My Pekin ducklings will be 4 weeks old this weekend... I'd really like to put them in their duck house, but not sure if it's warm enough. I live in Kansas, and the temp has been between freezing at night, and high of 20's and 30's in the day. Inside the duck house, there is a deep layer of straw on the floor, R13 insulation in the walls, and R30 insulation in the drop ceiling. They also have a heat light. Is this enough to keep them warm? Or do I need to wait until they are fully feathered? Included is a pic of the outside of the duck house.