Granny Flat Site Plan NZ: 2026 Exemption & PIM

A granny flat site plan in New Zealand shows how a proposed small standalone dwelling will fit on an existing residential property. It identifies the legal boundaries, existing house, proposed granny flat, setbacks, building coverage, vehicle access, easements, natural hazards and connections for water, wastewater, stormwater and electricity.

Since 15 January 2026, qualifying granny flats of up to 70 square metres can be built without a building consent. However, the exemption has strict design, location, construction, professional and documentation requirements. Homeowners must also obtain a Project Information Memorandum, commonly called a PIM, before building work begins.^[1]

What Changed for Granny Flats in 2026?

The Building Act now contains a specific exemption for eligible small standalone dwellings. The legal term is a non-consented small stand-alone dwelling, although most homeowners simply call it a granny flat, minor dwelling or secondary dwelling.

The exemption allows qualifying dwellings to be built without applying for a building consent when all prescribed conditions are met. The dwelling must still comply fully with the New Zealand Building Code, and the owner remains legally responsible for ensuring compliance.^[1][2]

The exemption does not remove the need to:

• Apply for and receive a PIM before work begins
• Check whether resource consent is required
• Comply with legal-boundary and building-separation requirements
• Use appropriately licensed building professionals
• Obtain utility-provider approvals
• Address natural hazards
• Comply with easements, covenants, consent notices and bylaws
• Submit final plans, records and certificates after completion
• Pay applicable development contributions

Does Every Granny Flat Qualify for the Exemption?

No. The exemption applies only when every condition is satisfied.

Other exemption conditions cover the floor level, building height, framing, roofing, cladding, water supply, drainage, electricity, gas and sanitary facilities.^[2]

Key Building Design Limits

A qualifying granny flat must have:

• A maximum floor level of 1 metre above the supporting ground
• A maximum height of 4 metres above the floor level
• No mezzanine floor
• Light timber or light steel wall and roof framing
• Lightweight roofing within the prescribed weight limit
• Wall cladding within the prescribed weight limit
• Building Code-compliant water, plumbing and drainage systems
• An independent electricity supply
• An independent gas supply where gas is used

Projects that exceed these limits may still be possible, but they will generally need to follow the normal building-consent pathway.

Building Consent and Resource Consent Are Separate

The 2026 changes created two related but legally separate pathways:

The National Environmental Standards for Detached Minor Residential Units, abbreviated as NES-DMRU, took effect on 15 January 2026. They provide a nationwide permitted-activity pathway for qualifying detached minor residential units in residential, rural, mixed-use and Māori-purpose zones.^[3]

A granny flat can qualify for the building consent exemption but still require resource consent. It can also avoid resource consent while still requiring a building consent. Both requirements must therefore be checked independently.^[4]

National Resource-Consent Standards

Under the NES-DMRU, the standard permitted-activity requirements include:

• One detached minor residential unit per site
• A maximum internal floor area of 70 square metres
• At least 2 metres between the granny flat and the principal dwelling
• A maximum building coverage of 50% in residential zones
• At least 2 metres from front, side and rear boundaries in residential zones
• At least 10 metres from the front boundary and 5 metres from side and rear boundaries in rural zones
• Compliance with the applicable zone standards in mixed-use and Māori-purpose zones

District plans can contain more lenient rules. For example, a district plan might permit a 1-metre planning setback. However, a granny flat only 1 metre from a legal boundary would still fail the separate 2-metre condition for the building consent exemption. A building consent would therefore be required even where resource consent is not.^[4]

A PIM Is Still Mandatory

A Project Information Memorandum is required before any work begins under the granny flat building consent exemption.

The homeowner must apply to the territorial authority responsible for the property and include:

• Preliminary design plans
• A description of the proposed building work
• The prescribed application form
• Any additional information requested by the council
• The applicable PIM fee

A complete PIM must generally be issued within 10 working days. When information is missing, the council can request it and pause the processing timeframe until it is supplied.^[2]

A PIM is information—not approval

The council does not approve the granny flat through the PIM process. Instead, it provides site-specific information that can affect the feasibility, design or location of the project.

The PIM and accompanying information may identify:

• Whether the preliminary proposal appears to meet the basic exemption characteristics
• Known natural hazards
• Stormwater and wastewater infrastructure
• Network utility providers and connection requirements
• Relevant council bylaws
• Heritage information
• Regional or district-plan information
• Potential development contributions

Responsibility for deciding whether the project ultimately complies remains with the homeowner and the licensed professionals involved.^[2]

Why the Site Plan Is Important for the PIM

The PIM application includes preliminary design plans. A clear site plan gives the council enough information to understand where the proposed dwelling will sit and what site-specific matters may affect it.

A well-prepared plan helps identify:

• Whether the proposed unit is genuinely standalone
• Whether the 70m² maximum is being respected
• Whether the required boundary and building separations can be achieved
• Whether the site may be affected by flooding, erosion, slippage or another natural hazard
• Whether water, wastewater and stormwater services are available
• Whether easements or consent notices restrict the proposed location
• Whether a new vehicle crossing or access approval may be required

For a broader overview of the information commonly placed on New Zealand drawings, read Everything You Need to Know About Site Plans in New Zealand.

What Should the Granny Flat Site Plan Show?

1. Legal Boundaries and Setbacks

The site plan should show the complete legal boundary and dimension the shortest distance from the proposed external walls to each boundary.

For the building consent exemption, the distance is measured from the legal boundary to the exterior face of the granny flat wall cladding. It is not measured to the foundation centreline, eaves or a nearby fence.^[2]

Show:

• The front legal boundary
• The rear legal boundary
• Both side legal boundaries
• The length of every boundary
• The proposed wall-to-boundary distances
• Any building line, yard or other planning setback

Do not rely on fences

A fence, hedge, retaining wall, driveway edge or line of planting may not follow the legal boundary. MBIE specifically recommends locating boundary pegs rather than relying on a fence when checking the 2-metre separation.^[2]

A licensed cadastral surveyor may be needed where:

• Boundary pegs cannot be found
• The granny flat will be close to the minimum distance
• The site is irregularly shaped
• Existing plans conflict
• A neighbour disputes the boundary
• An easement location must be confirmed

2. Separation From the Existing House

The granny flat must be at least 2 metres from every other residential building to use the building consent exemption.

The site plan should dimension the shortest distance between the external walls of:

• The proposed granny flat
• The existing main house
• Any existing sleepout or minor dwelling
• Any other residential building on the property

Garages, sheds and other non-residential accessory structures should also be shown because they can affect construction access, fire design, servicing and the overall site layout.

3. Floor Area and Building Height

Label the granny flat’s internal floor area directly on the plan. The 70-square-metre limit is measured to the internal face of the exterior walls.

The site plan or accompanying elevations should also identify:

• The finished floor level
• The lowest ground level within the footprint
• The maximum building height
• Any deck, steps or landing
• Whether an internal-access garage is included

An attached or internally accessed garage forms part of the 70m² maximum. A separate detached garage follows its own building and planning requirements.^[2][4]

4. Building Coverage

Building coverage is generally the proportion of the site occupied by counted building footprints.

For residential zones, the national resource-consent pathway uses a maximum building coverage of 50%. More lenient district-plan standards may apply, while other zones use their own coverage requirements.^[4]

A coverage calculation may need to include:

• The existing main house
• The proposed granny flat
• Garages and carports
• Existing minor dwellings
• Covered decks or patios where counted
• Other roofed structures included by the applicable planning definition

Do not calculate coverage using only the proposed granny flat. The complete developed property must be assessed.

5. Water Supply

The granny flat must have a safe and reliable water supply that complies with the Building Code and applicable council rules.

Where an approved network utility system is available and has capacity, the dwelling must connect to it. When a network connection is unavailable, a compliant onsite system may be used.^[2]

The site plan should show:

• The existing water main or approved onsite source
• The existing meter or proposed new meter
• The proposed supply route
• The connection point
• Water tanks, pumps or treatment systems where applicable
• Separation from wastewater and other services

6. Wastewater and Sanitary Drainage

Wastewater should connect to the relevant network utility operator where a suitable system is available. If the network is unavailable or lacks capacity, a compliant onsite wastewater system may be considered.

Show:

• The proposed foul-water drain route
• The connection to the public wastewater network
• Existing inspection points or manholes
• The septic tank and disposal field where applicable
• Drain direction and key levels where available
• Any easement protecting the wastewater system

An onsite system or a change to an existing septic system may require separate regional or district approvals even when the building work qualifies for the building consent exemption.

7. Stormwater

The site plan should explain where water from the granny flat roof and surrounding ground will go.

Relevant information can include:

• Roof downpipes
• Stormwater drains
• Approved network connection points
• Soak pits or onsite disposal systems
• Rainwater tanks
• Existing swales
• Overland flow paths
• Drainage easements
• Surface-flow arrows

Stormwater and wastewater bylaws can affect the location and design of the dwelling. The PIM should provide information about known systems and relevant authorisations.^[2]

8. Electricity and Gas

A granny flat using the exemption must have an independent source of electricity. If gas is used, it must also have an independent gas supply.

The site plan may show:

• The existing switchboard or supply point
• The proposed underground or overhead route
• A new meter or distribution board
• Transformer or service-box locations
• Overhead electricity lines
• Gas cylinders, meters or supply lines

Electricity and gas work must be carried out by properly authorised tradespeople, with the required safety certificates supplied after completion.

9. Vehicle and Pedestrian Access

The site plan should show how residents, emergency services, contractors and utility providers will reach the granny flat.

Include:

• The existing driveway
• Any proposed driveway extension
• Pedestrian paths
• Steps and ramps
• Gates and usable widths
• Parking spaces where provided
• Access to utility meters and wastewater systems

A new or altered vehicle crossing can require separate council or road-controlling-authority approval.^[2]

10. Easements, Covenants and Consent Notices

A granny flat can satisfy ordinary setbacks and still be prohibited from a particular part of the property.

The site plan should show known:

• Utility easements
• Drainage easements
• Rights of way
• Access easements
• Building-line restrictions
• Consent notices
• Land covenants

An exemption under the Building Act or NES-DMRU does not cancel private title restrictions or other legislation. Covenants, consent notices and network-provider requirements may continue to control where the granny flat can be placed.^[4]

11. Natural Hazards

The PIM provides important information about hazards known to the council.

Natural hazards under the Building Act include:

• Erosion
• Falling debris
• Subsidence
• Flooding and inundation
• Overland flow
• Storm surge and tidal effects
• Ponding
• Slippage

When the site is affected by a hazard, the design must make adequate provision to protect the land, the building work and other property. If adequate protection cannot be provided, the building consent exemption cannot be used and a building consent will be required.^[2]

A more detailed site plan may need to show:

• Contours or spot levels
• Flood or overland-flow boundaries
• Minimum floor levels
• Slopes and retaining walls
• Watercourses and drainage channels
• Proposed earthworks
• Hazard-mitigation measures

Licensed Professionals Are Still Required

Removing the building-consent application does not remove the requirement for professional design and construction.

Restricted building work must be designed, completed or supervised by appropriately licensed professionals. This can include:

• A Licensed Building Practitioner with the appropriate design licence
• Licensed carpenters and other building practitioners
• Registered plumbers
• Registered drainlayers
• Licensed electricians
• Gasfitters where gas is installed
• Engineers or other specialists where site conditions require them

Councils do not carry out normal building-consent inspections for granny flats built under the exemption. The homeowner and licensed professionals must therefore maintain strong quality-control records and ensure that the work follows the approved final design.^[2]

The Two-Year Completion Deadline

The granny flat must be completed within two years from the date the PIM is issued.

If the work will not be completed in time, the homeowner must apply for an extension before the deadline. Otherwise, the PIM lapses and the exemption can no longer be relied upon without further action.^[2]

Documents Required After Completion

Once construction is complete, the homeowner must collect the required documentation and submit it to the council that issued the PIM.

The records can include:

• Final architectural plans showing what was actually built
• Final sanitary-plumbing plans
• Final drainlaying plans
• Certificates of Work from designers
• Records of Work from Licensed Building Practitioners
• Plumbing and drainlaying records
• Electrical certificates of compliance and safety certificates
• Gas certificates where applicable

The final plans must reflect any changes made during construction. They must be submitted within 20 working days after the dwelling is complete and all required records have been received.^[2]

Common Granny Flat Site Plan Mistakes

Using a 1-metre boundary setback

A local planning rule may sometimes allow 1 metre, but the 2026 building consent exemption still requires at least 2 metres from every legal boundary.

Measuring from a fence

Fences do not necessarily follow the legal boundary. Use verified title, survey or boundary-peg information.

Failing to show the main-house separation

The granny flat must be at least 2 metres from every other residential building to use the exemption.

Calculating only the granny flat coverage

Building coverage should include all buildings and structures counted under the applicable planning definition.

Treating the PIM as council approval

The PIM provides information. It does not certify that the project complies with the exemption, Building Code or resource-management requirements.

Starting work before the PIM is issued

The exemption requires the homeowner to apply for and receive the PIM before building work begins.

Leaving services off the drawing

Water, wastewater, stormwater, electricity and gas connections can determine whether a proposed location is practical.

Building across an easement

A location can meet the normal boundary setbacks while still interfering with protected infrastructure or access rights.

Ignoring natural hazards

Flooding, overland flow, erosion, subsidence or slippage can require design changes, specialist input or a building consent.

Assuming building and resource consent exemptions are identical

They are separate legal pathways. The project must be checked against both.

Using an unscaled aerial image

An aerial photograph alone normally cannot clearly prove boundaries, dimensions, setbacks, coverage and service routes.

Information to Gather Before Ordering a Site Plan

• Property address
• Record of title
• Lot and deposited-plan information
• Existing survey, if available
• Boundary dimensions
• Location and dimensions of the existing house
• Proposed granny flat floor plan and outside dimensions
• Proposed building height and floor level
• Distances to boundaries and the existing house
• Existing garages, sheds, decks and other structures
• Driveway, parking and pedestrian-access information
• Known easements, covenants and consent notices
• Water, wastewater, stormwater and power information
• Existing site levels, contours or hazard information
• Photographs of the property
• Any council, designer or utility-provider correspondence

Order a Granny Flat Site Plan in New Zealand

NZ Site Plan can prepare a clear, easy-to-read drawing showing your legal property layout, existing house, proposed granny flat, setbacks, building separation, access, known easements and proposed service connections.

The plan can be prepared using an existing survey, title information, council mapping, project measurements, photographs and preliminary architectural plans supplied by the homeowner or designer.

Where the project requires cadastral surveying, geotechnical advice, structural engineering, drainage design, onsite wastewater design, resource-consent planning or other licensed professional services, those documents must be obtained separately.

Frequently Asked Questions

Can I build a granny flat without building consent in 2026?

Yes, when the proposed dwelling meets every condition in Schedule 1A of the Building Act. It must be new, standalone, single storey, no larger than 70 square metres and compliant with the location, design, professional and documentation requirements.

Do I still need a PIM?

Yes. A PIM must be issued before any building work begins under the exemption.

Is a PIM the same as building consent?

No. A PIM provides information about the property, hazards, services, bylaws and other requirements. It does not approve the building work.

How close can an exempt granny flat be to a boundary?

The external walls must be at least 2 metres from every legal boundary to use the building consent exemption.

How close can it be to the main house?

It must be at least 2 metres from the main house and every other residential building.

Can a local council allow a smaller setback?

A district plan may have a more lenient resource-management setback. However, the separate building consent exemption still requires a minimum 2-metre distance from legal boundaries and residential buildings.

Does the granny flat need resource consent?

Not when the project meets the NES-DMRU permitted-activity standards or a more lenient applicable district-plan rule. Other matters such as earthworks, hazards, wastewater or protected infrastructure can still require consent.

Can I convert an existing garage?

A conversion may qualify under the NES-DMRU planning pathway, but it does not qualify for the building consent exemption because that exemption applies only to wholly new dwellings. A building consent will normally be required.

Can the granny flat include a garage?

Yes, but an attached or internally accessed garage is included within the 70-square-metre maximum.

Can I use septic wastewater disposal?

Potentially. An onsite system may be used where a suitable network connection is unavailable, but it must comply with the applicable technical requirements and may need separate council or regional approval.

Does council inspect an exempt granny flat?

Councils do not conduct the normal building-consent inspections. The homeowner and licensed building professionals are responsible for compliance, quality control and maintaining the required records.

How long do I have to finish construction?

The work must be completed within two years of the PIM issue date unless the council grants an extension.

Do final plans still go to council?

Yes. Final plans, Records of Work, Certificates of Work and applicable electrical and gas certificates must be submitted after completion.

Do I need a boundary survey?

A new survey is not automatically required for every project, but it may be necessary when legal boundaries or easements cannot be established accurately from reliable existing information.