Expert: Julia Booth - 9/3/2008

Question
I had a small outside opening in an attic eave.  A wild animal expert said that he did see some guano up there and I should have the hole closed.  I recently had my house painted the last week in August and closed the hole.  The first time the hole was closed, something tried to get out and the painter removed the screening.  The next day he put the screening back up in the morning and when I did not hear any activity in the hole all day long, he sealed it at the end of the day.  Prior to sealing the hole, I did hear bird chirping when I was up in the attic.  I no longer hear any sounds, but when I went up in the attic today near the eave where the gap was, I could smell a faint ammonia or fish smell.  Can you tell me what this smell is, if it will get worse and if I need to do something about it now.  I live in Providence, Rhode Island.  Thank you.

Answer
I'm sorry I have no way of telling you for sure what is in your attic. The smell makes me think that something died up there and is in the process of decomposing. It could be a rodent, a bird, or a bat. If the hole is truly sealed, you shouldn't be smelling anything there once the decomposition is through. For a small animal, about a week or two tops.

I once had a mouse die in the wall of my house and smelled it for days.

Hope this helps,

Julia