A building in rural lowa is kept at 75 F when the outdoor design temperature is 20 F. If the building envelope has an overall heat transfer coefficient (the combined U-factor value for the walls, windows, roof and other building components) of U = 0.06 BTU/hr-sf-F, and the building dimensions (length x width x height) are 20 feet X 50 feet X 12 feet, calculate the heat loss through the building envelope and roof (ignore heat loss through the floor).