I had the heater for my garage gym/ shop which was about 800 square ft. This heater is very powerful! I would use a propane heater during the colder winter months to get it to a quick high temperature, and then use the Newair to maintain. My unit had an arc on the power cord that caused my unit to trip my breaker. I notified NewAir and they sent me a new unit out immediately. I would recommend!