One nice thing about Hydronic heating is you don't get a large temp differential between floor and ceiling. My 22 ft vaulted ceiling peak is within 2 degrees of the floor temp. I put two fans in my shop and have never turned them on. Another thing to consider is insulation. I have R40 walls and R60 ceiling in my shop. I can usually turn the heat off in April and just rely on solar gain through 4X6 foot windows to keep it warm all summer. Not cheap to build but saves money in the long run. If I had a hanger I was planning to own for 30 years and was going to heat in cold country that I was going to keep for warm and be in daily I would price out the cost of replacing the slab with in floor heat. If I was only going to be in it a few weeks of the year I would get warm clothing and plan most of my work in the summer. DENNY