Developing a residential rating tool

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Beacon believes that a residential rating tool is vital to address New   Zealand’s poorly performing houses.

Defining the problem

New Zealand’s homes are on average 6ºC below World Health Organisation recommended minimum temperatures and 45% have mould issues. Insulation estimates indicate that 250,000 houses either have no ceiling insulation or insulation in less than half of the roof area, 700,000 houses have no (or little) wall insulation, and 740,000 houses with suspended floors have no underfloor insulation.

What’s more, our homes are seriously resource inefficient, consuming vast quantities of water and energy to operate at less than optimum levels.

These problems have been clearly identified in Beacon’s National Value Case for Sustainable Housing and the Better Performing Homes for New Zealanders: Making It Happen report by the New Zealand Business Council for Sustainable Development.  Both reports quantify the benefits of upgrading our housing stock:

  • For homeowners and tenants: healthier living, lower medical bills, greater warmth and comfort, lower household power and water bills, a more valuable asset
  • For industry: greater demand for products and services
  • For banks: less risky security and healthier mortgage payers
  • For New Zealand’s economy: more jobs in the renovation market and associated industries, lower health and social costs, greater productivity from healthier New Zealanders, greater efficiency from water and energy resources, reduced need for more infrastructure (dams, power stations, lines), better resilience to changes in climate and population growth: more capacity through greater efficiency


How will a rating tool help?

A residential rating tool provides the extra momentum necessary to convince New Zealanders to take action and improve the performance of their homes.  It will allow homeowners to assess their home’s performance and, importantly, reflect the value of improvements.  International research reveals that homes with performance ratings sell quicker and for a higher value than non-rated homes.

A residential rating tool can:

  • provide a prioritised plan of solutions to improve the performance of the home
  • be an independent and credible system to compare the performance and quality of a home at the point of purchase, upgrade or rental
  • provide an incentive to invest in upgrading a home to achieve higher performance levels, giving an indicative value to the upgrades undertaken
  • reduce the demand on precious energy and water resources
  • generate data to assist Government in understanding the challenges that exist in the current housing stock, and target solutions.


New Zealand’s rating tool: Homestar™

A joint venture between BRANZ the NZ Green Building Council and Beacon Pathway has developed a single residential rating tool for New Zealand’s homes - Homestar™.  It utilises Beacon’s research and renovation tools developed during the HomeSmart Renovation project.

Homestar™ is unique as it covers both new and existing homes - many overseas countries operate multiple rating systems which focus purely on new builds - and it offers credible independent advice about what needs to be done to a house to improve its rating.  This advice can be prioritised by cost, health, comfort and environmental outcomes into a plan to improve the quality and performance of their homes.

A simple, free self-assessed version of the rating scheme, offering 0-4 stars, is available online.  A Homecoach can be engaged to assist with the simpler rating, and trained Homestar assessors can provide a fully certified rating.  Tthe rating system is supported by Homestar™ Practitioners who can provide individual advice on improving a home’s performance.

Now run by NZ Green Building Council, Homestar can be found at

Of course, much of this change must be driven by consumers who need to value a home’s performance as much as they do its location and aesthetics. Demand for well-performing homes will increase with consumers’ understanding of the features and benefits of sustainable housing, and the real estate industry must be ready to respond with the use of a home rating tool.


  • 31-May-2010 (Presentation PRES/22)

    New Zealand's Residential Rating Tool (PDF 3.6MB)

    Verney Ryan

    Beacon Research Symposia 2010

  • 30-Apr-2010 (Conference paper PUB/8)

    The Residential Rating Tool: Looking Back to 2010 - New Zealand, You've Come a Long Way (PDF 252KB)

    Verney Ryan

    SB10 New Zealand

  • 28-Jun-2009 (Report )

    Development of a Single Residential Rating Tool for New Zealand (PDF 1.5MB)

    Produced by New Zealand Green Building Council, BRANZ and Beacon, this scoping report sets the scene for the development of a single rating tool for new and existing homes in New Zealand. It investigates why New Zealand needs a rating tool, what criteria it could include, options to ensure wide scale efficient delivery, and most importantly how this could help improve the quality and performance of New Zealand housing stock while setting a best practice benchmark for new housing. 

  • 11-Jun-2004 (Report PCP/14)

    Sustainability Framework Benchmarking Report: NOW Home versus REF Home (PDF 737KB)

    Roman Jaques, Barbara Nebel, Robert Vale, Katja Lietz, John Storey, Louw van Wyk, Bob Frame

    This early report was commissioned for the Project Confirmation Phase.  It describes and compares the sustainability features of the Waitakere NOW Home® to a typical house (Ref Home).  It then develops a practical decision making framework to assess key sustainability issues with the aim of later developing tools for future rating systems.  Work in this report formed the basis for later work on a rating tool for New Zealand.

Logo, Homestar