Join Date: Jun 2010
Location: central Minnesota
I think you would be better served to go with horozontal units hung above the work areas, or at least one horozontal unit hung above your main work area. Radiant heat heats the objects in the space and not the air and I think that you would have to be fairly close to a verticle unit (if it isn't fan assisted) to feel the effects.
What ever you decide the best thing you could do is to insulate the shop. Even getting just poly on the ceiling will help keep the heat in.