Streamlining Granny Flat Construction: New Zealand’s Latest Legislation
The Government has introduced significant changes aimed at making it easier for homeowners to build small standalone dwellings, commonly known as “granny flats”. Recent legislative changes remove the need (in situations that fit the requirements of the rules) for building consents and, in many cases, resource consents, while still maintaining essential safety and quality standards.
So what has actually changed, what hasn’t, and what should homeowners be thinking about before they start?
What’s Changing?
Building Consent Exemption: From 15 January 2026, a new building consent exemption applies to small standalone dwellings up to 70 square metres. Provided the relevant requirements of the Building Act 2004 are met, homeowners can now construct a granny flat without obtaining a building consent.
Removing the requirement for a building consent is a meaningful shift, but it does not remove the need for compliance. To rely on the building consent exemption:
- The design must be simple and for a single-storey standalone dwelling which fully complies with the Building Code.
- Construction must be carried out or supervised by a Licensed Building Practitioner.
- A Project Information Memorandum (PIM) must be obtained before construction begins.
- the local council must be notified both before construction begins and once the build is complete. Councils do not inspect or sign off exempt building work. Responsibility for compliance sits squarely with the homeowner and the professionals they engage.
In practical terms, the main benefits are likely to be reduced consenting costs, shorter timeframes, and less administration. However, the technical and compliance obligations remain.
Buildings designed and built under the MultiProof or BuiltReady schemes will automatically comply with some proposed exemption conditions.
Resource Consent Exemption: At the same time, the Resource Management (National Environmental Standards for Detached Minor Residential Units) Regulations 2025 also came into force.
These regulations establish a nationally consistent permitted activity framework, allowing detached granny flats to be built without resource consent, provided the permitted activity standards are met. The regulations apply across residential and rural zones, subject to specific site and environmental constraints.
Considerations for Homeowners
The building consent exemption and the resource consent exemption operate independently. A project may qualify under one regime but not the other, so both must be considered.
Before proceeding with a granny flat project, homeowners should carefully consider the following:
- No Retrospective Application: The exemption does not apply retrospectively. Granny flats built, or where construction has started before the exemption came into force, will still require building consent.
- Future Sales: When a property with a granny flat is later sold, a prudent purchaser would investigate whether the dwelling complies with all legal requirements. Ensuring compliance from the outset helps protect the marketability of the property in the future and is crucial to avoid complications during the sale process.
- Development Contributions: Even where Councils are not involved in a consenting process for a granny flat, they may still levy development contributions through the PIM process. These contributions would reflect increased demand on infrastructure such as water, wastewater and transport networks and should be factored into project budgets early.
- Environmental and Legal Compliance: The new regulations do not override all planning rules. Matters such as natural hazards, site‑specific constraints, infrastructure capacity and other district plan provisions such as heritage overlays, may still restrict development. Early advice can help identify whether a granny flat is permitted on a specific site.
The new granny flat framework represents a significant and practical shift in New Zealand’s housing landscape. While the process has been simplified, it has not been deregulated. Compliance, documentation and professional oversight remain central.
Homeowners considering a granny flat should approach the project with a clear understanding of both the opportunities and the obligations involved.
Have questions about how the new granny flat rules apply to you? Get in touch with our Property team.
Special thanks to Partner Emma Tomblin and Solicitor Jack Mitchell for preparing this article.
Disclaimer: The content of this article is general in nature and not intended as a substitute for specific professional advice on any matter and should not be relied upon for that purpose.
