H1 Energy Efficiency

Building Code Update - Energy Efficiency (H1)

Increased insulation requirements for warmer, drier and healthier buildings.

Energy Efficiency (H1) requirements

The Ministry of Business, Innovation and Employment (MBIE) has updated the Energy Efficiency (H1) requirements for insulating new homes and commercial buildings in the New Zealand Building code.

The purpose is to reduce energy needed to heat new buildings by up to 40% and help make them warmer, drier & healthier, with less impact on the environment.

New Climate Zones

With a focus on energy efficiency, these changes are explained first by introducing New Climate Zones.

This will allow the insulation requirements to better reflect the different temperatures experienced in each zone. MBIE has expanded the number of climate zones used in the insulation requirements to further divide into six.

Energy Efficiency for all housing and small buildings (under 300m2) 

MBIE has made changes to roof, window, wall and underfloor insulation.

The Building Code provides 3 methods for compliance:

1) The Schedule Method – Meet the minimum R-values provided

2) The Calculation Method – Meet the whole building Heat Loss parameter by calculating overall heat loss from all building envelope elements and allows trading off between elements so you can use higher R-values for some elements than the table shown and lower R-values for others

3) The Modelling Method – a calculation of the energy demand for the whole building using whole building calculation software

The new minimum thermal resistance values as noted in the schedule method, is summarised in table below:



Energy Efficiency for Large buildings (over 300m2) excluding industrial

MBIE has made changes to roof, window, wall and underfloor insulation requirements and issuing the new H1/AS2 and H1/VM2 for large buildings. This aims to reduce the energy needed for heating and cooling of 23% on average across new large buildings over previous minimum status quo requirements.

The new minimum thermal resistance values as noted in the schedule method, is summarised in table below:

For more information on these and other upcoming changes to the Building Code, please visit the 2021 Building Code Update section of the MBIE website.

When are the changes happening?

The changes were due to be implemented on the 3rd of November. However MBIE have issued a further extension for AS1/VM1 (for houses) until 1st May 2023. The implementation of AS2/VM2 and VM3 will still become mandatory on 3rd November 2022.

The previous Acceptable Solution H1/AS1 Fourth Edition Amendment 4, can be used to show compliance until 1st May 2023 and can be used for building consent applications submitted before 30th April 2023.

However, the higher insulation requirements can still be used today to demonstrate compliance with the Building Code, and MBIE has recommended that anyone able to build houses to the newer insulation standards are strongly encouraged to use them. This will result in a warmer, drier, healthier home that is cheaper to heat and in line with modern standards.

Start building now at new energy efficiency standards

For those who are currently building a new house it is possible to meet the new higher insulation requirements now, prior to the new rules coming into effect. It makes sense to future proof your build knowing what changes are coming.

At Knauf Insulation we have a range of products and solutions which can be mixed-and- matched to allow homeowners and builders to increase their energy efficiency levels.

At Knauf Insulation

Our state-of the art manufacturing facility for Asia Pacific has the capacity to confidently supply the New Zealand market through our key distributors and partners following the new requirements.

We are committed to supporting the build of healthier, higher performing homes in New Zealand alongside MBIE’s improved construction strategies. Using our global knowledge and local capabilities, our technical experts will bring innovative solutions best suited for the New Zealand Building Industry as we transition into the new Building Code requirements.

To keep up to date on the changes and to be amongst the first to hear about new products and solutions we'll be launching to help you meet the new requirements please register your interest below:

H1 Building Code update: Change for the better?

Our Specification and Regulatory Affairs Manager, Steve Smith explores the importance of H1 Building Code changes and provides some insight into benefits, further potential changes and implementation solutions.