If you are considering building a granny flat/a small stand alone dwelling for a detached minor residential unit (DMRU) there are four areas to check to see whether you can build one.
Understanding the building requirements of the new small standalone dwelling exemption. Get the details here.
Find out if you need a resource consent or are exempt from a resource consent under the NES-DMRU (planning requirements). Get the details here.
Will you be required to pay any development contributions (DCs)? Get the details here. Page 9 of the policy document will be helpful.
You will need to apply to connect to the Council and other services. Get the details here.
Please note: Due to the terms used by Central Government in their legislation, all the following terms mean the same thing: granny flat, a small stand alone dwelling for a detached minor residential unit & DMRU.
Do I still need resource consent?
It depends on whether the granny flat complies with all of the regulations in the National Environmental Standard for Detached Minor Units or not. Please use the checklist on the granny flat planning page to determine whether or not the NESDMRU is complied with. If you have further questions, check with a Duty Planner.
Do I need to check for natural hazards on my site?
Yes. Before relying on the granny flat exemption, you must check whether your site is affected by natural hazards, such as flooding, coastal inundation or erosion, unstable land (slips), or other hazard overlays in your district plan. Visit our Environmental Map Viewer to get this information,
What happens if my site is affected by a natural hazard?
If a natural hazard applies, the exemption may not be available and a full building consent may be required. A Council Resource Scientist will review applications for natural hazards under sections 71–74 of the Building Act 2004.
Read the MBIE guidance on natural hazards.
Do I need to consider contaminated land (HAIL)?
Yes, you should check whether your site may be affected by contamination, particularly if it has a history such as orchards or horticultural use.
Some properties are listed on the HAIL register. If contamination applies, the exemption may not be available and further approvals may be required.
Enquiries about a specific site can be made to Council’s Duty Planner or Resource Scientist – Contaminants.
Ground conditions and foundation design
Before designing a granny flat, the site must be assessed to determine whether SED foundation design is required (foundation design outside NZS 3604).
This includes consideration of liquefaction, confirmation of good ground, slope instability, proximity to an earthquake fault line, and land disturbance areas (Separation Point Granite LD1 or LD2), which require SED investigation and foundation design.
Can a granny flat be built across two lots or over a legal boundary?
The MBIE Granny Flats Exemption Guidance confirms that a granny flat must not be built across two or more allotments, even if the lots are in the same ownership or on the same record of title. If a proposed granny flat would straddle two lots or cross a legal boundary, the exemption cannot be used and a building consent is required, with any boundary or title matters needing to be addressed through the normal Building Act processes (including section 75 where applicable). This also applies where a waste water field cross onto another lot.
Do I need to check services before designing a granny flat?
Yes. Before paying for design work, you should confirm that your site can support water, wastewater, stormwater, and power connections, and that access and infrastructure capacity will not limit what can be built.
Do I need approval to connect to services?
Any new connection or connection to an existing dwelling needs to have a new (water, wastewater, stormwater and power) service connection application approved by council (Three Waters) or Network Tasman (Electricity) and your power supplier.
This MBIE Granny Flat guidance – home owner due diligence checklist is a useful resource.
Also check out the step by step guides created by MBIE for additional information.
Do I need a PIM?
Yes. A PIM is required before any building work starts if you are using the granny flat exemption.
Is a PIM a building consent?
No. A PIM provides information only. It is not an approval and does not certify building work.
When did the exemption start?
15 January 2026.
Can I draw my own plans?
No. Plans for a granny flat PIM application must be prepared by an appropriately licensed designer. A Licensed Building Practitioner (LBP) responsible for the design must provide a Certificate of Design Work (CoDW) (memorandum of design) with the application.
What do I need to apply?
Preliminary plans (including drainage), confirmation of size and standalone status, proof of ownership, servicing details, planning information, the completed checklist, and a CoDW where restricted building work is involved.
Check out the step by step guides under the "Additional resources" heading on the is page on the MBIE website.
We have put together a helpful checklist to ensure you have provided enough information for the PIM assessment. Read more here.
You can use the Objective Build portal to provide this information to us.
How can I avoid delays with my application?
It is your responsibility to ensure your application is complete and clear.
Council’s self-checklist is a guide only. You must still provide full supporting information for each section. Applications that are missing information or unclear can take longer to process and may lead to requests for more information and extra costs.
Can Council ask for more information?
Yes. Council may request information before accepting your application to confirm it is complete.
How long does it take?
The 10-working-day timeframe starts once a complete application is accepted but may be paused while Council is waiting for requested information that has not been supplied.
Can I start building once I get a PIM?
For a granny flat, you may only start building under the exemption if the PIM confirms the proposal is likely to meet the Schedule 1A exemption criteria and you have any other required approvals such as planning and connection to services permissions in place. If the PIM says the proposal is unlikely to meet the criteria, or it is unclear, you must not start building under the exemption and will be required to apply for a building consent.
What happens if someone starts building and the exemption doesn’t apply?
If building work starts and the granny flat does not meet all the exemption criteria, the work is treated as unauthorised building work. Council may take compliance and enforcement action. This can include requiring work to stop and requiring the owner to resolve the situation, which may include applying for a Certificate of Acceptance (COA) or a building consent, and fixing or removing the work.
What is a fixture unit?
A fixture unit is a standard value used to measure the plumbing load created by fixtures such as toilets, showers and sinks, to help size water and drainage systems correctly, in accordance with G13/AS1 Table 2. Read more on the Building website.
Do I have to consider overhead power lines?
Where the presence of overhead electricity lines is identified, compliance with NZECP 34:2001 is required and applicants should consult Network Tasman Limited.
Do I have to consider underground power cables?
Where underground electricity and other services may be present, applicants are advised to undertake a locate-before-you-dig, process and consult Network Tasman Limited prior to excavation.
Can I use a relocated building?
Yes. The exemption can apply to a newly built relocated small standalone dwelling, provided the proposal meets the exemption criteria (including being standalone, single storey and no more than 70 m²). You must obtain a PIM before work starts, and provide the required completion notification and documentation to Council. Planning and other approvals may still be required.
Does the PIM need to relate to the final site for a relocated building?
Yes. Where a relocated building is proposed, the PIM application must be for the site where the building will be finally located. A PIM is site-specific and cannot be transferred between sites.
What if I change the design during the build?
Work must stop and the change reviewed. If the design has changed to fall outside the exemption criteria, a Certificate of Acceptance may be required for work completed and a building consent for work yet to be started.
What documents must I provide when the build is complete?
You must submit the Completion checklist, Record(s) of Work from Licensed Building Practitioners, as-built construction plans showing what has been built, and any required supporting documentation, and pay any applicable development contributions.
Check out the MBIE Granny Flat exemption completion checklist
How long do I have to complete a granny flat under the exemption?
The granny flat must be fully completed within 2 years of the PIM issue date.
What does completed mean?
This includes completing all building work, notifying Council, providing all required completion documentation, and paying any applicable development contributions.
What if my granny flat will not be finished within 2 years?
The completion date may be extended. If your project will not be completed within the 2-year timeframe, any request to extend the timeframe must be made to Council before the PIM expiry date. Fees apply. If this is not done within the 2-year period, the PIM lapses and the building work may no longer qualify for the exemption.
What if I exceed the 2-year timeframe?
If the granny flat is not completed within the 2-year period, the PIM will lapse and the building work will no longer qualify for the exemption.
Where building work has been completed, a Certificate of Acceptance (COA) will be required for the works carried out.
Where building work has not started, a new PIM will be required before any work can begin.
What are development contributions?
Development contributions are charges Council may require to help pay for the increased demand new development places on infrastructure such as water, wastewater, stormwater, transport, and reserves.
For granny flats, development contributions are still assessed through the PIM process. If payable, Council will issue a development contribution notice with or during the PIM process and payment is required within 20 working days of completion of your granny flat.
Who is responsible for gathering the completion documentation?
The homeowner is responsible for collecting documentation throughout the project and submitting it to Council when the work is complete. Licensed Building Practitioners must provide Records of Work to both the homeowner and the Council that issued the PIM.
Is the building lawful once complete?
Yes. Once all exemption conditions are met, including notifying Council when the work is complete, submitting the required documentation, and paying any applicable development contributions, the building is lawful under the Building Act.
What about future alterations?
They will be treated as alterations to an existing lawful building and may require building consent.
Where can I get help?
Check out the information on this site and at building.govt.nz/grannyflats, or you can contact a Duty Planner or a Duty Building Officer.
