Smell from downstairs toilet....and no not from us

I_have_spoken

Could be a positive pressure imbalance so that bubbles of foul gas is getting pushed around the U-bend even if there's some water there. Are there any industrial units that could be sending large volumes of water into the drains after 7pm?

Also are you sure it's a pong from the drains and not, say, a dead rat under the floorboards.

Norman_Castle

Smell from downstairs toilet....and no not from us

Sorry dan. You know the rules. Who smelt it, dealt it.

Davesnave

I had a horrible intermittent smell coming from the toilet next to my room when I was a student in halls of residence.

The site caretaker/handyman checked it out and found nothing. The tutor responsible for that hall suggested that it might be my socks, and most of the other students made suggestions I definitely shouldn't write here.

A bit tanked-up one night, and frustrated when the smell returned big-time, I got my toolkit and took up some of the rather nice hardwood flooring. That settled it. There was effluent from a broken or fractured pipe under the room.

Could your problem be similar?

Bykerlass

We had a problem like this as did my son in his new home. It turns out that the durgo valve was the problem in both cases.

A simple job to rectify, once you know the location of the valve. Have a google of Durgo valve for explanation.

firefox1956

A dead rat under the floor boards would smell all the time......
Positive pressure idea might be worth looking into.....
If you can safely leave the outside manhole cover slightly open see if that stops the pong ??
HTH

gallygirl

My friend had this - it was a well rotted smell rather than fresh. Eventually traced to the sink downpipe - it wriggled about too much and was letting air up from the drain below. Plumber found it had just been shoved in a larger hole rather than use a reducing connector. Took months to get to the bottom of it

dantheman2010

I think we have solved it.

It may have been a mixture of two issues. The seal on the pipe going into the floor from the back of the toilet pan wasnt sitting right so we replaced the pipe altogether. Since then no smell from the actual toilet.

But we noticed still getting the smell outside. I noticed an observation/inspection chamber in the back garden and checked this and it was well and truly blocked. The drain from the kitchen sink was struggling to pass this chamber and join on to the utility room drain.

I got this unblocked and I think it has solved the issues.

Going to wait for everything to settle over the next few days and see if we get any more problems.