Gas and Oil Home Heating Furnaces - Garage Heating Question

I have a question for all of the HVAC experts out there. I'm turning one of my three bays in my attached garage into my workshop. The whole garage is 32 x 22 x 10. I'm planning on using a curtain to separate the third bay for dust control (not that it helps heating, but just trying to give the whole picture). Garage doors (16 x 8 and 8 x 8) will be insulated with 2" foam. All walls are R11, one wall (32') adjoining the house and heated living space is above the entire ceiling of the garage.

I want to add a garage heater, but have no idea what size (BTU/h) I need. Does anyone have any estimate or any ideas? I've tried a few online BTU calculators, but the estimates are all over the place. I live outside of Detroit, so it can get quite cold in the winter. I'm not looking at working in shorts and T-shirt in the winter - just something to make it bearable for a few hours at a time.

Thanks!

-12VMan
twelvevman@yahoo.com

I will tell you the exact heater to get. It is 75,000 BTU propane or natural gas heater. It hangs down from the ceiling. Very efficient in fuel consumption. Terrific on putting out heat. My garage is 32 x 44, and it is toasty warm even in 40 below temps. Good Luck

Shop around at some of the furnace company's there. they have old furnaces units that they take out that are good and use one of them. They have a better blower in them than a unit heater does. So its a little bigger than you need if its to big plug a orifice.You can also make aplenum on top of it with damper blades to put the heat anywhere you want. Just put it on a stan up off the floor about 2'. This is for code, here its flame 2' up off floor, and it will get the cold air off the floor for you right into the bottom of the furnace.This way you will have a faster pick up when you go out there. We always have a list of people that want a old furnace for just this.;) ED