I'm having spray foam installed in the basement in the next couple of weeks [around the rim joist and in between the floor joists] and I'm curious what to expect from folks who have used it. I've heard only great things about it. When we moved here three years ago there was pink insulation in the basement ceiling. Quickly discovered three problems: It wasn't particularly effective. We have an old house and mice found it to be a nice hiding/living spot The basement gets a bit humid in the summer, and we keep our cat litter down there. At times the cat pee smell tends to waft upstairs. [I'm convinced that the smell had actually gotten in to the insulation, much like your clothes pick up the smell of cigarette smoke when your in a bar]. I'm led to believe that sealing the rim joist will be huge, especially for a house built in 1910. I'm hopeful the spray foam will also help with the other issues - as well as reduce the humidity since less outside air will be getting into the basement. Thoughts? Opinions? In case you're wondering, I'm paying $1,700 for two inches of closed cell foam for an 820 square foot area. I'll be getting a $300 rebate from my local utility, too.