New Granny Flat Regulations in NZ: What Builders Need to Know About H1 Report Compliance

Big changes are coming for granny flats in New Zealand.

From early 2026, small standalone dwellings up to 70 m² may be built without a building consent, provided they meet certain conditions. This “consent-free” option is designed to make it easier for homeowners to add a small secondary dwelling, but it does not remove the need for compliance with the NZ Building Code, particularly H1 Energy Efficiency requirements.

For builders, designers, and homeowners, understanding these rules is crucial to delivering comfortable, energy-efficient, and compliant granny flats.

What the new consent-free rules allow

The new regulations mean that many small standalone dwellings can bypass the traditional building consent process if they meet the following criteria:

• Size limit: Maximum of 70 m².

• Design simplicity: Single-storey, straightforward layout.

• Professional build: Must be designed and built by licensed builders, plumbers, and electricians.

• Council notification: Homeowners must notify their council before and after construction.

This new pathway reduces delays and consent costs, making it easier for homeowners to add a granny flat or tiny home on their property.

Why H1 compliance still matters

Even with consent-free building, H1 Energy Efficiency standards remain mandatory. H1 sets out minimum thermal performance requirements for walls, roofs, floors, windows, and ventilation systems. Compliance ensures:

• Comfort: The dwelling stays warm in winter and cool in summer.

• Energy efficiency: Reduced heating and cooling costs.

• Building quality: Meets NZ Building Code standards for resale and insurance purposes.

Key H1 considerations for granny flats include:

• Insulation: Correct R-values for walls, floors, and roofs according to location.

• Glazing performance: Windows and skylights must meet required U-values and solar gain standards.

• Overheating: Ensure the dwelling stays cool in summer by using shading, orientation, and ventilation strategies to prevent excessive heat gain.

Builders cannot skip these requirements; even consent-free builds must meet all H1 standards.

How we can help - H1 Reports for all building sizes

Navigating H1 compliance can feel complicated, especially with the new consent-free rules. That’s where our H1 report service comes in. We provide council-ready H1 reports for granny flats and small dwellings, ensuring your build meets all energy efficiency requirements, even if a full building consent isn’t needed.

Our service includes:

• Accurate thermal calculations for walls, floors, roofs, and glazing, helping you avoid over-specifying insulation or expensive glazing.

• Professional, council-ready H1 reports for compliance and documentation, reducing the risk of costly redesigns or RFIs.

• Practical advice on design improvements that enhance energy efficiency and comfort while keeping material and construction costs down.

• Quick turnaround to keep your project on schedule, saving both time and money.

By using our H1 reports, builders, designers, and homeowners can save time, reduce risk, and deliver energy-efficient, compliant granny flats that meet the NZ Building Code standards.

Key takeaways

• Consent-free does not mean standard-free – H1 still applies.

• Proper planning and professional H1 reporting ensure comfort, compliance, and energy efficiency.

• Using our H1 report service simplifies the process, giving you peace of mind and supporting smooth council notification.

Want to make your granny flat project stress-free and fully compliant? Contact us today for a professional H1 report tailored to your design.