To limit the probability of the accelerated deterioration of stucco or corrosion of fasteners, metal lath or reinforcing, which could lead to inadequate strength or resistance to freeze-thaw stresses, which could lead to the delamination or cracking of stucco under gravity, wind or impact loads, or freeze-thaw stresses.
Where stucco is applied to masonry chimneys, this is to limit the probability of precipitation or meltwater ingress, which could lead to the premature failure of chimney liners, which could lead to the leakage of carbon monoxide gas into living space, which could lead to the acute poisoning or asphyxiation of persons.