Okay, I don't have any mice problems.Make sure you are very fire and electricity consious when you introduce a heat lamp. Put everything outside their reach and away from where mice or other pests could mess with it. I've heard horror stories about coops burning. If we didnt get below 0F, i wouldn't have one (we are supposed to hit -20F this week). If you can't avoid mice completely, you can run pvc pretty cheap to protect the wires. Just being the voice of caution.
Thanks!