Moving my flock, and wanting to set up a new duck house. I was thinking a wooden building 12 x 12 atleast. Hubby is thinking an enclosed metal carport with a roll up door. Anybody use a carport for shelter? I would be putting smaller doghouses, or enclosures for them to sleep in. Wasn't sure about ventilation on it, and if it would be good in the winter. I'm in NC, hardly ever snows, but it gets low teens. Will it hold their body heat in? Any suggestions, or advice is welcome, thanks.