[Chris H]

My garage/shop is a detached 2-car, built in the 1920's. No insulation and very basic. It is used primarily as a wood working shop, but used to keep cars it it too. My heat source is a second hand 60k BTU residential gas furnace converted to propane. I built a two stage filter box to keep the dust out of the plentum. It is only run when I am working out there, or getting ready to work out there.

My biggest problem, from the start, has been condensation. It would settle on the tools and cast iron table saw and other surfaces causing rust. My solution was to mount two very cheap ceiling fans up in the rafters. They have been running 24-7 for over 20 years, with only one cleaning and service. Admittedly, they are about shot, and need to be replaced, but the condensation issue is no longer a problem.

By the way, I never ran the furnace with cars in the garage. I have run the furnace overnight on occasion. In the winter, I was always satisfied with "sweat shirt warm" as warm enough for me for working out there. I also use a dust collector to keep the dust off the machinery to a minimum.