Compare ridge vents vs. power vents.

Based on overall system performance, the ridge vent is a more effective exhaust vent compared to a power fan.

Based on overall system performance, the ridge vent is the most effective. A ridge vent moves air throughout the attic, ventilating the entire underside of the roof sheathing, and therefore the entire attic area. A power vent will only ventilate areas along the path of least resistance from the intake to the power vent. However, a power vent system is generally capable of cooling an attic to a lower temperature during the warm weather. Because it is motor driven, the larger number of air exchanges in an attic delivered by a power vent allow the heat to be removed at a faster rate than a ridge vent, thus cooling more in the general attic area, but not throughout.