To limit the probability that concrete blocks will
be unable to resist expected structural or environmental loads.
This is to limit the probability of:
- where masonry construction is required to provide fire
resistance, excessive deformation or cracking, which could lead to
compromised fire resistance of the assembly, or
- for chimneys and fireplaces, excessive heat transfer,
which could lead to the ignition of combustible building components.
This is to limit the probability of damage to the building.