My hens, Buff Orpingtons which are a year and a half old, are halfway into their winter molt. It is supposed to turn cold this week with temps falling into the low teens at night. They have lost a lot of their down feathers. I have a flat panel heater installed on the wall near where they roost. Last year I only turned it on when temps fell below zero. Should I turn it on with the low teen temps because they are molting? Opinions, experience, anyone???? This is my first molt experience. I have four hens. Thanks for any advice.