Intent 1:
To limit the probability of:
- water running down the face of masonry and entering
behind primary flashing, or
- the intersection being unable to accommodate differential
vertical movement of chimneys and roof surfaces, which could lead
to the displacement of or damage to flashing.
This is to limit the probability of
precipitation or meltwater ingress, which could lead to:
- damage to masonry or chimney liners from freeze-thaw
stresses, or
- the deterioration of roof systems, masonry walls or
elements protected by such assemblies.
This is to limit the probability of structural failure,
which could lead to of harm to persons.