Thanks for the posts on overwintering in a building. Mark asked for some comments but I suspect that Mark is actually using a much simpler system. There appear to be two ways to winter bees inside one "high tech" with fans for ventilation and air circulation some heating and even cooling the other "low tech" involving limited ventilation and often some type of flight through the wall arrangement. Both work as long as the needs of the bees are met. Any unheated shed will provide excelent wind protection for the colonies and allow the beekeeper to monitor and do simple management such as some feeding if needed during the winter. Don Jackson from Pequot Lakes MN has written some articles published in Am Bee Journal and Bee Culture on his low tech wintering building and methods which work very well for him in central MN.
More than one way to keep bees alive over winter in the north.
FWIW
blane
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Blane White
MN Dept of Agriculture
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