Sentence 9.3.2.5.(1)

Intent 1:

To limit the probability of the entrapment of moisture inside closed building envelopes, which could lead to:

• excessive post-installation shrinkage and warping,
• wood decay, which could lead to loss of lumber strength, or
• the exposure of other materials that are moisture-sensitive and susceptible to decay to high moisture levels and decay fungi.

Where lumber is used in assemblies that are required to provide fire resistance, this is to limit the probability of the compromised fire resistance of the assembly, which could lead to harm to persons.