Do I need attic ventilation?
To prevent harmful condensation, air must circulate freely under the roof deck. A minimum of 1 ft2 of total net free ventilating area is required for each 150 ft2 of ceiling area, or 1 ft2 for each 300 ft2 of ceiling area if (A) a vapor barrier is installed on the warm side of the ceiling or (B) approximately 1/2 the ventilation is provided near the ridge.
Shingle roof systems which do not have free air circulation under the roof deck (or if they have less venting area than directed above) have reduced coverage under the terms of the PABCO® Limited Shingle Warranty.
See the PABCO® Limited Shingle Warranty for additional details.
See the PABCO® Directions For Application for additional details and related information.