I'm a bit confused. It sounds like you have eggs under a broody in your house that you expect to hatch in a few days. Is this right?
Edited by Ridgerunner - 7/5/11 at 5:43am
Chicks with a broody can go outside as soon as she brings them off the nest to eat and drink. I usually give them a day or two in isolation so they can learn to eat and drink on their own without interference from the other adults, but many people do not do that. I'm just over-protective. Mama has a built-in heater and the power never goes out. I see you are in Ontario, so your nights are certainly going to be cooler than mine, but if you have a broody, it does not matter.
If they are in a brooder without a broody hen, they should be fully feathered at 4 to 5 weeks old. They can go outside without any supplemental heat when they are fullky feathered.