Membrane Roof Compliance: Specifying H1 Compliant Roofs for Projects
- Nuralite Waterproofing
- Apr 15
- 2 min read
Updated: Aug 26
With the recent changes to NZBC Clause H1, many designers are asking: how can I specify a compliant membrane roof on a commercial project?
As flat roof specialists with over 55 years’ experience, Nuralite provides system solutions that make achieving H1 compliance and reliable membrane roof compliance simple, efficient, and dependable.
Understanding H1 Changes for Membrane Roof Compliance
On 3rd November 2022, MBIE introduced fundamental changes to Clause H1 Energy Efficiency, focusing on the thermal performance of roofing elements, particularly insulation.
Minimum Roof R-Values for Buildings Over 300sqm:
Climate Zone | Previous | Current |
1 | R1.9 | R3.5 |
2 | R1.9 | R4.0 |
3 | R1.9 | R5.0 |
4 | R1.9 | R5.4 |
5 | R1.9 | R6.0 |
6 | R1.9 | R7.0 |
These changes have generated a significant increase in enquiries to our technical team. The common question: how can we ensure our roof designs achieve the new R-Values while maintaining complete membrane roof compliance?
Nuratherm Warm Roof System for Membrane Roof Compliance
Nuralite offers a tried-and-tested solution. Our CodeMark Certified Nuratherm Warm Roof System has been proven in the market for over 15 years and ensures you meet or exceed H1 requirements while maintaining membrane roof compliance.
Enertherm PIR Performance Values
Thickness (mm) | R-Value |
50 | R2.25 |
60 | R2.70 |
70 | R3.15 |
80 | R3.60 |
100 | R4.55 |
120 | R5.45 |
140 | R6.35 |
150 | R6.80 |
160 | R7.20 |
Achieving H1 Compliance Across New Zealand Climate Zones
Our 80mm Enertherm PIR board provides a continuous R-Value of 3.6 outside the structure. When combined with the NPM900 metal tray substrate, this creates an economical, fast-to-install, and fully H1 compliant roof for Climate Zone 1, achieving full membrane roof compliance.
For other New Zealand Climate Zones, we can adjust the PIR thickness to meet H1 requirements while ensuring continued membrane roof compliance.
To optimise efficiency, lofted insulation may also be included within the roof build-up, reducing PIR thickness while still maintaining full compliance.
Flexible Waterproofing Options for Membrane Roof Compliance
The Nuratherm Warm Roof System can be specified with either Nuraply 3PM or Nuraply TPO.
For added assurance, our team can perform a Hygrothermal Analysis specific to your project and location to confirm all H1 requirements are met, and full membrane roof compliance is achieved.
Explore the 3D Nuratherm Warm Roof Model
You can view our interactive 3D Nuratherm Warm Roof model on Working Spec to see how the system performs in practice.
Contact us today for expert advice on designing a fully H1 compliant warm roof while ensuring reliable membrane roof compliance for your next commercial project.
