Plumbing

Horrible smell when toilet in loft is flushed

Anonymous user 09/03/2024 - 3.15 PM

We recently had a loft conversion with a bathroom. Occasionally when the toilet is flushed it makes a strange gurgling noise, the water disappears and dirty water comes up. We then get a horrible sewerage smell on the bottom floor of the house at the back where the soil pipe goes underground. We recently got some repair work done on the soil pipe as it had become disjointed, but the problem is still happening. The existing toilet doesn't do this ? Could this be a venting problem? The builders disconnected the old vent when they did the work, but I don't know how to check if they put an alternative in. I can't see anything from the outside.