Thanks for the update. I'm curious how much you think it costs you a month? I would think $125 a month wouldn't be too far off. Someday I hope to finish my garage and get some heat out there.
Tracs what is your friend doing with his 6kw boiler he is taking out? If it's priced right it may still be worth a try. I would get a quote for upgrading your electrical system for the house/garage as well.
A buddy built a pole shed just in time to experience the polar vortex last year. It's a 60x40ft with I think 18 foot walls or around 43,200 cubic feet. I talked him into upgrading his insulation a little bit from what the builder usually does. 2 inches under slab and on perimeter, 6 inch bat...
A lot of in floor heat set-ups in southwest Manitoba use the Lion brand of electric boilers. I don't know anything about prices but they are manufactured in Winnipeg which may help down the road for parts/service etc.