Design a granny flat: step-by-step guide
Last updated: 3 July 2026
This guide provides step-by-step instructions and process stages for designing granny flats built using the building consent exemption. It clarifies roles and responsibilities for key parties and explains important steps and considerations.
Step 1: Project information memorandum (PIM) application is lodged
The homeowner checks the council website to confirm how they can apply for a granny flat PIM, what information is needed to support the application and what the fee is.
They complete an application through the council online portal, providing the required information and pay the PIM fee.
Form 2AA: PIM application [PDF 207KB]
Step 2: PIM application received
The council receives the PIM application for a granny flat.
Step 3: council (territorial authority) checks PIM application
The council lodges the PIM application in their system and checks that all the required information has been provided.
They queue the application for processing and start the 10-working day processing clock.
Step 4: council processes the PIM
The council reviews the PIM application and supporting information to check that the proposed granny flat is new, standalone, 70 square metres or less and single storey.
They check:
- requirements of the Resource Management Act (RMA) (local and regional plans)
- their local bylaws, and
- that the land is not likely to be affected by one or more natural hazards.
The information checked includes:
- special features of the land
- details of what existing stormwater or wastewater utility systems are present on the proposed building site and what authorisations are needed to connect to them.
The council assesses the granny flat as a permitted activity under the RMA.
Step 5: council issues the PIM
The council issues the from 2AAB PIM and form 2AAC PIM additional information within 10 working days of formally accepting the application.
The council issues the 3A development contributions (DC) notice. This confirms the amount of DCs that are payable for the project and that these are due within 20 working days of the granny flat being completed.
The council property record is updated to note:
- the issue of the PIM
- record the assessment of the proposal, and
- that the granny flat must be complete within two years of the date that they issued the PIM.
Form 2AAC: PIM additional information [PDF 222KB]
Form 3A: Development contributions (DC) notice [PDF 129KB]
Step 6: project timeframes are understood
The homeowner receives the PIM and additional information. They understand that the project must be complete within two years of the date of issue of the PIM. They plan their project to complete the work within this timeframe.
Step 7: designer reviews the PIM
The homeowner provides the PIM to the designer who reviews it. The designer notes that the location of the council sewer is different to what is shown on their preliminary plans. The designer discusses this with the homeowner and they agree to amend the plans to reflect the information provided in the PIM.
Step 8: Certificate of Work is completed
The designer develops full construction plans and specifications based on the preliminary plans and the information provided in form 2AAB PIM and form 2AAC PIM additional information.
They check MBIE guidance about the granny flats exemption conditions for building design, and ensure that the granny flat complies fully with these and the Building Code.
The designer uses the building design conditions checklist to confirm this. They complete a Certificate of Work (CoW) and provide it along with the plans and specifications to the homeowner.
- Completion checklist [PDF 316KB]
- Completion checklist [PDF 326KB, simplified Chinese]: 祖母房豁免：竣工清单
- Form 2A: record of design work Licensed Building Practitioner [PDF 204KB]
Used by Licensed Building Practitioner (LBP) designers to record any restricted design work they complete on a granny flat.
Step 9: quotes for building work obtained
The homeowner chooses a project management approach and visits the Licensed Building Practitioner (LBP) website to find an LBP builder to build the granny flat.
They meet with builder who is appropriately qualified, experienced in residential construction, and familiar with the Building Code and granny flats exemption conditions.
They discuss the project and the homeowner obtains quotes for the building work.
Search the LBP register for a builder – lbp.govt.nz
Step 10: consumer protection measures understood
The homeowner checks what consumer protection measures are available. They understand that the work will require a disclosure statement and standard checklist and formal contract as the value of building work is greater than $30,000.
Step 11: LBP builder selected
The homeowner selects an LBP builder and agrees:
- the price for the project, and
- when payments will be made.
The builder provides a completed disclosure statement and standard checklist.
The homeowner and their lawyer ensure that the builder has adequate insurance policies in place and discuss what warranties the builder offers in relation to the building work.
Find out about disclosure statements and standard checklists
Step 12: written contract is signed
The homeowner asks their lawyer to prepare a written contract for the work. The homeowner and builder sign the contract.
Step 13: construction insurance and finance arranged
The homeowner:
- arranges construction insurance and finance, and
- gives the finance provider the information needed to confirm the building work will comply with the exemption conditions and the Building Code.
Step 14: site/project manager appointed
The homeowner uses the due dilligence checklist to help understand their responsibilities and the process so that they know what they need to do.
They appoint a site manager with the right qualifications and experience to project manage the build and ensure that it goes smoothly.
- Due diligence checklist [PDF 357KB]
Check you have covered the key steps for a granny flat project under the exemption. - Due diligence checklist [PDF 358KB, simplified Chinese]: 祖母房豁免：业主尽职调查清单
Step 15: council approvals are obtained
The homeowner obtains necessary approvals from the council for associated works, for example connections to network utility operator (NUO) services.