Active job

Feral And random smell!

We have an intermittent nasty sewage smell since we renovated several years ago and installed new bathroom, kitchen, laundry etc. It comes and goes And so far we have been unable to diagnose the issue further than suspecting it’s a possible vent pipe issue. We have a video of a smoke test which showed weakness in a pipe join which was thought to be the issue however that’s been fixed with sealant and the smell remains. We are looking for someone with experience in diagnosing issues such as this - if you’re up for the challenge! Please advise if there is a cost to investigate prior to actually repairing the issue. Thanks!