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Wet area

A wet area is any room or zone in a residential building that requires a waterproofing system under AS 3740:2021 and NCC 2022 Part 10.2.

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A wet area is any room or zone in a residential building that requires a waterproofing system because water or moisture is regularly present. Under NCC 2022 Housing Provisions Part 10.2.1 and AS 3740:2021, wet areas include shower areas, bath and spa areas, laundries, toilets, kitchen and bar areas with inset vessels, and rooms containing washing machines.

AS 3740:2021 classifies wet areas into three categories based on risk: Category 1 (high, includes all shower zones), Category 2 (moderate, bathroom floor outside the shower), and Category 3 (low, wet areas without a shower). The category determines the waterproofing requirements applied.

Also known as: wet zone.

Category: Wet areas.

See also


Last updated: 2026-05-08. Verified: 2026-05-08. Quarterly review for currency.