Ridge Vents

Ridge vents, such as continuous or intermittent ridge vents or vented head apron flashings, should always be used in conjunction with intake vents at a lower level.

To prevent creating negative pressures which can draw more moist internal air into the ceiling space, the free surface area of ridge vents should always be less than that of eaves vents.

Saturated water vapour can enter the building when commercial ridge vents are subjected to negative pressures or at times of high humidity associated with mist or fog. Such water vapour can form condensation on the structural framework and appear as a leak. Ridge vents without adequate intake vents can also lead to leakage.

Sarked Roof to Ridge Vent

Sarked roof to ridge.svg