Here is some advice I got from @Dawn_SD Hope this helps. I am going to insulate my hives and build the quilted roofs for my hives. I like the ones from the article because of the venting on the sides. Without proper ventilation this leads to moisture buildup.
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Rusty Burlew has some comprehensive advice here:
http://honeybeesuite.com/how-i-overwintered-ten-out-of-ten/4
Personally I wouldn’t open the screen of the bottom board, but she did it successfully for a few month, presumably to deal with any condensation. It seems that her husband (an energy conservation expert) persuaded her to close the screens back up during the winter. -
In addition to a quilted roof, I would consider putting insulation around the outside of the hive. You can either buy this from a beekeeping supplier, or you can make your own by cutting rigid home insulation to shape: http://www.homedepot.com/p/R-Tech-2-in-x-4-ft-x-8-ft-R-7-7-Rigid-Foam-Insulation-310891/2025328563