What constitutes a proper ventilation system? Actually the ventilation system for all structure is based on the principle of a wind funnel. A proper roofing ventilation system will consist of an air intake hose and a corresponding exhaust hose to ensure there is proper ventilation of air within and under the roof. The passage of external air around the roof will act like a cooler and ensure the internal temperature will not rise to a temperature greater than that of the air outside. The system is akin to the fireplace we have at homes. The warm air rises and creates a slight suction near the mouth of the intake hose. The relatively cooler air outside the hose removes excess heat from the underside of the sheeting as it exits the exhaust. This cycle of heat exchange regulates the temperatures of the new shingle, saving your investment in roofing from becoming a cinder.