SunRise Solar makes a variety of solar powered attic ventilating fans that can be used on any style or size roof. Ventilating an attic lowers cooling costs, reduces heat and moisture in the attic, saves money and CO2 emissions, adds to the life of the roof surface and the HVAC system and because it is solar powered it costs nothing to operate and qualifies for a 30% federal tax credit. They are American made and have a 10 year warranty.