Shop/Garage Heater suggestions please

I would work with what you feel is the best for you. I would go with an electric heater, put it on top of your loaf that you have. Run your duct work up high down the center, and feed it off where you think it needs to be. Ceiling fans are a plus, reverse the rotation during the hot months.

This is a picture what I did for my shop, a little more then 25,000 cu.ft. heated by a second-hand house gas furnace. I don't think a drop ceiling is necessary in your case. I had to go with either gas or electric, the electrons needed to heat this shop would be costly. My insurance would be double if I went with oil or wood, or anything that required, feeding the machine. There is nothing better then just walking to shop wall and just, turn up the thermostat.

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