Exceeding the minimum

The aim of this programme is to help consumers and the building industry understand that the standards are a minimum only and that there are real benefits to exceeding them. Better information about options creates the opportunity to consider higher-performing buildings and help create a more responsive market, with industry more able to meet consumer expectations, aspirations and needs.

The critical success criteria for this programme include:

• consumers and industry understand that the Building Code and standards are a minimum that must be met but can and should be exceeded
• the benefits of exceeding the minimum can be clearly articulated based on meaningful terms
• the barriers to exceeding the minimum have been addressed
• consumers expect and demand buildings and communities that perform to a higher standard
• the industry delivers buildings and communities that perform to a higher requirement in a cost-effective way.

To find out more about this research programme, please contact zerocarbon@branz.co.nz.

Research under this programme

Consumers and industry understanding that the minimum can be exceeded

Measuring our sustainability progress

This is the second project of its type, the first having been undertaken in 2013. It uses a consistent, repeatable method to quantify indicators of stand-alone house performance (such as simulated thermal performance) based on consent documentation. It shows the extent of exceeding the minimum features in house consents (within the limits of calculated indicators). The results of the second study were also compared with results from 2013. You can read more in the study report SR483 Measuring our sustainability progress: New Zealand's new detached residential housing stock (second update) and a series of fact sheets.

Accurately calculating thermal performance in timber-framed medium density housing across New Zealand

The aim of this project is to recommend a method or methods taking into account accuracy and viability. Rule-of-thumb wall timber content can be approximately half as-built timber content in walls, with consequences for the thermal performance of the wall. Current methods for calculating wall thermal and moisture performance are inadequate for more complex construction assemblies. This project compares alternative calculation methods for wall construction R-values and assesses how rule-of-thumb and as-built timber content in walls affects thermal performance.

How do we encourage consumers and industry to exceed the minimum?

• Aim is to look at models of change which can be applied to construction industry practice and consumer behaviour.
• It will produce a plan of how findings can be implemented into actions.

Articulating benefits of exceeding the minimum

Quantifiable evidence for building beyond Code

The aim of this project is to develop an evidence base showcasing the benefits of exceeding the minimum with respect to energy and thermal performance. It will provide definitions of Code, better and best thermal performance, which will inform the basis of the assessment. A comparison of the New Zealand Building Code and New Zealand voluntary thermal performance requirements will be made with international standards.

Who benefits from exceeding the minimum and which standards can be exceeded to provide benefits?

The aim of this project is to ascertain the standards that are already being exceeded, the types of houses in which these standards are being exceeded and who would most benefit from this. It includes an industry survey (500 responses) on housing quality, building standards in New Zealand and experiences of exceeding the minimum and assesses institutions and structures in the exceeding the minimum space in terms of power, incentives and behaviours.

Tools for young people to understand how they can improve home performance

The aim of this project is to help young people as house occupiers now and as future tenants and house purchasers. Work will include building understanding and selection of a trial group or groups (in areas where there is a supportive environment that can help families obtain advice and take steps to improve house performance). Home Performance Advisor training materials will be tailored to suit delivery to young people and prepare trial groups for working in regions. Regional teams will pilot this in schools, and the pilots will be evaluated and teaching tools refined with findings and outcomes reported.

Addressing barriers to exceeding the minimum

Doing better - assessing recent New Zealand research for impact

Exceeding the minimum is defined as exceeding standards in the New Zealand Building Code and/or demanding dimensions of performance not currently specified in the Building Code. Dwelling access and functionality is currently limited in the Building Code and excluded from application to private residential dwellings despite evidence that this is crucial to ageing societies.

When performance is not specified in the Building Code, it is problematic because the minimum is effectively zero. Lack of recognition in the Building Code means lack of industry take-up and poor research investment. A lack of recognition, research underinvestment and low industry take-up leads to a lack of research being cited as a reason not to incorporate requirements into legislation.

New Zealand and international research shows that a concerted, multi-pronged approach is necessary to achieve outcomes that exceed the minimum. This should include a regulatory framework, industry incentives and development, consumer education and accreditation, and sufficient investment. The view that the construction industry cannot innovate is false. To improve industry take-up, net benefits must be demonstrated and solutions should be 'plug and play'.

The choice to exceed

This uses a qualitative, social research method to look at current industry advice and messages to consumers about exceeding the minimum for new-build dwellings. Focus groups were held in Christchurch and Wellington on consumer experiences. An industry focus group was also held on experiences of dealing with consumers about exceeding the minimum. Consumers conveyed an inability to access relevant information and a lack of confidence and trust in building professionals.

Building to rent

Homeownership levels are falling. An increasing number of New Zealanders are spending long periods in rental accommodation. The aim is to assess whether new rental housing should be developed based on different models including consideration of a shell and fit-out model, establishment of real estate investment trusts and use of energy performance certificates.

When is ‘good enough' not good enough?

This project will collect information and opinions from consumers about what they understand by minimum standards. It includes a survey of experiences of refurbishing houses to beyond Building Code level and assessment of the value consumers place on upgrade options.

Getting the stated performance in higher spec'd windows - tackling the window-wall junction

The aim of this project is to give confidence to industry by providing workable solutions through compilation and identification of potential solutions. Most promising solutions will be constructed, tested for buildability and thermal/weathertightness. The best performing solutions will be converted to drawings as an industry resource.

Consumers expect and demand buildings that perform to a higher standard

LCAQuick - Residential

This project developed a tool for calculating life cycle environmental impacts (including climate change) of dwellings during design. This was based on modification of the original LCAQuick - Office tool. Work included development of embodied environmental impact data for materials and development of reference residential buildings.

Understanding life cycle design

The aim of this project is to provide support and training to architects and engineers who want to incorporate life cycle assessment into design using LCAQuick. It involves webinars, working with tertiary education institutes to get building LCA included in course materials and development of case studies for which the life cycle environmental impacts have been calculated during the design and build process.

Delivering buildings that perform to a higher requirement in a cost-effective way

Retrofitting insulation in residential properties

This project sought to understand where consumers and landlords obtain advice about insulation and how they judge the credibility and quality of the information/advice they receive. It explored the factors that consumers take into account when making decisions about insulation and provides recommendations on how advice to landlords and homeowners may be improved.

Updated: 23 November 2023