I live in north east UK, it is currently -7 *C.
I have 5 hens and 2 coops, one coop is just an emergency one as sometimes the older 2 won't let one of the young ones in the original coop so she has somewhere to go.
The main coop is just wood, it does have a slide I can pull across to provide ventilation though I close it when it's this cold and I don't think the coop is too drafts for them.
All 5 of them huddle together, usually 4 are crammed in the small nesting area!
This morning it took me ages to open the door as it was frozen shut
Has anyone any tips - not including heating lamps/bulbs/bowls to stop water and the door from freezing? Isn't there a safe substance to apply?