Richie

UPDATE: Builder was up and removed the 2 toilets with the plumber, he did say the original fittings were not great. Smell is no longer in bathrooms but still in the hotpress( where SVP is located) at random times throughout the day but it comes and goes. He removed the bottom of the plaster board the other day to expose the pipe but on that particular day there was no smell in hotpress. I came home today and went to hotpress and could smell the strong odour. Got on my hands and knees to smell bottom of pipe but couldn’t smell anything from the pipe itself however to the right of the SVP is the underfloor heating pipes and I could definitely smell the odour coming from the back of them. I believe the SVP goes under the floor I hotpress and into the bathroom beside it. I mentioned this to builder but he can’t understand how the smell would come through so much concrete, insulation, radon barrier and floor screed . At this stage I believe a camera maybe be required. I have attached picture of area

From the septic tank to house is approx 15/ 20 metres Kelvin but not sure the exact type. The builder and plumber have just left there and changed the seals on both toilets. ( he did say one wasn’t that tight a fit that was replaced ) Still doesn’t explain the smell in the hot press when the SVP is. Yes Saveasteading extending those 2 pipes beyond roof is next on list of the toilet seals don’t help. Prodave ….we have an upstairs with a small bathroom that the hotpress SVP extends to but there is zero smell upstairs or when i open the inspection hatch to the eaves of the house beside the bathroom i can see that same SVP but again zero smell.

Hi Dpmiller, see attached pic of top soil stack, the vents are flush with roof tiles if you can zoom in. The builder says he always fits them this way and has no issue. However he has mentioned he might change them to 2 pipes extended so they are beyond the roof in case the wind is pushing the gas back down.

Yes, I did remove one of the inspection chambers nearer the house to allow the gas to release and the smell definitely wasn’t as bad but when I put it bad on the smell returned to the usual stench. It’s also seems to move from one bathroom to the other randomly, then occasionally the hot press where the soil stack is located. Is there any possibility the issue could be in the ground below floor screed ?

Yes, there are several man holes 3 in total from septic tank and house, all are clear. We checked all traps too and all have water in them.

Hi Saveasteading, yes he actually spoke to the suppliers of the septic tank when he was onsite who told him the vent pipe should be lower to the ground to help with air flow ( he originally had it about 3 foot high ) now it’s about 1ft from ground but still no difference. There is a stronger smell today from outside the house today at inspection chambers so I opened them up again but everything is clear. It almost seems as if the smell is lying in the ground pipes and not getting away fast enough. I know these chambers will obviously always smell but seems stronger today. Also the smell has moved back into the hotpress where the internal soil vent is boxed in and not as stronger in bathrooms. ….very strange and frustrating!!

Hi, it goes to a septic tank/treatment tank within our site, builder checked all pipes to septic tank and the pipe that exits the tank and all are free from any blockages.

Sorry Mr Punter, just had to check what a Durgo valve was, I see it’s another name for an air admittance valve, apparently I don’t have one of these having spoke to the architect when this problem arose. He said ours is a direct pipe that is vented out at roof level, flush with the slates.

Thanks Mr Punter, if you mean was it air tested I’m not sure to be honest, ( apologies as you can tell I’m not a builder or plumber ) everything has been signed off by building control however. The soil stack has been boxed in with plasterboard maybe it should be removed to see the entire pipe ? Thanks for the reply Kevlin, just off the phone to a chap who recently built his own house he said to definitely check the toilet seals again. It just seems strange that after doing a smoke test it didn’t show any smoke at the base of the toilets or anywhere else.

Hi everyone, Hoping someone can shed some light on an issue we have with a sewage smell from our new built house. Smell comes from the 2 bathrooms but comes and goes also inside hot press where the internal soil stack is located. Had builder up recently none of the traps are dry and the smell isn’t coming from any of the toilets, sinks or showers. All manholes checked and no blockages, septic tank checked and seems to be working fine. Builder did a smoke test ( several ) and smoke is extracted at roof vent where the 2 soil vents extract from. Also no smoke came into the bathrooms/hotpress when tests were done. Very baffled at this stage would appreciate any advise or something else we could try at this stage ? The builder is bringing his plumber up next to check toilets are sealed correctly but with no smoke showing in bathrooms after smoke test not sure that’s the issue. The smell comes and goes from each of the 2 bathrooms. We have an upstairs bathroom and there is zero smell upstairs.