sounds all wrong to me, are the drains partially blocked or bits missing from the traps? 

[ProDave]

10 minutes ago, tonyshouse said:

Sounds all wrong to me, are the drains partially blocked or bits missing from the traps? 

Might be worth getting a plumber to pressure test the drains to find problems like that.  I wonder how many houses actually get a proper drain pressure test?

[saveasteading]

My guess is that the stink used to vent in the attic, but the valve now prevents that. 

Now when there is any pressure in the drains it forces bad air through any weakness. 

I would check the wc drain seals. the tiniest hole can allow smells through.

I once found a tiny gap in the plumbers' mait seal, but only by getting into very uncomfortable positions. Problem solved.

[9namjam9]

I was just quoted £700 to run the soil pipe out of the roof. No scaffolding is needed. It seems like alot to me?

[saveasteading]

Removing durgo and extending through the roof?

 

Sounds ok to me for a proper job, if so it proves.

Materials £50? pipes, joints, flashings.

Cutting though roof.

Making watertight again.

Somehow getting access on the roof safely and securely enough to do a proper seal????

 

2 workers all day x £200 or whatever around your way.

Add risk and sundries.

 

Option might be to vent from the external drain, further along the line. Stink around wherever it vented.

 

But you shouldn't need it if there is no hole in the drains for the smell to come from.