Struggling with the new H1 calculation method? Terra Lana provides end-to-end insulation support — from specification through to consent-ready compliance reporting.

Improving the airtightness of the building envelope can improve overall energy performance in modelling tools, and potentially reduce reliance on higher-spec (and higher-cost) insulation by enabling the insulation to perform to its true R-value.

Bring more natural light into your residential designs without compromising thermal performance or H1 compliance.

Simplify achieving H1 regulations with Knauf Insulation’s free online H1 Calculator, upgraded to support version 6 H1 calculations.

Warm roof systems can be optimised for residential new builds — using accurate R‑value calculations, condensation risk analysis, and early technical input to achieve compliant, cost‑effective outcomes with confidence.

With roof surfaces exposed to high levels of solar radiation, material selection, colour choice and roof system design directly influence heat gain, internal comfort and cooling demand. 

A key strength Greenstuf brings to projects is early‑stage technical input. The team regularly assists with preliminary R‑value strategies, helping architects balance thermal performance with constructability and cost.

Instead of focusing solely on minimum compliance, Viking Roofspec systems are designed to enhance real‑world performance, helping buildings retain heat in winter, reduce overheating in summer, and deliver measurable long‑term value.

H1 insulation standard changes made in November 2025 have taken effect. Read on for a summary of key changes, and details of Mammoth Insulation's free modelling and calculation method service — a comprehensive service that considers H1 requirements, insulation build-ups and costs to deliver the best results for each project.

Meeting H1 insulation requirements comes down to flexibility — doing different things in different parts of the building envelope. Whether that's the roof, wall, slab or slab edges, PrimeTherm ERS (Energy Return System) PIR Insulation Board from Masons delivers maximum insulation at minimum thickness.

Foundation systems play a key role in thermal performance, particularly in slab-on-ground construction. When designed correctly, they can contribute significantly to achieving H1 requirements without the need for costly retrofits or redesign later in the project.

Porcelain tiles are highly effective in passive solar design (absorbing heat during the day, releasing at night), which assists in meeting the overall energy efficiency performance required by H1/AS1.

New MAXRaft Base and MAXSlab Base bring a more affordable insulated slab option to Kiwi projects, perfect for meeting the balance between cost-efficiency and thermal performance, while ensuring on-site efficiency.

A triple layer OSB rigid air barrier with an integrated R 0.41 thermal break, RigidRAP XT helps architects and designers simplify H1 modelling while strengthening and weather protecting the building envelope.

H1 Energy Efficiency requirements for residential buildings under 300m² focus heavily on insulation, glazing, and overall thermal performance. While these elements are critical, one key factor is often overlooked — moisture management within the building.

By combining airtightness, vapour control and passive ventilation into a coordinated envelope system, designers can achieve H1 compliant outcomes that are robust, buildable and comfortable.

For years, many residential designs could meet NZBC H1 by selecting products with the “right” nominal R-values and following a familiar recipe. That approach is now far harder to rely on.