The Ministry of Business, Innovation & Employment (MBIE) has just released a proposal to alter the Building Code to increase the energy efficiency of new homes, as well as a raft of other improvements in terms of energy efficiency and housing densification. This is hugely significant as it will affect all councils across the country both in terms of well-being and regulatory enforcement. Therefore, we strongly encourage councils to make a submission on the proposal. Council input could come from building regulators, those in sustainability or policy, and anyone with an interest in this matter.

Winter temperatures in New Zealand homes often fall below World Health Organisation standards due to heat loss occurring through the roof/ceiling, walls, windows, floor as well as through drafts as shown in the diagram below. Therefore, MBIE is proposing a major change to the insulation standards for new homes to improve our buildings’ performance.



One of the key aspects to the proposed new standards is improving insulation. MBIE proposes dividing the country into six climate zones, rather than the current three. The reasoning behind this being that local climates are more nuanced than the current zoning allows for. For example, Queenstown and Nelson are both located in Climate Zone 3, though they have markedly different climates.




New Zealand insulation standards are currently a long way behind those of many other comparable developed countries. Another aspect of the proposal is to compare each of the six climate zones to the climates of other countries, and then make comparisons vis-à-vis their insulation standards required to maintain minimum indoor temperatures. For example, Climate zone 1 (Auckland) is similar to Adelaide, Australia and Climate zone 6 (Queenstown) is similar to Dublin, Ireland.



The proposal offers four options: the status quo, increasing each Climate Zone to standards half as good as their overseas counterpart, increasing the standards in each Climate Zone to be equal to their overseas counterpart and increasing the standard of each Climate Zone to be better than its overseas counterpart. The proposal presents the costs/investment in the document as well as the modelled energy savings. It also gives options regarding the timetable for introduction.



The climatic zones are from NIWA data on temperature and rainfall. MBIE’s proposals are to lift minimum levels of insulation to make buildings easier to heat and cool, so they will be warmer, drier, healthier and more energy efficient. Each zone will have different insulation and building requirements. In addition to changes to insulation, MBIE proposes updating to the Building Code to establish verification methods for Heating, Ventilation and Air Cooling (HVAC) systems in commercial buildings to reduce electricity load on the national grid, as well as alterations with respect to housing densification to ensure those living in apartments and high-rise buildings have adequate natural light, and a new proposal for improving weathertightness testing for higher-density housing.

MBIE informed the Taituarā Regulatory Reference Group that this consultation was being prepared last year, and Taituarā is preparing a submission on behalf of its members. We also strongly encourage all councils to make their own submissions on this proposal, and so we have already emailed our members working in this area. As council employees will be the ones at the coal face enforcing these standards when any changes come into force, it is vital that MBIE is aware of all issues which may arise so necessary alterations can be made prior to adopting these these amendments into the Building Code.

You can read the press release ‘MBIE Asks For Feedback On Insulation Requirement’ as well as access the consultation documents on MBIE’s website. The consultation is open until 28 May 2021.

If you have questions about this please contact Susan Haniel, Senior Advisor, Sector Improvement.