I have a detached garage that I do a lot of work in it is around 24’x24’ then there is an open sided car port around 12’x 24’ and then a workshop room addition of 14’x 14’.
At my old house I had something similar but a bit smaller and I put a wood stove in it that was almost useless. If a building is not insulated first off and then kept heated full time it is really hard to get it warm enough to use when you need it. I would go out on the weekend at 6am and build a roaring fire in the stove in the non insulated garage go in the house and eat breakfast and go back out around 8am and it was still stone cold. The floor and everything being cold was a lot of mass to heat. I would work on the fire for a bit and then mostly stand around the wood stove staying warm. By noon it wasn’t warm but warm enough to be wrenching a little with a coat and insulated pants and gloves. By 4pm it was really nice like you would like and it was time to go back in the house. If it was the weekend I would sometimes stoke the fire up and go in the house for the night and by the next morning it had went out and I was pretty much starting over.
Knowing this when I bought this place I closed the 14x14 room off and insulated the inside with 6” of foam and then covered that with .5” plywood and that room is a small workshop and tool storage room. I heat it with a two burner radiant propane heater that I run off 20lb bottles and I also have a small electric cube heater. Now I go out at 7am and by 8am that room is nice and warm and my tools are also warm and many jobs I can do in that small room. If it is a bigger job it isn’t as bad with working in the cold as I have a place to go and warm up.
I have a friend that has a large insulated garage with a lift and it is his business and he has in floor hot water heat and he keeps it 70 all winter but the concrete floor is about 80 and it feels so good on your feet and is a pleasure to lay on even when working in there. I’m lucky enough I can use it during his off hours in a pinch.
If you really have a lot of wood to burn and plan on using the shop a lot I would highly recommend an outdoor burner with in floor heating and a good insulation job. Gets rid of the fears of having a fire in your shop and also all the smoke and such with it inside when you open the door.
Here is a panoramic shot of my small workshop room. The heater is under the rolling rock sign and next to my DIY insulated door to the main garage. Welcome to the forum.
