Ventilation Maximum 102-12-MB-N Flat Roof Ventilator, 19-3/4 in OAW, 96 sq-in Net Free Ventilating Area, Steel, Black

Unlike the turbine, the maximum ventilators are CSA approved and do not require to rotate to prevent water or snow infiltrations. Its unique storm proof system prevents infiltrations while at the same time capturing the wind flow from all directions and at wind velocities as low as 6 km/hr. With this combination of technology, wind and pressure differentials, a "chimney or, vacuum effect" results in drawing the stale air and moisture out, thus preventing moisture and heat build-up within the attic space. All in one, no need of a wood curb, this model has been designed to allow you to install the roofing membrane onto the base flashing the same way you would a wood curb. We have made an allowance for the membrane so that the neck of the ventilator will go over both the flashing and the membrane.