13A. Ground moisture barrier

Man checking ground moisture barrier

A building consent is not required for the installation of a ground moisture barrier in an existing building.

What the law says

Subject to section 42A of the Building Act, Schedule 1 exempts the following from a building consent:

Building work in connection with the installation in an existing building’s subfloor space of a ground moisture barrier.

Guidance on the exemption

This exemption reflects that the installation of ground moisture barriers is building work with a low risk of causing danger to people or damage to other buildings.

Is your rental compliant?

The Residential Tenancies (Healthy Homes Standards) Regulations 2019, which came into force on 1 July 2019, set minimum requirements for rental properties in relation to heating, insulation, ventilation, moisture ingress and drainage, and draught-stopping.

This includes a requirement that all residential rental premises with enclosed subfloor spaces must have ground moisture barriers installed in those spaces where reasonably practicable.

The regulations provide a transitional period to give landlords time to comply with the new standards:

• 1 July 2021 – From this date, private landlords must ensure that their rental properties comply within 90 days of any new tenancy
• 1 July 2021 – All boarding houses must comply
• 1 July 2023 – All Housing New Zealand and registered Community Housing Provider houses must comply
• 1 July 2024 – All rental homes must comply

Examples where this exemption could apply

The subfloor space within an existing house is being retrofitted with a ground moisture barrier.

Examples where building consent is required

A ground moisture barrier is to be installed within the subfloor space of a new house under construction.

This information is published by the Ministry of Business, Innovation and Employment’s Chief Executive. It is a general guide only and, if used, does not relieve any person of the obligation to consider any matter to which the information relates according to the circumstances of the particular case. Expert advice may be required in specific circumstances. Where this information relates to assisting people: