I have a 5 month old pullet that has been in the house since hatching. The last couple of months she roams the house w/a diaper on. I'd like to kick her out into the coop w/the rest of them but the cold weather concerns me. Will going from a 72 degree house to a 20 degree coop cause a problem? I will of course give her a fenced area w/a heat lamp until she is used to the coop. Is that good enough or should I wait til the weather warms a bit?