As you are probably aware, condensation occurs when moisture-laden air meets a cold surface. It has become a concern in recent times, particularly in the colder parts of Australia, and NCC 2019 Building Code of Australia now includes a section on Condensation Management (Part F6), although directed to Class 2 and Class 4 buildings. AS 1684 does not address cavity issues since the Standard deals with all types of timber frames including those with no cavity (cladding on the external face, lining on the internal face). It's not possible to deal with condensation management in detail here, but the Australian Building Codes Board (ABCB) has published a useful handbook available for download via this link https://www.abcb.gov.au/Resources/Publications/Education-Training/Condensation-in-Buildings.Condensation
Answered on 01-03-2021
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