I knew that it would work, because I had a similar situation, but with a slightly smaller workshop area, in one of the old timber frame barns that my great great grandad built. My workshop was under the loft, had a 7 ft ceiling, and was 12 ft wide x 18 ft long. The loft floor/shop ceiling on that one had 2 layers of 1" chestnut, as did the exterior walls. The interior walls used a single layer of 1" chestnut. I heated that with a big, round kerosene convection heater. It worked ok when the temp was above 30, but had a hard time keeping up when it was colder. On average, our winters were much colder back then. That shop was made from the old horse stable where my grandfather, great grandfather, and great great grandfather use to keep their teams of draft horses. The old barn was 36 ft wide. There was a grainery under the loft, behind the workshop (also 18 ft long), where we kept wheat and oats. I still have the old kerosene heater, but it was always smelly, and a pain to light and keep clean. The cheap little propane heater is much nicer.
The old shop was tough to work in because the concrete floor was cracked and crooked, and the ceiling was too low. I did like the old hand-hewn beams though. I was able to salvage most of them and I was able to incorporate them into the workshop/loft of my new metal pole barn. I am currently in the process of dismantling a 2nd barn, identical to the first (36 x 46). There seems to be good demand for that old unpainted, weathered chestnut siding, and the hand hewn beams. When the weather cooperates, I have been stripping it off and storing it up in the loft of the new pole barn. A friend is coming over to get a truckload of it tomorrow.
I would have liked to save those old barns, but the roofs were going and the foundations were bad. It would have cost several times more to repair them, than the cost of the new metal pole barn. The new workshop does feel a bit like the old barns because that was the source for most of its material (except for the nice, level, crack-free poured concrete floor).