I am in Northern NJ. That is why I showed you how much I have open.
They chickens don’t really care how cold it is as long as they are out of the wind and nice and dry.
You achieve dry by having lots of ventilation to let the moist air out. And you achieve out of the wind by having the ventilation mostly above chicken-height.
The hot moist air that the chickens create rises up and goes out of the high up vents at the front and cool fresh air gets sucked in from the lower vents. And the chickens are happy in their fluffy down jackets.