re: Spray foam insulation

I looked at this way:

Let's assume the spray foam was 10k more than regular insulation. If it cuts my bill only a $100 a month that's a 100 month ( 8 year) payback.
Now, I believe it will cut it a good bit more than that and given that energy costs will continue to rise, it was a no-brainer.

Obviously, if you aren't planning on staying in the house, you may not want to do it.