Roof ventilators exhaust unclean or polluted air away from the roof, including odors, fumes, and grease vapor. These exhaust fans circulate air, cool attics, and minimize overall air conditioner strain, preventing heat and moisture buildup and lowering energy expenses. There is no need for a damper because downblast ventilators discharge air downward and keep rain out. Dirty or contaminated exhaust is directed away from the roof or wall surface by upblast ventilators. Gravity ventilators use the pressure provided by powered fans in an HVAC system to quietly move air. Wind-driven turbine ventilators do not require electricity to operate; instead, they use wind power to create a vacuum that exhausts air. Industrial and commercial structures, such as warehouses, manufacturing facilities, foundries and laboratories can benefit from exhaust ventilators.