We are finishing the attic space over our garage. The room will end up being about 12 X 12 with a 4 foot knee wall and cathedral ceilings about 10 feet high at the peak and a 4x5 dormer off one side. The contractor is suggesting a Sanyo Ductless Heat Pump for heating and cooling. I told him that I thought those didn't really work below 40º. He said they make a new unit that does work in cold climates. Perhaps he is talking about the one with a back up heater. We live in New York just north of NYC. He says a house he worked on in Yonkers uses the Sanyo system for a room over the garage and it is working great this winter. The past 2 weeks it has been in the single digits (below 0 with wind chill). I'm skeptical. Has anyone heard of a ductless heat pump working in below freezing weather? Is it efficient?