Nasty Sewage Smell

KimboSelecta

Hi all,
I live in a ground floor flat and have noticed over the last month or so that whenever my upstairs neighbor runs his shower, my flat starts to smell like sewage. Why could this be happening? Any help regarding why and how to fix the problem would be much appreciated.

Thank you

spadoosh

Plethora of reasons.

My immediate assumption would be a failure somewhere in a trap which is allowing the smell of waste back up through your pipework.

KimboSelecta

Is there an easy way to find out what the issue is or would I need to contact a plumber?

spadoosh

I dont know what it is so i dont know, sorry.

My assumption is a trap failure so id smell waste pipes you have, noting which wastes are most likely to share a connection and see if you can locate anything that way. If i couldnt do anything from that, id be calling a plumber and worrying how expensive its going to be.

akira181

are you sure it's just their shower that causes the issue? Has the problem come after renovations (his or yours) or is it just out of the blue?

If your pipework allows for it, run the tap for a bit then shine a torch down your drains (sink, shower, bath, etc) to see if you can see the water level in the trap (the U-Bend). Next time the smell comes around, have a look in the traps to see if the water level has dropped. You may be able to smell which drain it's coming from but it's not always obvious.

If it has or it's definitely coming from a drain, his shower waste water draining away is siphoning your trap(s) and breaking the water seal. The cause could be a number of reasons but if it's out of the blue, it could be a faulty air admittance valve or blocked external vent.

Temporary fix would be to run your taps to refill the trap to recreate the water seal, easy fix would be to install an anti-siphon trap if you have space for it, proper fix would be to find the blocked/broken vent if that's what it is. I installed an anti siphon trap on my bath as getting to the external drain stack vent in my building is a nightmare.

nirajn123

We had a slightly similar issue when we brought our current house - it may or may not be applicable in your case. We used to get bad sewer smell on a windy/wet days and after using the dishwasher. We spent considerable time (with help of a plumber) tracking it down and all the U bends etc were in good order, what we didn't find out until much later on was that previous owner had left an open kitchen waste pipe over storm drain (rather than connecting it) which was hidden below the decking - and the smell would enter the house through air brick which was beside it. It was only when we did some work which required the decking to be pulled up we found it out and properly connected to the waste. See if there is any section of outlet that is hidden which might be leaking at ground floor (especially near an air brick).