Just recently Fall 2003) had a home built. My garage is not insulated. I went up the attic access in the garage and I noticed that there is no barrier dividing the first floor and the garage. Off course that part is insulated but I'd imagine a lot of heat would be since there is no drywall seperating the garage and first floor.
Answer:
Neither do you want any separation there. The more access there is for air movement up there the better. In fact, I often recommend to people that they remove that door from the garage attic entrance and replace it with a framed screen to get rid of various gasses in the garage and get even more air movement going. The ideal situation would be to have the temperature in the attic the same as it is outside. We'll never reach that of course because no matter how we insulate, there will always be some heat lost. By the way, you need a screen there to keep vermin from nesting in the attic.
