During freezing weather I protect my rabbits from the elements. Tarps are placed on the north and west walls to break the wind. I use water bottles, so to keep the metal spouts from freezing I string Christmas lights directly next to the spout. The older, large style bulbs generate just enough heat keep the water from freezing in the spout. The water in the container may become slushy at the top of the container, but the rabbits always have fresh water flowing.
Note: you MUST make sure no wires are accessible to the rabbits or they will reach for them, chew them, and electrocute themselves!
This years first litter are now 5 weeks. They are currently sexed at 5 doe and 2 buck. Of course, the sex change fairy has been known to visit. REW doe, fawn buck, 4 ermine doe, ermine buck. All the ermine have varying shades of blue/gray in their eyes.