We recently purchased a home in the upper Midwest and I'd like to add insulation to the attic space. Currently there are 2 gable vents and a few slant back vents on the roof. I've read that it's recommended to add chutes between the rafters before adding insulation but I can't seem to find how much ventilation I need between the chute and outside. Currently the underside of the overhang isn't enclosed so the siding runs to the underside of the roof sheeting. There isn't any venting from the soffit. I can find 2" and 4" round louvers at the local big box store so do I use something like that? Also how do you choose which width chute to use?
Thanks
Thanks