Hi Robyn, welcome to BYC and the Michigan thread
My coop is insulated, as much for summer heat as for winter. I do think it delays eggs from freezing a little. If your coop is properly ventilated it will not likely raise the temp inside, though. If you can keep your water outside the coop that will reduce moisture, a big contributor to frostbite. Those breeds are all pretty cold-hardy and should not have problems with your area's winter temps.
When pullets first start laying it takes a little time in some for the egg-laying process to catch on. Most pullets revert to single yolk eggs pretty quickly.