New build house smell

[Dobson]

Hi, we just moved to a new build. There is a dreadful 'sewer' smell in the house. No outside soil stack. AAV is sited behind bath panel in family bathroom upstairs. Had this replaced as plumber thought may be faulty, no change in smell. We are one of three houses and there is a joint pump station to the main sewer. There doesn't appear to be a vent on the pumping station, should there be? I have read advice and put all the plugs in downstairs sinks and covered with water to form a seal. This does seem to have stopped smell but obviously not answer to problem. Can't get builder to take notice! PLEASE can anyone advise what the problem could be.

 

[Chester]

Sweet baby Jesus

 

[Josh89]

You could have another waste pipe concealed behind kitchen unit. If there is space for a washing machine but you have never connected it up. Then there will be a waste pipe with a trap where the water would of evapourating preventing it from doing it's job of keeping sewage smells out. Most bew builds will have two spaces for dishwasher and washing machine. I know you mentioned that smell stopped when plug on kitchen sink but that could be a coincidence and plus kitchen sink trap looks fine and you hadn't covered overflow. If there is space where another appliance cab go then check to see if the wooden panel as a small hole cut out for drain and water inlet can go. You will be able to remove panel by undoing screws. Hope this helps