Hello, I am planning on putting blow-in insulation over the existing (and thin) batts in my attic. I know that normally I should use baffles to keep insulation from covering soffit vents, but I can't find any vents except for the single attic fan. I posted this video on Youtube that explains it pretty well: [url=http://www.youtube.com/watch?v=3Rv-hFPLQiI]Baffles or not? - YouTube[/url] So do I need baffles? Do I even have any ventilation? What's the best way of doing this before winter shows up? Thanks very much!

Hi. This is my first post on here and I am not overly experienced in house building so please forgive any silly questions I may ask. I am having a new house built in Northern Florida. The prices from the contractor for having the walls and roof insulated with spray foam were way too expensive but I really want it done so am thinking about DIYing. We are having the house built in stages so I would have the freedom of being alone in the shell to do the job. I am thinking of either using the DIY kits like those available from Tiger Foam/Graiger or using the rigid foam board with reflective backing cut to fit between the studs/rafters and held in place with spray foam from a can/gun. I was wondering what the general consensus is about which of these options is best in terms of price and efficiency assuming a 2x1" layers of board or a 2" layer of spray foam. My main queston is this; if I used 2x1" sheets of rigid foam board with a 1" gap between them, the edges sealed by spray foam to hold it all in place, would the air cavity provide a significant enough added insulation layer to make it worthwhile? Thank you gentlemen (and ladies).