Minor dwellings — often called granny flats, sleepouts, or secondary dwellings — are becoming increasingly popular across New Zealand. In many cases, you can now build a minor dwelling without a building  or resource consent, provided your design meets key district plan rules around size, height, setbacks, and servicing. However, resource consent is still required if your proposal breaches these standards or your site has infrastructure or planning constraints.

This guide explains what you can build, when you need consent, and what to check before getting started.

What is a minor dwelling?

A minor dwelling is typically a self-contained residential unit located on the same site as a primary home. In New Zealand, minor dwellings are typically limited in size and must meet specific district plan rules relating to floor area, servicing, access, and outdoor space. These rules are designed to enable small-scale additional housing without the complexity of full multi-unit developments.

What’s changed in 2026?

In 2026, Central government streamlined consent pathways for granny flats (minor dwellings) as a permitted activity and without requiring a building consent. This generally means a minor dwelling can be built without resource consent if it meets key performance standards, such as site coverage, height limits, setbacks, and outdoor living space requirements. Building consent may still be needed for some structures, but the approval pathway has become simpler. For homeowners, this reduces uncertainty and speeds up project timelines.  

When Do You Need Resource Consent for a Minor Dwelling?

You will typically need resource consent for a minor dwelling if your proposal does not meet district plan rules.

Common triggers include:

• exceeding the 70m² size limit

• building too close to boundaries (setback infringement)

• breaching height in relation to boundary controls

• insufficient outdoor living space

• limited capacity for wastewater, stormwater, or water supply

• additional access or parking requirements

If your site has constraints — such as flooding, access limitations, or infrastructure capacity — additional approvals may also be required.

These service based constraints remain one of the most common reasons minor dwellings require additional approval.   If you hit one of these triggers, you may still be able to build, but with a consent. We are happy to help guide you through that process.

What Can You Build Without Consent?

For many households, a compliant minor dwelling might look like a 60-70m² standalone unit with one or two bedrooms, positioned behind or beside the main home. Simple design choices, like maintaining adequate outdoor space and avoiding boundary encroachments, can keep the project within permitted standards.

A compliant minor dwelling in New Zealand will typically include:

• Up to 70m² floor area

• One or two bedrooms

• A self-contained kitchen and bathroom

• Located behind or beside the main dwelling

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To be permitted, it must also meet the following standards:

• Size - Minor dwellings must be 70m² or less in floor area.

• Height and setbacks - Buildings are generally permitted up to 11m high (or 12m with a pitched roof), with minimum setbacks of:

o 1.5m from front boundary

o 1m from side and rear boundaries

o plus a 4‑metre + 60° recession plane to manage shading

• Outdoor living space – Each dwelling must have at least 20m² of ground‑level outdoor living space (minimum 3m dimension), or 8m² if provided as a balcony.

• Servicing and access – The site must be able to accommodate additional wastewater, stormwater, and water demand, and in some cases an extra onsite parking space.

While national standards now set consistent rules for building height, setbacks, and outdoor living space in many urban areas, minor dwelling size and eligibility remain controlled by individual district plans.

Common Minor Dwelling Projects

We regularly see clients looking to build minor dwellings for:

• granny flats for extended family or ageing parents

• minor dwellings for rental income

• sleepouts or small standalone units

• second dwellings on existing residential sites

Each of these can have different planning implications, so early advice can help avoid delays.

What to Check Before You Build

While the rules are simpler in 2026, every site still has its own planning context. Before starting, it’s important to check:

• your district plan zoning and rules

• infrastructure capacity (water, wastewater, stormwater)

• site constraints such as flooding or natural hazards

• access and parking requirements

If your project sits close to the limits, getting early advice from a planning consultant or resource consent specialist can help confirm whether consent is required and avoid costly redesigns later.

Not Sure If You Need Resource Consent?

If you're planning a minor dwelling and want clarity on whether you need resource consent, what it will cost, or how long it might take, our team can help.

Inovo’s resource consent planners and planning consultants can quickly review your site and provide clear, practical advice on the best path forward.

Get in touch to discuss your project.

rmplanning@inovo.nz

020 4000 0294  

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Was this article helpful?  Here’s some other topics that might be interesting to you:

‍How does Plan Change 120 affect your development options?

Key Zoning Decisions for Christchurch

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Disclaimer

This article contains general information and opinion based on our expertise. It is provided free of charge and does not constitute legal or other professional advice. The information within it was up to date at the time of publishing.

Have you got further questions about this topic or our other services?

We are always happy to help – drop us an email rmplanning@inovo.nz, or phone us on 020 4000 0294.‍

As Ridgeline moves rapidly from concept to reality, our team at Inovo is proud to support the transformation of this stunning hilltop landscape into one of Christchurch’s most desirable residential enclaves. With road construction now well underway across the Ridgeline site, the next generation of home sites is beginning to take shape against sweeping views of the Port Hills, Christchurch city, and the distant Southern Alps.

Significant earthworks and retaining-wall construction continue to reshape the terrain into build-ready platforms. Stage 5 has now delivered 5,000 m² of retaining walls and 87,000 m³ of earthworks. Stage 6 will add a further 8,000 m² of retaining walls and around 150,000 m³ of earthworks, delivered over four substages.

On the utilities front, and in collaboration with Beca, we are delivering the full water-supply infrastructure: designing a water-supply pump station, rising main, temporary tank farm to service Stage 5, and permanent water reservoirs for Stages 5 and 6. We are also progressing planning and design for the undergrounding of the 66 kV supply, enabling critical infrastructure to be discreetly accommodated beneath the surface while minimising visual and environmental impacts.

As engineering lead, we continue to deliver all associated civil engineering, consenting, erosion and sediment control, and stormwater management, ensuring the development meets stringent environmental and regulatory standards as this new community takes shape.

Inovo has worked on the development of Cashmere Estate since early 2019, when we became lead consultant providing a full range of land development services in resource management planning, surveying, civil engineering and project management for one of the last remaining greenfield hillside areas set aside for development in Christchurch.

Inovo is excited to be partnering with Endura Mining in the planning and delivery of the construction projects for the Snowy River Gold Mine.

As Project Lead, we've hit the ground at pace at Snowy River, leveraging and integrating the expertise and specialist knowledge of the multi-faceted project team.

Snowy River Gold Mine, located on the West Coast of the South Island is New Zealand’s next large-scale underground mining operation – currently employing over 80 people, which will increase to over 200 when the mine is fully operational. The mine’s main ore body, the Birthday Reef, produced 733,000 ounces of gold over 50 years from the early 1900s. The mining operation is being developed to deliver low-cost production of approximately 60,000 ounces per year with a mine life of over 10 years.  

Here at Inovo we are working together with Rawlinsons Limited  to develop important relationships, tools and processes which can be replicated across ongoing work-streams and further projects.