SoundMods wrote:
One thought would be to just keep the Kenwood energized.
Or -- insulate the garage aggressively and install a 5-kW horizontal unit heater. With at least R-19 the 5-kW heater (approx. 17,000-btu/hr.) should be fine.
When the garage is not occupied you can set the thermostat to some minimum -- say 35-degrees F. A 30-amp. circuit and #10-awg Romex should get the job done.
That way your wood-working equipment will be closer to the desired operating temperature.
My two cents.
BTW -- I live south-east from you in Parkville.
With all due respect, can the HUH idea, unless you have lots of disposable income burning a hole in your pocket.
While the Kenwood should survive the temperature extremes just fine from an operational standpoint, my concern would be corrosion from condensation in repeated heat/cool cycles. Not just for the Kenwood, but for your power tools as well. Ask me how I know!
You are on the correct path with insulation first. Make sure it's a sealed up room. Ensure that the attic space is insulated and (not knowing whether you have open rafters or a ceiling) relatively air tight.
But the room does need to be at least moderately conditioned, mostly for your tools' and projects' survival. One of two approaches should work best. PTAC or mini-split.
Heating with electric resistance heat is incredibly expensive. 3.414 BTU/watt is as immutable as 12":1' Forget it, use a chemical heat transfer system (unless you want to use propane or, if you have it, natural gas). But, if electricity is the only practical power source, then a heat pump is the way to go.
PTAC is cheaper and easier to install, you see them in hotel rooms, under the windows. Packaged Terminal Air Conditioner, is the name used regardless of whether or not they also heat. Choose a unit which is also a heat pump, and not just one with electric resistance heat. That gets you nowhere.
The reasons to use a mini-split (look up "Mr. Slim") are ease of installation (no huge hole in the wall with framing) and efficiency. The SEER numbers on a mini-split are going to be
much higher than the PTAC. Modern mini-splits also usually don't even need electric resistance back-up heating elements such as are contained in most whole house HVAC systems, PTAC and window shaker units.
This means lower operating costs due to the lack of a defrost cycle (when the compressor and the electric heat are on simultaneously!) and emergency heat.
You'll want your work and yourself to be cool while working in the summer, so you're gonna have to add A/C. Might as well provide heat as well.
Typical PTAC:
http://www.heatandcool.com/ptac-air-con ... AvuV8P8HAQMr. Slim:
https://www.google.com/webhp?sourceid=c ... m&tbm=shopGood luck to you!
Stuart