I live in northwest Arkansas and brood my chicks in the coop. I built in a permanent 3’ x 6’ brooder. The chicks go straight into that from the incubator or straight from the post office. I had some in there last February when the overnight lows were often below freezing, sometimes well below.
I heat one end and let the rest cool down as it will. There were some mornings I saw frost on the far end of that brooder. By tenting it in it was toasty on their end. I keep the food and water in the warmed zone so the water does not freeze. They can and will go into the colder zones, especially when they get older, but I don’t want to discourage them from eating and drinking. You have to keep one area warm enough for them but it does not need to be the entire brooder. I use two heat lamps in case one burns out and I can heat a bigger area.
By raising them in this brooder, they play a lot on the cooler end, just going back to the warm end when they need to warm up. This way, they get acclimated to the cold and feather out faster. I have had 5 week olds go through the night with the overnight low in the mid 40’s. I’ve had 5-1/2 week olds go through the night in an unheated coop with good draft protection with the overnight lows in the mid 20’s. If that coop did not have good draft protection and if they had not been acclimated I probably would not have done that.
I’ve kept 28 chicks in an old 3’ x 5’ brooder until they were 5 weeks old. They were mostly pullets and were starting to get a little crowded but I did not see any bad behavior. I also kept 23 chicks in that brooder for 5 weeks, but those were mostly cockerels. They were starting to get crowded. How big your brooder needs to be depends a lot on when you plan to take them out of it. The sexual make-up makes a difference in how fast they grow and how they act. Mine were all full-sized breeds, no bantams.
You don’t have to brood in your house if you can come up with a reasonable alternative. It does not matter what the temperature is outside the brooder, just the temperature inside the brooder. Good draft protection is essential too.
I heat one end and let the rest cool down as it will. There were some mornings I saw frost on the far end of that brooder. By tenting it in it was toasty on their end. I keep the food and water in the warmed zone so the water does not freeze. They can and will go into the colder zones, especially when they get older, but I don’t want to discourage them from eating and drinking. You have to keep one area warm enough for them but it does not need to be the entire brooder. I use two heat lamps in case one burns out and I can heat a bigger area.
By raising them in this brooder, they play a lot on the cooler end, just going back to the warm end when they need to warm up. This way, they get acclimated to the cold and feather out faster. I have had 5 week olds go through the night with the overnight low in the mid 40’s. I’ve had 5-1/2 week olds go through the night in an unheated coop with good draft protection with the overnight lows in the mid 20’s. If that coop did not have good draft protection and if they had not been acclimated I probably would not have done that.
I’ve kept 28 chicks in an old 3’ x 5’ brooder until they were 5 weeks old. They were mostly pullets and were starting to get a little crowded but I did not see any bad behavior. I also kept 23 chicks in that brooder for 5 weeks, but those were mostly cockerels. They were starting to get crowded. How big your brooder needs to be depends a lot on when you plan to take them out of it. The sexual make-up makes a difference in how fast they grow and how they act. Mine were all full-sized breeds, no bantams.
You don’t have to brood in your house if you can come up with a reasonable alternative. It does not matter what the temperature is outside the brooder, just the temperature inside the brooder. Good draft protection is essential too.
chicks but I planned on using an old plastic baby gate , lining the inside with cardboard for insulation and such and using fresh hay for bedding. Sounds like they will do great. 
