I use a pellet stove in my shop 28 by 40, 12 foot side walls. works good so far, today is -10 and it dose fine on # 1 setting keeps it at 55*. yea I know it sounds to cold for most of you but it feels real good to me. living up here in the cold weather you get use to it and when it warms up to 30* above you can go out side in a tee shirt and shorts and stay outside all day. if you don't believe me ask my friends up there in Canada.