I bought this unit 2 yrs ago. Garage is 22X24.. I set it about half way for the Chicago winter. Enough to melt the snow on cars and water not to freeze on garage epoxied floor. Also have had gatherings in winter when converted to the Bar-age. Heats well enough to entertain. I do have a ceiling with storage above and my walls are insulated. Con: wish it had a visual temp/ thermostat setting.