When to remove the heat?

[zchickens]

I have a small group of 9 week old chicks (3 white orpingtons, 3 blue copper/wheaten maran mixes), and I am unsure as to when I can remove their heat lamp. It is very cold here (was -17 F last night, overnight lows have been ranging from -18 to +15 F at night), but they have been in the barn for 3 weeks now, and don't seem to be bothered to much by the cold. I don't want to remove the heat lamp too soon, but by the same tolkien I have a group of 11 cream/gold brabanters that are 6 weeks old now, and need to be moved outside soon (my indoor brooder is getting to be a bit small for them). With two heated waters and one 250 watt heat lamp already going in my barn, I am not sure that I can burden my one outlet in my barn with any more lamps; so I don't believe that adding another heat lamp is an option. Thanks!

Z

 

[americana-chick]

wll lets see... could you make a brooder? one like this except just use one heat lamp in the middle? http://i54.photobucket.com/albums/g97/drewc_andy/brooderbox.jpg
i think it might be to cold for them... are they fully feathered? if so you could gradually take away the lamp slowly. just a thought. hope this helped!
~Bri