9.20.13.12.(1)

Intent 1:

To limit the probability of water running back under window sills or down the face of masonry, which could lead to water ingress.

This is to limit the probability of:

• the deterioration of masonry due to freeze-thaw stresses, or
• the deterioration of masonry elements, which could lead to compromised structural integrity.

This is to limit the probability of damage to the building.