Jay J's radiant suggestion. I just had a thought! If you installed radiant (hydronic with heat transfer plates, I'm a purist) you could leave the insulation off the garage ceiling, and heat below too. You could fire the little zone from a small gas or electric tankless water heater!!!! I wonder where that flash of inspiration came from. I think JJ set it up for me to fall in to. Best of luck, whatever you do. Regards and happy new year to all. Tankless Brian & Autumn. (My 3 1/2 yr old's interested already)