I live in Michigan gets down to 0 at times. I am concerned about dampness 5 chickens small coop 4x6 Plus what is the thought on locking chickens in at night during cold weather to cut down on drafts.
Unless the run is 100% predator proof, they should be shut up in the coop each night. The pop door is usually positioned low enough that any air that comes in will not directly hit your birds, unless the roost is low to the ground and right in front of the door. If you aren't sure if you have enough ventilation, go ahead and add some more. It's hard to over do ventilation as long as it's well above roosting height. Keep the bedding clean and dry as best as you can, even if that means changing it daily, to help reduce moisture.
This guy had a great idea for ventalation, just a triangle cut out with metal wirescreen at the peak, and a draft that pulls in from the first story... https://youtu.be/H3YGdxOdxS4 looks like it would work great, and an automated door!
