I remember the old ice cold garage workshop before I moved to Florida. We're re-doing our floors here with a radiant heat system. I sure wish we had floor heating in the old shop. I think it would be cost efficient for a garage workshop like yours, too. I saved this site in my favorites because it's full of handy facts on the subject. You might find it useful for your application. http://www.heattechproducts.com/why-heattech