Building coop. Have heat question.

[Ridgerunner]

If you provide heat and the electricity goes out, they could be in serious trouble. If you provide a well-ventilated draft-free coop and let them acclimatize, they should do fine, especially in an insulated coop. As long as it is draft-free, your biggest risk is lack of ventilation. The coop needs enough ventilation to get rid of moisture and ammonia. Those little coops can be hard to get it right though. Good luck!

These links might help.

Pat’s Big Ol' Ventilation Page
https://www.backyardchickens.com/web/viewblog.php?id=1642-VENTILATION

Pat’s Cold Coop (winter design) page:
https://www.backyardchickens.com/web/viewblog.php?id=1642-winter-coop-temperatures