As the colder weather draws in, a chicken keeper has the dilemma as to whether to insulate the chicken coop, or not. Unless you are living at the Arctic, chickens can tolerate pretty cold temperatures. Each hen comes with its own built in feather quilt. Extra heating is only needed for young birds that are not fully feathered or possibly ex battery hens until they feather up. Provided they have plenty of straw they will all huddle together to keep warm. If you insulate the coop with polystyrene any crack or gap could be a place that red mite would get in, birds will peck at the insulation and come June you are going to have a hot stinky chicken coop.
Some literature advocates installing underfloor heating in the chicken coop, by providing an electric blanket. Issuing hot water bottles at night to each bird as they go to bed. If it has been raining, drying each bird off with a hair drier before putting them into the shed. Installing an extra radiator circuit to your domestic heating system with rads inside the shed!!!.