I think you should be ok. The heat lamp bulbs are red and the babies are ok with that.
I have a red/orange light that I bought when the girls were babies. It provides some heat. If I use that to warm the coop this winter, will that keep the girls from sleeping?
You can use that if you deem it necessary I think you will find that as long as you have shelter and the direct cold wind off your birds they will be good, but if you do close up the coop to use the heat source please make sure you don't have it air tight always leave a vent for air exchange(I know it sounds ironic but it is better this way) the southern most wall with an opening at the top will suffice here. O2 in CO2 out is a must plus they create a lot of humidity from their excretions and normal respiration this causes more problems for them than plain cold air, in this part of the world. LOL
Jeff
In my open coops, I will sometimes run the heat lamps out to the yard. I'm a whimp and I don't want to see my birds cold at night.

