We live in central MA and are already having 30 degree days and 18 degree nights. Our 10x18 garden shed was converted to a 10x10 coop by building a knee wall and topped with chicken wire. The other side is for supplies. The shed sits 1 foot off the ground and has 2 gable vents. Also, the shed is about 8 feet tall. Should I: 1) stack hay bales around the ground opening to keep out cold 2) put plastic over the chicken wire divider. I'm waiting for a water heater and use a night light but no heat. My 6 gold lace Wyandottes (the sweetest girls in the neighborhood) are 6 months old and giving me 4 eggs/day. But I'm worried about winter.