Non-consented Granny Flats
Could Your Project Qualify? Key Eligibility Conditions
To qualify for the exemption, your granny flat must meet all the following conditions. If not, you'll need a standard building consent.
- Be new, standalone (detached), single-storey (no mezzanine), and self-contained. It must function as a complete dwelling (classified as ‘Housing – detached dwelling’ under the Building Code), intended for a single household or family.
- Have a floor area of 70 square metres or less (internal dimensions).
- Have a maximum floor level of 1 metre above the supporting ground and a maximum building height of 4 metres above the floor level.
- Be at least 2 metres from other residential buildings or legal boundaries and not built across allotment boundaries.
- Use lightweight materials:
- Roof cladding max 20kg/m².
- Wall cladding max 220kg/m².
- Light steel or timber framing.
- Connect to utilities (water, surface water, foul water) via network utility operators (e.g., council systems) where available, or use approved on-site systems if unavailable. Systems must follow specific compliance pathways (e.g., G12/AS1 for water supply, E1/AS1 for surface water).
- Meet additional plumbing criteria: Total fixture units ≤30, no pumped systems inside, specific drain sizes/grades, independent electricity/gas supplies, and no uncontrolled water heating. Showers must be prefabricated units (no level-entry/wet-floor showers).
Your First Tool: Use the official [Building Design Conditions Checklist] to confirm your project's eligibility.
What Grey District Council Does & Doesn't Do
It's important to understand our role in this exemption process.
We DO... | We DO NOT... |
|---|---|
Issue your Project Information Memorandum (PIM) and provide advice on hazards, infrastructure, and planning rules. | Approve or refuse your project under the exemption. |
Receive, file, and store your final documentation on your property file. | Inspect the building work during construction. |
Update future Land Information Memorandums (LIMs) with your submitted records. | Issue a Code Compliance Certificate. |
Enforce the Building Act if work is non-compliant or dangerous. | Determine if your finished build complies with the Code. |
The Homeowner's Step-by-Step Process
You are legally responsible for compliance. Engage licensed professionals early and do your due diligence.
Key Tools for Your Project:
- For Planning: [Homeowner Due Diligence Checklist]
- For Design: [Building Design Conditions Checklist]
- For Completion: [Completion Checklist]
1. Plan Your Granny Flat & Get Your PIM
The first official step is applying for a Project Information Memorandum (PIM). You must have this before any work starts.
- Check site suitability: Contact our planning team to discuss natural hazards and District Plan rules. A resource consent may still be needed.
- Engage a licensed designer: You'll need a Licensed Building Practitioner (LBP designer), registered architect, or Chartered Professional Engineer to prepare the preliminary plans for your PIM application.
- Submit your PIM application to Grey District Council using Form 2AA. We'll issue it within 10 working days, highlighting any hazards, infrastructure details, and our view on whether your design is likely to meet the exemption.
- Discuss finance and insurance early: Lenders and insurers will likely need proof of compliance. The PIM and final documentation are key for this.
2. Design Your Granny Flat
- Finalise plans with your professional: Ensure full Building Code compliance—no waivers are allowed. Plans must include details for plumbing, drainage, and any required hazard mitigations.
- Receive your PIM before starting work. Review the additional information provided with it carefully with your designer.
3. Build Your Granny Flat
- Start only after receiving the PIM. All restricted building work must be done or supervised by licensed professionals (LBPs for construction, registered trades for plumbing, gas, and electrical).
- Build strictly to the approved plans. Consider hiring a project manager for coordination.
- Arrange quality assurance (QA): Independent inspections at key stages (foundations, framing, pre-line, final) are highly recommended to ensure compliance.
- Manage changes carefully: Any variations must be reviewed by your designer to ensure they don't void the exemption.
- Complete work within 2 years of the PIM issue date. Apply to council for an extension well before this deadline if needed.
4. Complete Your Granny Flat
- Collect all documentation: This includes final 'as-built' plans, Certificates of Work (CoW) from designers, Records of Work (RoW) from all LBPs and tradespeople, and electrical/gas safety certificates.
- Notify Grey District Council: Submit all required records to us within 20 working days of completion.
- Pay any development contributions (outlined in your PIM).
- Keep your own copies for insurance, resale, or future alterations. The records we store will be included in future LIMs.
Critical Responsibilities, Risks & Tips
- Your Legal Role: As the homeowner, you are accountable under the Building Act for ensuring compliance. Non-compliance can lead to fines, prosecution, a Notice to Fix, and future issues with insurance or selling your property.
- Quality is Your Responsibility: We do not inspect exempt work. Using licensed professionals and considering independent QA is your best path to a safe, compliant outcome.
- Understand the Costs: Expect a PIM application fee and potential development contributions. For work over $30,000 (incl. GST), a written contract is mandatory, which provides a 12-month defect repair period and 10-year implied warranties.
- Resource Consent is Separate: This building consent exemption does not override District Plan rules. Always check if you need a resource consent.
- Top Tips: Start early, keep thorough records, and consult professionals every step of the way. If your project is delayed, apply for a PIM extension before the 2-year anniversary.
For More Information & Resources
Grey District Council Building Team: For site-specific advice and PIM applications.
- Email: building@greydc.govt.nz
- Phone: 03 769 8600
MBIE (Ministry of Business, Innovation & Employment): For all official guidance, checklists, and forms.
- Website:building.govt.nz/grannyflats
We're here to help make your project smooth and compliant!