Smells in bathroom

[Pookiewoo]

Hi all,
Parents had a 2nd floor bathroom fitted a couple of years back, and have subsequently started having some pretty vile smells coming through. I imagine it is sewer gases rather than a ''user issue"! My dad said that there was an AAV fitted (possibly under the floor?), which means that it is not easily accessible. As far as I can understand, from research online, either the AAV has failed or is in the wrong place (i.e it would be lower than the wash basin). Can I install an above roof vent to the external stack pipe? Will it cause any issues to have both an above roof vent and an AAV on the same line? (Just in case the problem is elsewhere)...
Cheers in advance

 

[flameport]

Will it cause any issues to have both an above roof vent and an AAV on the same line?

No, but if the AAV is under the floor, it needs to be removed. Highly likely that water and worse is leaking out of it.

 

[Pookiewoo]

Thanks for that - not something I had considered...
I assume that any leakage would've come through the ceiling below. If it isn't leaking now, is it likely to start by me creating an external air vent, and thereby changing the pressures in the existing pipework?
Thanks in advance.

 

[oilboffin]

Aav needs to vent above spill level.Bob

 

[flameport]

If it isn't leaking now, is it likely to start by me creating an external air vent,

No, but being located in the wrong place is an invitation for it to leak anyway.

It's a basic one way valve, designed to let air in but not out. If water gets to it, you only need a small amount of waste to get on the seal for it to never close properly again, after which it will leak both smelly gases and whatever waste happens to pass that way.

 

[Hugh Jaleak]

You wont need an open vent and AAV on the same line, an open vent is far superior to an AAV anyway, and the head of the drain should always be vented anyway. AAV's fitted in the wrong places or instead of the correct open vent can lead to various issues, at best unwanted odours, at worst waste leaking into the room.

In particularly spectacular circumstances, cleaning a sewer with high pressure water jetter can cause a blowback via the WC, redecorating the room.....

 

[dilalio]

You wont need an open vent and AAV on the same line, an open vent is far superior to an AAV anyway, and the head of the drain should always be vented anyway. AAV's fitted in the wrong places or instead of the correct open vent can lead to various issues, at best unwanted odours, at worst waste leaking into the room.

In particularly spectacular circumstances, cleaning a sewer with high pressure water jetter can cause a blowback via the WC, redecorating the room.....

Gotta love a good old $hit-shower

 

[securespark]

Rather you than me....

 

[dilalio]

Well, you're a spark so you don't like getting your handy wandys dirty wirty

 

[HERTS P&D]

In particularly spectacular circumstances, cleaning a sewer with high pressure water jetter can cause a blowback via the WC, redecorating the room.....

I've done that before.

Andy

 

[Hugh Jaleak]

Dont think you're a jetter man unless you have Andy. We went on a training course on 'Blowback avoidance', various hints and tips on how to minimise the risk, but even then he said you cannot remove the risk entirely. Our Managers face was a picture.

 

[durhamplumber]

I've done that before.

Andy

Rofl....one to look forward to.