We’ve constantly got a funky/foul smell in our spare bath room. It’s a kind of mouldy/not right smell rather than smelling purely of sh%$te. I’ve ruled out any leaking pipes/mould issues anywhere as we recently replaced the sanitary ware/shower etc and the smell was there both before and after!

The two top windows you see in the photo are our two bathrooms. The large pipe is the soil pipe that takes the waste from the two toilets. It goes down through our conservatory and down into the main drain. The bathroom on the right is the one with the funk. The smaller pipes take the used water form the bath/sinks/shower etc.

I’m thinking it might be an issue with the foul smell coming up the pipes and reaching the highest point which might be our spare bathroom. I guess my question would be shouldn’t the ubends stop any smell entering the room?

Any ideas what might be causing it?

Check your air admittance valves, should be at the highest point, so probably sink traps… If these stick closed the water in your traps is pulled through leaving you with a smell!

^^^ that and fit anti vac traps

The u-bends need to have water in to stop the smell, don’t forget.

I say this, because I had similar in mine, and it took me a couple of days to realise that I just don’t use the bath from one month to the next*. Ran the bath tap for 30 seconds and, hey presto!

*I do shower, just not bath, to avoid derailing the thread!

Run some water and see if the smell goes away – drains get smelly if they dry out a bit which could be the case with a spare room.

Check your floor boards around the pan, do you have carpet or vinyl. Could be a tiny leak around the joint behind the bend.

Looking at how that has been piped there’s a possibility when one piece of sanitary ware is being used it is inducing a syphon affect on something else. when you have a shower or bath and the water goes down the drain. Do you get any of the basins or what ever your not using make a gurgling sound?

when you have a shower or bath and the water goes down the drain. Do you get any of the basins or what ever your not using make a gurgling sound?

yes. often when i turn off the shower the basin plug gurgles.

what does this mean exactly and if it’s causing the pong whats the fix??

Sounds like water is being sucked out of the basin trap due to incorrectly piped waste pipes. this makes it so the trap isnt doing its job and the pong will possibly be entering at the basin. when it pongs smell the basin plug hole 😉 To help cure it youll probably need to fit some anti vac traps