9.19.1.1. Required Venting

 9.19.1.1. Required Venting 

This Article requires that roof #venting provide a means for allowing #moisture that may have found its way into an #attic or roof space to escape to the exterior. Excess moisture resulting from winter #condensation can raise the moisture level in such spaces to the point where wood can begin to decay. Water leakage into the conditioned space below may also occur when the winter #frost and #ice build-up melts.

Quoted from Illustrated Users' Guide -- NBC2015