9.20.13.1.(2)

Intent 1:

To limit the probability of a chemical reaction with concrete or mortar, which could lead to the premature failure of aluminum flashing.

This is to limit the probability of precipitation or meltwater ingress, which could lead to:

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

This is to limit the probability of harm to persons.