I had my basement finished off about 10 years ago, into my sewing studio. I have laminate flooring that has a foam barrier under it, keeping the floor from getting real cold. He also insulated the walls thoroughly. And when I had the new furnace put in, I had them put a duct vent in that would heat (or cool) the entire room. It works wonderfully. I would not want a wood burning stove in a sewing room. The fabric will soak up the wood smell. I used to have one of those oil-filled heaters that I kept near me, but didn't like the oil smell it gave off. There are now ceramic heaters. Check with one of your home improvement stores, on what they think would be best for your situation.