Drain odours inside can show a dry trap, split vent
https://tysonncnz515.raidersfanteamshop.com/obstructed-drains-in-geelong-why-they-occur-and-when-to-call-a-plumbing-company
Sewer odours inside can suggest a dry trap, broken air vent, or partial blockage; Geelong properties with big trees or older drain lines might need CCTV evaluations to find invasions and protect against repeating smells.