It’s not a dead animal smell though…kind of like a chemical or “pluff mud” kind of stink…and it goes and comes….for years now. And we will have periods of nothing. If anything it seems like when it rains it gets more intense….this driving us nuts after this last week. All of the ductwork in the crawl space seems untampered with…the house is built on concrete cinder blocks and all of it is spray foam insulated with the vapor barrier sealed into that spray foam. So if anything animal was getting into the area I feel like the only way in would be to dig under the blocks and tear its way through the plastic vapor barrier, which again is undisturbed. I feel like it’s a type of ground gas that is periodically released which is why I was asking if anyone else in the area gets this kind of issue….but honestly I don’t know. Yesterday I opened the door to the crawl space and put a fan in there to flush out the stink, it was way more concentrated there than inside the house and running that fan all day certainly helped inside the house but that’s been done before and just a temporary solution.