the mystery smell

[stevewilliams]

Hi Experts

This is something I've been trying to figure out for a while now and hoping there's an obvious thing I've missed before I have to start ripping into the fabric of the house.

When the wind is blowing from a northerly direction (and only then) we get a sewage/drain smell in our utility room. The stink pipe runs through this room - boxed in and hidden - and up through the bathroom directly above which also gets the smell when the wind is strong (yeah I know there's a joke in there as well ). Where it emerges through the roof I can see it is sheltered from the wind in all directions except north by the roof valley. It doesn't stick out more than 30cm or so from the tiles.

My only theory is that wind is blowing the smell back down into the house or maybe even sucking the smell from the sewage side and somehow it is leaking through a joint in the stink pipe not correctly sealed? I can't see any other way as there are traps on all the loos, sinks etc.

Your thoughts and theories greatly appreciated.

Steve

 

[Tay7]

As an indicator, does the water move in the toilet on these windy days?

The differential in air pressure over the roof might be sucking the traps somewhere down the line.

 

[stevewilliams]

No these seem OK and wouldn't the traps have to completely emptied to let smell through?

I did just run water into the utility room sink to make sure the trap was full but the smell persists as long as it's windy outside.

 

[Tay7]

Dunno then. Is it coming from a particular sink for example?

 

[Doggit]

Pictures inside the utility room, and outside the house please

 

[stevewilliams]

The utility room only has a sink and washing machine that share a trap and feed into a pipe which runs behind a stud wall and then into the soil pipe so nothing there to see really - I'll take a picture of the roof and send it next. The smell is kind of all pervasive and hard to pin down so wondering if it's some kind of connection hidden behind the boxed in soil pipe? Presumably this soil pipe is one continuous length with collars and connections for waste pipes - could these be fitted incorrectly so that smells could escape but not liquid?

 

[stevewilliams]

The small pipe just above the gutter is the vent for the soil pipe.

 

[HERTS P&D]

Take a picture of the set up where the washing waste goes and where the waste goes into the wall. Sometimes you can get siphoning back to the washing machine causing smells. You also may a blockage in the manhole.

You can also try a maintenance wash on the machine, it is when you set the machine to the highest temperature and run it full cycle with no clothes or detergent in.


Andy

 

[Doggit]

It's possible that the problem lies behind the boxing, so you'd need to find and (temporarily) seal all the holes as a test. A handful of soda is normally recommended for the maintenance wash.