Our house is 115 years old. For the past 2 months, a weird smell has been coming from a closet on the second floor. It smells like skunk, or rubber-garlic. I've smelled a dead mouse before but it's not like that. It gets much stronger when the sun hits that side of the house. It's my son's closet and I figured it was some toy that was decomposing but I've taken everything out of the closet and came up with nothing. Two recent changes near that closet are: a new furnace was installed in the attic, though not directly over the closet. There's no heat duct into the closet, but a lot of duct work happened in the attic and possibly something fell into the wall? (It's unfinished attic, balloon construction). The other thing is that we had insulation blown into the stairway that runs under the closet, and there may be a leak in the siding there (we later found leaks across a different part of the house - that's another story!) and I'm wondering if it could smell. It doesn't smell in the stairway though, or anywhere else in the house. Also, we had the house rodent-proofed a year ago, all tiny holes sealed (because of rats in basement). I'd really like to figure this out without opening up lots of walls for nothing. Anyone have an idea?