We are experiencing random sewage smells, usually in one downstairs room and sometimes the room directly above. Sometimes the smell is outside the house too. There is a septic tank but it is not near the house. Would a smoke test be required as we cannot find any obvious leaks? The stink pipe has nothing to blocking the vent but we can't tell if there is an internal blockage. What would be the best way of finding where the smell comes from?
