My brooder is in the coop so mine are out of the house as soon as I take them out of the incubator. If mine are hatched by a broody hen, they start out outside. But you do it differently. Nothing wrong with that. We all do things differently.
When you can take them outside and leave them depends on a few things. You’ve already covered one with the draft protection. What are your overnight lows? If they are in the upper 70’s yours could probably go out now. In the upper 60’s wait another week or so. If they are below freezing, I’d wait at least three weeks. There are other factors though.
How many do you have? Two or three have more trouble snuggling up to each other and staying warm than 15 to 20.
Have they been exposed to cooler temperatures or have they lived their life in the topics? It’s rough going straight from really warm to pretty cold, no matter how we dress. If they are exposed to cooler temperatures they feather out faster and acclimate better. Maybe a few supervised visits outside while you can watch them during the day. If they start showing signs of being cold, take them in and warm them (Plaintive peeping and just standing around. Maybe huddling together. If they are active and running around they are fine.) This not only helps them acclimate it will boost your confidence in actually seeing how well they do handle the temperatures.
My 3’ x 6’ brooder is in the coop. I warm one end and let the far end cool off as it will. There are times I’ve put chicks straight from the incubator in there with the temps below freezing. The end they are on is pretty toasty but the far reaches may have ice in it. They are really good at self-regulating even straight out of the incubator, but after they get some age on them they venture into the far end, especially when it is a bit warmer. But the important thing is that they are exposed to colder temps so they acclimate really fast.
Now some of my experiences with raising them outside. In a ridiculous heat wave a few years back I turned the daytime heat off at 2 days, the overnight heat off at 5 days. Their body language told me they did not need the heat and they did not. Man, was it hot.
I’ve had five week old chicks raised in that brooder go through nights with an overnight low in the mid 40’s in my unheated grow-out coop. There were around 15 or more of them, they had really good draft protection but also good ventilation high overhead.
I’ve had chicks go through nights with the overnight lows in the mid 20’s Fahrenheit before they were 6 weeks old, with the other conditions similar to the last story.
I’ve had a single chick 4 to 5 days old get itself separated from the broody hen spend the entire day by itself with the lowest temps it saw probably in the upper 70’s, maybe lower 80’s.
I’ve seen a broody hen take her chicks to the roosts at two weeks old when the overnight lows in the mid 70’s. Not all the chicks could get under her for warmth.
It’s not a simple question. My conditions are different from yours with mine exposed to the environment from Day 1 so my answers will be different to yours. But they really can handle cold a lot better than many people think. I’ve seen it.
