9.19.1.2.(2)

Intent 1:

To limit the probability of an inadequate vent area for roofs, which could lead to:

• condensation,
• the accumulation of moisture, or
• the formation of ice dams.

This is to limit the probability of deterioration, which could lead to compromised structural integrity of attic or roof assemblies or of elements protected by attic or roof assemblies, which could lead to harm to persons.

Intent 2:

To supersede the requirement stated in Sentence 9.19.1.2.(1), where the air pressure differential from eave to ridge is limited or where the space below the sheathing is interrupted by framing.