How do I know when it's time to move new chicks from garage to coop?

[NYcue]

I purchased 4 barred rocks 5 weeks ago. Currently this little family is located in large container in my garage in upstate NY. The temperature in my garage averages between 65 and 70 degrees and I do have a heat lamp above the container. The chicks are just about all feathered out but the temperature outside is in the low 30's in the morning. I don't wish to heat the outside coop and I'm in no hurry to move them out but I was wondering what would be safe temerature to make this move to the coop?

thanks!!!

 

[leonphelps]

second feathers are safest temperature.

 

[NYcue]

Thanks for the quick reply but ... I'm sorry I don't understand.

 

[KimKimWilliamso]

I THINK they meant to say that as soon as all down feathers are gone, and second set of feathers is fully grown in, they are good to go outside.