From November 2026, the prescriptive H1 Schedule Method for demonstrating energy efficiency compliance will no longer be available for new building consents in New Zealand. If you are planning a new home or a major renovation in Northland, this change affects how your designer and builder prove that the building meets insulation and energy performance requirements under the Building Code.
What is the H1 Schedule Method?
Clause H1 of the New Zealand Building Code sets the minimum energy efficiency requirements for buildings. Until now, the most common way to demonstrate compliance for residential projects has been the Schedule Method. This approach applied fixed minimum R-values to individual building elements such as walls, roofs and floors, regardless of the building's orientation, glazing design or local conditions beyond the broad climate zone.
While simple to apply, the Schedule Method had well-documented limitations. It often led to overly conservative material selections in warmer climates like Northland, limited architectural flexibility, and did not account for how a building actually performs as a complete system. In some cases, highly insulated buildings with large north-facing glazing have experienced overheating because the prescriptive approach did not consider solar gains.
What replaces it?
From November 2026, two compliance pathways remain available under the updated H1/AS1-2 and H1/VM1-2 frameworks:
The Calculation Method
This provides a simplified system-level assessment. It allows flexibility to trade insulation between building elements. For example, a designer could specify less insulation in the walls if the roof insulation is increased to compensate. However, it still largely ignores building context such as orientation and shading.
The Modelling Method
This is the more comprehensive option. It uses detailed simulation of real building behaviour, considering orientation, shading, weather data from NIWA, thermal mass and the full interaction between building elements. For buildings with curtain walls, this is the only available compliance pathway.
The Modelling Method compares the proposed design against a reference building aligned with the old Schedule Method values. If the design responds well to solar orientation and building form, it can outperform the reference case and demonstrate compliance more efficiently.
What this means for Northland builds
Northland sits in Climate Zone 1, the warmest zone in New Zealand. The practical implications of the H1 changes for local projects include:
Reduced over-specification. Under the old Schedule Method, Northland homes sometimes carried more insulation than necessary for the local climate. The new pathways allow designers to right-size insulation based on actual performance rather than blanket minimums.
Better glazing and shading design. Large windows facing north are common in Northland lifestyle homes. The Modelling Method properly accounts for solar gains, which means glazing performance and external shading become active contributors to compliance rather than being ignored.
Thermal bridging accountability. The updated framework places significant emphasis on accounting for thermal bridging in wall constructions. This is where heat transfers through framing members rather than through insulation. Proper detailing at the design stage avoids costly corrections later.
Earlier design integration. Energy efficiency compliance can no longer be addressed as a last-minute consent requirement. The modelling or calculation work needs to happen during concept and developed design stages, not after the drawings are finished.
What to discuss with your builder and designer
If you are planning a new build or substantial renovation in Northland with a consent application after November 2026, these are practical points to raise early:
Ask which compliance pathway your designer intends to use and whether they have experience with the Calculation or Modelling Method. Confirm that energy efficiency modelling is included in the design scope and fee, not treated as an add-on at consent stage. Discuss glazing specifications early, particularly for north-facing windows where solar heat gain coefficients matter. Check that the construction detailing accounts for thermal bridging, especially at window reveals, corners and junctions between different wall systems.
The bottom line
The removal of the H1 Schedule Method is a shift toward performance-based design. For Northland homeowners, it should ultimately mean buildings that are better matched to the local climate, with insulation and glazing choices that reflect how the home actually performs rather than a one-size-fits-all checklist. The key is to ensure your project team addresses energy efficiency early in the design process rather than treating it as a compliance exercise at the end.
This article is general information only. Requirements can differ by site, design and council district plan. Check the current requirements for your own project with the relevant council and qualified professionals.
