Small stand alone dwellings (granny flats)

Last updated: 15 Jan, 2026 01:56pm

Recent legislative change has allowed the construction of small standalone dwellings to be undertaken without the need to apply for a building consent. These are typically referred to as granny flats.

Before starting any work, it is important to check that your project meets all the exemption criteria under the Building Act and NES-DMRU (National Environmental Standards for Detached Minor Residential Units) and any rules under the Proposed Wairarapa Combined District Plan (Decisions Version). In Carterton, the NES-DMRU applies in the Māori Purpose Zone, Mixed Use Zone, General Residential Zone and General Rural Zone. The NES-DMRU sets limits for building coverage and setbacks. The rules and standards of the District Plan continue to apply in relation to natural hazards, reverse sensitivity, subdivision, infrastructure etc. 

Here is a link to the National Environmental Standard for Detached Minor Residential Units – https://www.legislation.govt.nz/regulation/public/2025/0315/latest/LMS1556192.html#LMS1556232 

Before you start to build a standalone dwelling (granny flat) you should check to make sure you meet all of the very specific requirements. If so;

  • You will need to get some basic plans. Note that the plans will need to be properly drawn to a recognised scale etc.
  • Submit an application for a project information memorandum. This involves completing the prescribed application form and submitting that to Council (note; fees apply).

There are a broad range of requirements that must be met in order to be able to undertake the work. Ultimately the owner is responsible to make the decision around whether the exemption applies or not.

If you buy a prebuilt granny flat, that was built before you had the chance to apply for a PIM, then you must follow the normal building consent process.

Once an application has been made, Council will process the PIM and return it to you with any information we consider applies.

Once you have the PIM you should read it carefully to make sure there are no specific issues raised. If there are no issues you can then start work. The work must be completed within two years (or any further agreed period).

Once you have completed the work you must notify Council that the work has been completed and provide all relevant information.

Council will not check the plans submitted for Building Code compliance, we will not undertake inspections during the work and do not issue any certification on completion of the work. Council are simply a record keeper.

Council are not in a position to provide building or design advice.

As you are required to have a licensed building practitioner involved, they are best placed to assist you with your decision making – not council.

The Ministry of Business Innovation and Employment have provided the following guidance that you may find useful:
https://www.building.govt.nz/projects-and-consents/planning-a-successful-build/scope-and-design/check-if-you-need-consents/building-work-that-doesnt-need-a-building-consent/granny-flats-exemption-guidance-and-resources

Download : Step-by-step guides: Plan, design, build and complete a granny flat

Alternatively you can contact consentsystem@mbie.govt.nz

We suggest you ensure that you have the necessary contracts in place and discuss you project with both your insurer, and if you are funding the project with a loan, your money lender.