TL;DR — The short version
From 15 January 2026, a single-storey, self-contained dwelling of up to 70 square metres can be built on an existing residential property in New Zealand without a building consent, provided it meets the Building Code and is built by licensed professionals. For Waikato homeowners, that makes a granny flat a far more practical way to house family, generate income, or add long-term flexibility.
Key takeaways
The 70m² building consent exemption took effect on 15 January 2026. Resource consent for small secondary dwellings was removed at the end of 2025.
Standards have not dropped. Restricted building work must still be done or supervised by a Licensed Building Practitioner, and the council must be notified before and after.
Granny flats serve multiple purposes: family accommodation, rental income, home office, or short-stay letting.
Purpose-built beats off-the-shelf. Design matters for integration, value and longevity.
Reinvesting in your existing property often outperforms moving in today’s Waikato market.
For many homeowners, the idea of a granny flat once felt complicated, expensive, or tied up in red tape.
That’s changed, and this time the change is specific.
What’s changed with the rules
A granny flat, in regulatory terms, is a small self-contained secondary dwelling on an existing residential property. As of 15 January 2026, one of these can be built without a building consent if it meets a clear set of conditions:
It is a single-storey, standalone dwelling of no more than 70 square metres.
It is simple in design and fully complies with the New Zealand Building Code.
All restricted building work is carried out or supervised by licensed building professionals - a Licensed Building Practitioner (LBP), along with licensed plumbers, drainlayers, gasfitters and electrical workers.
You obtain a Project Information Memorandum (PIM) from your council before work begins.
On completion, you provide the council with final plans, Records of Work and certificates of compliance.
Resource consent for small secondary dwellings was removed separately, at the end of 2025. Together, the two changes strip out a significant amount of cost and waiting time.
The intent is straightforward: fewer unnecessary hurdles, without lowering standards. What that creates is genuine opportunity for Waikato homeowners.
More than a family solution
While granny flats have traditionally been associated with accommodating elderly parents or extended family, today’s homeowners are thinking more broadly. A well-designed secondary dwelling can serve several purposes across its lifetime:
accommodation for ageing parents who want independence with proximity
space for adult children returning home or saving for their first property
a dedicated home office, studio, or consulting room
an income-generating rental or short-stay option
The real value lies in flexibility. The ability to adapt your property as your life changes. A 70m² dwelling that houses a parent this decade can be a rental the next.
Purpose-built vs off-the-shelf
There is a growing preference for purpose-built granny flats over transportable, off-the-shelf solutions. And with good reason.
A purpose-designed build allows the new dwelling to be sympathetically integrated with the existing home and site (in scale, materials, and character) so it looks like it was always meant to be there. The goal is a cohesive outcome, not something that feels tacked on.
That’s a meaningful difference, both visually and in terms of how it affects long-term property value. It also lets the layout respond to your actual site: the fall of the land, the sun, the access, the outlook.
Reinvest in what you already own
From an investment perspective, a compliant, well-designed secondary dwelling can significantly improve both the usability and the value of your property. It allows you to reinvest in what you already own, rather than face the costs and disruption of relocating.
That brings the conversation back to a familiar question:
“Relocate… or reinvest?”
For many Waikato homeowners, investing in their existing property delivers a stronger return, particularly when the alternative involves buying into an inflated market or selling in a deflated one.
Compliance still matters
The regulations may be more accommodating, but the standards haven’t dropped. The consent requirement has gone; the Building Code obligation has not. Using an experienced, registered builder ensures the result is:
safe and structurally sound
durable and low-maintenance
correctly documented, with Records of Work filed and certificates of compliance in place
future-proofed against further regulatory change
value-adding rather than value-diluting
It’s worth being clear about where the responsibility now sits. Under the exemption, there is no council inspector signing off each stage, your LBP carries that accountability. Who you choose matters more than it used to, not less.
Done properly, a granny flat isn’t just extra space. It’s a strategic upgrade that adapts your home to modern living while strengthening its future worth.
Final thought
If you’ve been thinking about adding a secondary dwelling - for family, income, or long-term flexibility - the conditions have rarely been better. The key is getting the planning and execution right from the start.
Granny flat FAQs
Can I build a granny flat without a building consent in New Zealand?
From 15 January 2026, yes. A single-storey, standalone dwelling of up to 70 square metres can be built on an existing residential property without a building consent, provided it is simple in design, complies with the Building Code, and the restricted building work is carried out or supervised by licensed building professionals. You still need a Project Information Memorandum from your council before work starts, and you must supply final plans, Records of Work and certificates of compliance once it is finished.
How big can a granny flat be in NZ under the new rules?
Up to 70 square metres. That is the threshold for the building consent exemption. Anything larger, or anything more than a single storey, still requires a full building consent through your local council.
Do I still need a Licensed Building Practitioner?
Yes. The consent requirement has been removed; the standard has not. Restricted building work must still be carried out or supervised by an LBP, with plumbing, drainlaying, gasfitting and electrical work done by the relevant licensed trades. Your LBP completes and submits the Record of Work to the council and confirms the build meets the Building Code.
Do I need resource consent for a granny flat?
For most standard sites, no. The resource consent requirement for small secondary dwellings was removed at the end of 2025. District plan rules can still apply to specific sites, so it is worth confirming your particular property early.
Can I rent out a granny flat in the Waikato?
Yes. A compliant, self-contained secondary dwelling can be used as a long-term rental or a short-stay let, subject to your district plan and your obligations under the Residential Tenancies Act. Many Waikato homeowners use the flexibility to switch between family use and income over time.
Is a purpose-built granny flat better than a transportable one?
A purpose-built dwelling is designed for your specific site, so it can be matched to the existing home in scale, materials and character rather than sitting apart from it. That integration is what protects long-term property value, and it usually delivers a more usable layout for the space available.
How much does a granny flat cost to build in the Waikato?
Cost depends on site access, ground conditions, services connections, and the level of finish you want. The consent exemption removes some council fees and time, but design, materials and trade costs remain the bulk of the budget. The most reliable way to get a number is a site visit and a scoped quote.
Thinking about a granny flat on your property?
We’re happy to talk through what’s possible on your site, what it typically involves, and whether it makes sense for your situation. No pressure, just a practical conversation.
