Sewage smell in downstairs toilet. Shared stack with toilet above.

[crappy]

Hi folks,

I have a crazy smell in the downstairs toilet which has built over the space of a week or so.

In our downstairs toilet we have the main stack which runs under the house into the main sewer and also up to the upstairs toilet and bathroom.
This downstairs toilet shares a wall with the utility room which has washer and basin in it.
The main stack is boxed in which I've now removed to check.

I cannot see any cracks or weeping at the joints, nothing wet as it goes into the concrete floor.
The top of the stack, and boxing, which runs vertically up, is blind and has an "aeration valve" on it. This valve is likely 25 years old. Within this section of the boxing, there is no smell.

Could the valve age and eventually fail open / shut?

I've got a plumber coming out next week for a look-see, in the meantime I'm making access and just genuinely curious as to what this could be

 

[Wayners]

McAlpine Air admittance valves are good.
Swap yourself as they can fail. Changed mother in laws last year which was about 18 years old

 

[HERTS P&D]

Check your manhole.

(Where are you in Herts)

Andy

 

[crappy]

McAlpine Air admittance valves are good.
Swap yourself as they can fail. Changed mother in laws last year which was about 18 years old

Thanks. I cannot smell anything around the valve but it's upstairs, in the box void. Perhaps the smell just sinks. I'll give it a go. They standard 110mm? (thick grey sewage pipe)

Check your manhole.

(Where are you in Herts)

Andy

Manholes all clear. I'm well versed in those from other septic tank issues... . The things I've seen from my neighbours... Must have brought a tear to her eyes.