I have 25 meat birds in my garage that are 2 weeks old. Yes they are smelly little things but they are in the garage(non attached). They are now getting tail feathers and some on their bodies. I live in Central Michigan. The weather is warm during the day but here lately the temps at night go down in the thirty's sometimes a little frost on the ground. The gaylord box in which they are in is getting a little small for them now. My dumb questions is: If I give them a pen with a shelter about the same size that they are in now with a heat lamp will they be ok at night when it does get down in the low thirties? I don't want to kill them. Just give them some more room durning the day with out having to move them back inside for the night.