I am getting ready to start building my coop for this spring. I live in Michigan - should I put insulation in the walls?
I would insulate if I lived in Michigan. I live in Texas and we put air conditioners in our coops (just kidding), but we do use fans.
My coop gets the morning sun for about 4 hours and that east wall gets HOT! I'm thinking about installing a panel of foil-faced rigid foam insulation between the exterior and interior wall for heat reflectance. In my part of the state, heat, not cold, is the problem, so I don't care about sacrificing solar heat in the winter.
Is your coop big/small? Ours is 4x8, we insulated the ceiling, if it was larger we would insulate the walls. This will be our first winter, but our thinking is: The birds we will have are orpingtons, so a heavy bird and cold hearty, if we insulate the roof we won't be losing the warmth they create from thier body heat during the nights. Living in Iowa is probably similar to living in Michigan, one day it can be 30F the next day -20F. We are going to give this a try and see how it goes. If you have a larger coop I would insulate more, with a smaller coop, insulating the roof will probably be sufficient. On those really cold days we have discussed an extension cord and a warming light in the coop.... Just food for thought...
I live in Wisconsin. We insulate the coop in the late fall by collecting newspaper and crumbling them up and filling all the vents up with newspaper. For the rest of the year, there is 1" styrofoam board between the outside wood and the inside on most of the walls. We tried various things to insulate the ceiling, but the it became a place of mice to live. Now, we just go with the newspaper and then burn it all each spring. The coop used to stay about 20 degrees warmer than the outside temperature. This year, we but an addition on it that is cement block. We are hoping that works better. We use heated watering bowls made for dogs in the winter or the water would freeze solid. If we are getting temps that are seriously below zero, we have turned on a heat lamp or even a little heater. I'm hoping this year I won't have to do that.