Personally where I live I feel that giving the birds in my coop artificial heat would be wrong. My goal is to allow the girls to acclimate to their surroundings. Living in cold weather climates, the birds will grow extra down, learn how to fluff and as long as you have a perch that is large enough so the girls can drop their feathers over that middle longer toe. If they cannot, then that toe will be to cold and freeze.
Also deep litter method is the best for winter, it produces its own "composting" heat. May not feel like much to us.
As an example, you have that heat lamp so your coop is a nice even 60 degrees, nice...and then a snow storm comes in, takes lines down with it, you have no electricity. Hmmm, what happens to your chickens? You can bring them in the house, but your not going to have heat either unless you have a generator etc etc.
Don't start something that you may have to be very concerned about later when its taken away.
Just food for thought...