Aart, hope you wore a N95 dust mask when you dusted those birds. I didn't once, and it was a bad experience, with months of an asthma flair-up, meds, etc. Ugh! I never had a bird freeze, even when my first d'Uccles roosted in the barn rafters. A roof and wind protection will be fine, if you select breeds that do well in the north. Predators are the big risk, and my coop is now Ft' Knox for chickens. Mary