Something smells awful! Dead animal in wall? Help!
Every so often, we get a very bad smell always coming from the same place. It seems to be in an unused upstairs bathroom. It comes on suddenly every few months - within a day is TERRIBLE - stays bad for a week or so and then faces away. I have tried pouring water down every drain. No impact. I think it may be animal getting into wall and dying. The bathroom has 2 exterior walls, one of which is party wall with the garage.
Is there any way to investigate the animal theory without tearing out the wall. We definitely live where anything from a mouse to a possum might seek refuge in the winter. I never hear an animal scratching but we have found evidence of mice in the attic and basement. The dog doesn't seem to pay attention. It seems like it *might* come from a heating duct in the bathroom. It is always in the same area. It smells stronger than a sewer smell when it is a fresh occurrence (it is awful) then it will go away for months, then 3 or 6 or more months later it will reappear.