Winter Roost Boxes. Chickadees, owls, and woodpeckers that remain in Alaska during winter use natural tree cavities and birdhouses as roosting sites. These roosting sites provide protection from wind and snow and extra insulation against the cold. Any birdhouse can provide a winter roost site if it is properly built, but better insulated birdhouses can also be constructed. Try placing perches on the inside of a birdhouse. During severe cold several chickadees sometimes share their body heat by roosting together in a single cavity.
Position the house so its opening does not face into direct sunlight or prevailing winds. Full or partial shade will help keep the house cooler, and a more protected location will be safer. If necessary, a longer overhang above the entrance can also help provide shade and shelter. Angle the house so rain cannot easily run into the opening or through ventilation holes. Some bird house models include an angled face to ease water runoff, and a larger roof overhang can also help keep the interior of the house dry. The house could also be positioned in a more sheltered area, such as underneath the eaves of a roof or against the trunk of a large, full tree that will help protect the bird house.