My "shop" is my garage. The first house I built I used a high efficiency water heater for the home and ran a fan coil unit with the hot water for the garage. Worked fine but you had to preheat the night before. The house I am in now I was lucky enough to have natural gas. I bought a garage heater from Granger (hangs from the ceiling) and turn up the heat when I want to work out there. This setup works great and is safe.
