Depends on the breed and temps. I know stupid. I live in tn. I use a red heat lamp at night. I have light bodied leghorns (8), a Rhode island rooster and a small polish cross of sorts. My coop is not huge. And completely closed at night. I don't start the lamp till dec..and I run it as long as it's 30 or lower at night. I do not run it during the day unless there is snow or rain in the winter. However heavier breeds like say an Orpington or a jersey giant, etc..won't need a lamp till lower temps. Ventilation is important..it lets out humidity. Keep things as dry as you can. And another tip..if using a heat lamp; make sure it's clamped to something solid and screws are in the middle of each Handle/clamp so it won't fall..I know that's a bad explanation...if a chicken bumps the lamp..bad things happen..the screws(long ones) basically act as something for the lamp to hang on if it falls off it's mounted place. It's plan b and it works. I'm a firm supporter of heat lamps at night.
So question one , what temps would you have to worry about ? Question 2 , how do you have a coop that is vented but not have drafts ? With a vent would it not let in a draft ?
Vents are placed in the TOP of the coop..they do not have to be huge either..the vent should be above the highest chicken head ..and as close to the top of the roof as you can get..never in the floor. Also make sure to have chicken fencing over the hole so a predator can't stick a hand In..(raccoon)
My girls very rarely see anything as high as 30°F from mid-December to late February. My original 12 included 2 Cubalaya. You would be hard pressed to find a breed less likely to be termed "cold hardy", they did fine in temps that occasionally went to -20°F.
Id never heard of the breed and looked them up...they are beautiful..
