Submissions due: 28 May 2021. Building Code for better homes and buildings

As part of the annual Building Code update process, the Ministry of Business, Innovation and Employment (MBIE) is asking for feedback from Kiwis about what changes we need to make our homes and buildings healthier and more efficient. MBIE wants to know how far changes should go, and how fast they should be implemented. We’ve been calling for improvements to the Building Code for many years and we invite you, our members, to join us in demanding better outcomes for Aotearoa’s buildings, and the people in them.  

The Building Code update 2021 consultation has six proposals. The first proposes improvements to insulation requirements to achieve greater energy efficiency for homes and small buildings, and the second focuses on large buildings. We plan to provide comprehensive feedback on these two proposals as well as commenting on proposals three and four which address heating, ventilation and air-conditioning systems in commercial buildings and natural light for high-density housing.  

The first thing we will make clear to MBIE is that we are surprised and disappointed that the proposals for changes to the Building Code do not align with those of the Building for Climate Change (BfCC) programme. The changes proposed for the H1 Energy Efficiency clause of the Building Code are based on fixed R-values for insulation, but the BfCC proposals are performance based (kWh/m2 of heating demand). Not only are these two approaches ‘apples and oranges’, but NZGBC’s preliminary modelling shows that the proposed first cap in the BfCC programme is less stringent than those in two of the proposed options for the Building Code.

This could mean the implementation of the BfCC programme leads to an unintended reduction in the insulation required and inevitably, confusion and frustration for industry.

We expect better from government and from policies and regulations that are meant to work together to lift our buildings to an acceptable standard.

Lifting standards for homes

In the first proposal the consultation paper recommends lifting minimum levels of insulation to make homes more comfortable and easier to heat and cool. It also introduces a new climate zone map to better recognise variations in climate around New Zealand (and reflect this in the proposed requirements).

The paper gives three options for increasing the minimum thermal insulation requirements from what they are now:

› Option 1. Halfway to international standards – Increase the minimum insulation to a level that is approximately half of that from other parts of the world with similar climates. This represents a modest increase in insulation levels versus the current minimum settings and would still leave New Zealand considerably behind other countries.

› Option 2. Comparable to international standards – Increase the minimum insulation to a level that is comparable with other parts of the world with similar climates. This represents a moderate level of change versus the current requirements and would significantly reduce energy demands for heating and cooling.

› Option 3. Going further than international standards – This is the greatest level of increase proposed. This would put New Zealand’s minimum insulation levels ahead of other parts of the world with similar climates. It would have the greatest impact on current construction requirements and the biggest reductions in energy use.

Setting a goal of lifting standards only halfway to comparable international standards is completely unacceptable to NZGBC and it should be completely unacceptable to government, to industry and to the New Zealand community.

Forty percent of New Zealand’s existing homes are damp and mouldy and according to OECD standards, New Zealand homes are poorly constructed and heated, and standards are less stringent than those of many other OECD countries. Option 1 should only be considered as a stepping stone – to be achieved within a short timeframe – towards what we need and deserve for New Zealand homes. We need, at the very least, to be truly comparable with international standards that are recognised as appropriate and fit for purpose, if we are to build the healthy homes Kiwis deserve. We need to go further than comparable international standards if we want to achieve the energy efficiency that will help us achieve our emissions reduction targets and if we want to reduce energy bills for kiwi households.

The case for Option 3 and beyond

We have so much to gain from choosing Option 3, and ultimately, from aiming even higher. The description of Option 3 indicates our minimum standards for insultation would be lifted beyond those of comparable countries, but this is only partly true. Analysis in the consultation paper shows that some of the requirements would surpass the requirements of countries used as comparisons (Australia, England, Wales & Ireland, and California). However, even at Option 3, some of the proposed requirements will barely meet some of these countries’ requirements, let alone surpass them. In the analysis of Option 2, it is clear that some of the requirements, particularly for underfloor and wall insulation, will fall well short of the standards required in the comparable climate zones.

Some of the reasons for demanding Option 3 include:

  • New Zealand has an energy equity problem. Too many households must spend high proportions of their incomes heating cold, inefficient homes. If we are serious about tackling poverty and improving the lives of all Kiwis, we must ensure our future housing stock does not shackle households to high energy bills.
  • According to health statistics, 20 New Zealand children are dying every year, while another 30,000 are hospitalised from issues related to poor housing. We can’t afford for our new homes to become the cold, damp unhealthy homes of the future because of a woefully inadequate Building Code.
  • New Zealand has a clear and legislated goal of achieving a net zero carbon economy by 2050. If we are to achieve this, we must make drastic improvements to energy efficiency in our homes and reducing carbon emissions related to the housing sector.
  • The housing sector represents a huge opportunity for improving energy efficiency and reducing the nation’s energy demand. If we significantly improve energy efficiency in new homes, we will help to reduce peak demand, free up energy capacity for new technologies such as electric cars, and reduce the urgency for developing new energy generation.
  • While there may be some initial challenges for manufacturers and suppliers, lifting minimum standards will create opportunities to provide the materials we need to achieve better outcomes.

Our submission will detail the reasons for why Option 3 is the only acceptable option and how we can get there and beyond. Committing to Option 3 will provide the shake-up that our industry and housing sector desperately needs. This will be welcomed by many, but we do recognise that the changes will be daunting for many others, especially in a housing market already under acute pressure due to supply issues and high costs.

To make the journey smooth and successful, we need to balance the urgent need for action with a reasonable lead-in time and excellent preparation. Industry will need great communication, as well as an information and training programme that will hit the road to map and explain the changes ahead for everyone impacted, from architects and designers to builders, manufacturers and suppliers.  

Beyond insulation

Tackling insulation is critical, but it isn’t the only factor in warm, dry, low carbon buildings. While Option 3 will get our homes a long way towards where they need to be, the current H1 proposals are missing a host of other issues:

  • Neither airtightness nor thermal bridges are addressed. These become proportionately more important as insulation levels ramp up.
  • Other elements such as heating, hot water efficiency and lighting efficiency which also affect energy use and carbon emissions are not mentioned.
  • Ventilation and internal moisture are not addressed. The current proposals risk perverse outcomes if these factors are not considered alongside insulation.

Some of the above issues will hopefully be addressed by the Building for Climate Change team, but this will only work if the left hand at MBIE talks to the right hand and these two programmes are properly coordinated.

We will raise these points in our submission along with how government can optimise and align policies for the best possible outcomes in relation to proposals one to four. We will also make suggestions for technical improvements to existing and proposed regulations and standards.

If you or your organisation would like to provide input to NZGBC’s submission to MBIE, please contact Sam Archer ([email protected]) as soon as possible.

We plan to release a draft submission around mid-May to prompt any further input from members, and to make our position clear should any of you wish to support our submission or make your own. The Building Code update 2021 consultation closes on 28 May 2021. For more information, please visit

Source: NZGBC