Building a non-consented small stand-alone dwelling (granny flat)
It’s now easier to build a small, stand-alone home (often called a granny flat) in Marlborough.
Central Government introduced national rules from January 15, 2026, which means many properties can add a self-contained home of up to 70 square metres without needing a resource consent or building consent. This only applies if the build meets strict rules.
These changes, called the ‘Granny Flats exemption’, are designed to make it easier for people to add small homes on their property. They came from the National Environmental Standards for Detached Minor Residential Units and the Building and Construction (Small Stand-alone Dwellings) Amendment Act 2025.
What homeowners need to know
You cannot start building straight away. Even though a building consent is not needed, there are still legal steps you must follow:
- Check that your project meets the rules
- Apply to council for a Project Information Memorandum (PIM) and include your plans
- All design and building work must be done, or closely supervised, by licensed building professionals
- After the build is finished, you must send set documents to council within 20 working days
- The build must also be completed within two years of your PIM being issued.
Eligible projects
To use this exemption, the home must:
- be a new, stand-alone building (that is, it is wholly new and not an addition or alteration to existing building work or an existing building)
- it has a floor area that is equal to or less than 70 square metres
- It is a single storey only
- meets the Building Code rules for a detached building
- be built using standard building methods and materials
- sit at least two metres from boundaries and other homes
- be on land not affected by natural hazards such as flooding or slips, unless the risk can be properly managed.
This exemption does not apply to sleepouts, sheds, garages, tiny houses on wheels, existing buildings, or anything larger than 70 square metres.
Use the official Building Design Conditions Checklist to confirm your granny flat’s eligibility.
The Granny Flats Exemption Guidance may also be a helpful resource.
Go to the granny flats exemption guidance and resources page on the Building Performance website
Who can do the work
All design and building work must be carried out or supervised by Licensed Building Practitioners.
Before you build: Apply for a PIM
A PIM gives you information about your land and anything that could affect your build, such as hazards or services.
You must apply for a PIM before any building starts. This step is required by law. A PIM is not an approval – it does not say yes or no to your project.
Your application must include plans and a short description of the build. If your granny flat is built off-site, you only need a PIM for the final location.
Council will note whether your proposal is likely to meet the rules and flag any issues, such as natural hazards. Council will also tell you if you need to pay development contributions.
Council does not inspect or check builds done under this exemption.
Application for PIM for non-consented small standalone dwelling
Development Contributions
Development Contributions help fund the infrastructure needed to support growth, such as water, wastewater, stormwater, roading, footpaths, green spaces and community facilities.
Granny flats are assessed for Development Contributions during the PIM process.
Any Development Contribution must be paid within 20 working days of completing the building work.
Planning rules and resource consent exemptions
You may not need a resource consent if your project fully complies with either:
- the National Environmental Standards for Detached Minor Residential Units (NES-DMRU), or
- the proposed Marlborough Environment Plan (operative in part) rules for your zone.
If your project does not fully comply with either the new NES-DMRU or the District Plan, a Resource Consent is required. Building cannot begin until that consent is granted.
Effluent systems
If an on-site effluent treatment system (septic tank and field) is proposed, the Proposed Marlborough Environment Plan (Operative in Part) rules apply and you will need to contact Council for further information.
What to do once you’ve finished building
Within 20 working days of completing the work, you must provide:
- final plans
- Records of Work from Licensed Building Practitioners
- plumbing, drainage, gas and electrical certifications
These records are added to the property file and appear on future LIMs.
Council does not issue a Code Compliance Certificate under the exemption but does have enforcement powers over unsafe or non-compliant work.
More information
For detailed information, including situations where exemptions do not apply go to the following external links.
You are advised to discuss your plans with Council early in your process to avoid costly redesigns. Please contact either the duty planner dutyplanner@marlborough.govt.nz or the duty builder dutybuilder@marlborough.govt.nz .
