Thank you. Good point about covering the north side too....something to consider.@NewbieMNWelcome to our thread
Take all of this with a grain of salt, it is just what works for me.
In a coop that size, I would go buy some sweet PDZ from Tractor Supply. Place in on the floor under the pine shavings (poor it right on top if they are already in there, it will fall through), an inch or 2 deep, this will help remove some of the moisture from their small coop.
Make sure all the ventilation is high so that it doesn't go over them from low to high, as in through a chicken door (mine got frostbite due to that).
Put heavy clear plastic around their run to block the wind and increase their living area in the winter, they will spend more time in the run decreasing moisture inside. Also, the plastic it keeps the moisture out of their run (snow and rain in the fall) and you will not have to shovel it out.
If you want to, you can place a flat panel heater, I have a cozylegs heater, (now they make them for coops). I only turn it on when it is below zero, it just takes some of the edge off and seems to keep it drier in there (my henhouse is 4x6 or so). A couple of years ago it was -34F outside, with the flat panel heater it was 7F
Water outside in the run is good.
Block off any vents on the north and south sides (north for sure), I only have vents on the east and west, high up, in the winter. My henhouse is taller (I can stand up in it so about 5.5 feet). so I place a green house panel above their roost to keep their warmth in, but it lets moisture out up through the vents. you probably don't have room for that though. you can see my coop and henhouse if you click on "My coop" under my photo.
My 0rpington and Golden Comet got frostbite on their combs the first year before I learned any of this.. I think I will only get birds with small combs from now on though, as I felt so bad. My EE and SLW's were fine...
Welcome, and good luck!