Be very careful using a heat lamp in a small coop..every spring BYC has several threads started by people who had coop fires. I raise chicks outdoors in the run when our springtime temps are in the teens and twenties and I won't have a heat lamp within miles of my setup.
32 is not really cold, especially if you have breeds or varieties that are suited for colder weather. We will see 22 below zero for the overnight low on Friday night with more snow. I don't heat or insulate. I know I risk being called a "tough bit' but that's the way I do it. If you want to provide heat (and it's not necessary for most chickens as long as they are kept dry and out of direct drafts) there are much safer alternatives, like a Sweeter Heater or other small heaters that give off just enough radiant heat to keep the chill off, and they attach directly to the wall of the coop. Bear this in mind - a heat lamp does NOT need to fall directly into the bedding to start a fire. Especially in a small coop, dust can accumulate on the bulb or housing and that can get hot enough to burn. Chickens can panic and fly into it, and their feathers are flammable as well.
So please, if you are going to heat, be sensible and avoid a heat lamp at all costs. And be prepared with a plan B for power outages. Good luck!
