Through Ecorate Ltd Keith Huntington provides a range of professional services relating to sustainability building, including NZ Building Code-H1 (Energy Efficiency) Compliance analysis (by the Modelling Method), and minimizing energy usage in buildings through their design and is able to provide objective analysis of passive building design effectiveness using AccuRateNZ computer modelling.

'AccuRateNZ' thermal simulation computer software was adopted by EECA (after substituting NZ climate data and living styles) for Government's former HERS (Home Energy Rating Scheme) programme.  This sophisticated design tool is used to analyse the energy requirements for each space in a dwelling for each hour of the day for each day of the year.  18 climate zones are used and the house can be analysed into up to 50 distinct volumes.  The hourly assumed design temperatures, throughout the year, for each of these volumes can be extracted if needed.  This data can be used as a Brief for the design of the heating/cooling systems which may be needed for the building.

If a building just achieves minimum NZBC-H1 compliance now, then in the future it will not comply as the Standards are revised over time. The original NZBC-H1 began in 1992, the second edition in 2000, and then the third edition in 2007. When will the next up-grade be.   NZBC-H1 is a minimum based on NZS 4218 rather than being 'best practice'.  In the future these mandatory minimums will be raised and it will be difficult and expensive to effectively up-grade, as is being realised with the current housing stock.

Keith is an accredited Homestar™ Practitioner, and also an accredited Homestar™ Assessor, (Reg#6868).  Homestar™ is an initiative of the New Zealand Green Building Council which provides a "...national voluntary environmental rating tool that evaluates the environmental attributes of New Zealand's stand alone homes.".  Some Territorial Authorities offer a remission of Rates if a minimum number of housing units are constructed it a particular minimum Homestar Rating.

Under the new Auckland City Unitary Plan, as notified on 30th September 2013, any development of 5 or more dwellings is required to achieve a Homestar™ 6-Star rating, or equivalent.  An AccuRateNZ analysis can be used to demonstrate the thermal performance aspects, with the added benefit of being able to go on to quickly give objective results for an exploration of alternative materials & constructions, and hence the cost implications of moving beyond minimal requirements.  The inter-relationship of insulation, glazing & thermal mass are connected as a multi-variable equation where the changing of one factor alters the influence of the others.

There are many urban myths surrounding passive solar design and sustainable architecture, especially with regard to insulation, glazing and thermal mass. There is no simple formula, (it is a multi-variable relationship), to define the ideal relationship between the three; instead each design, (in its location), needs to be specifically analysed. This is where Keith can, using AccuRateNZ and his experience, provide an objective measure of your proposed design, and suggest improvements that are practical, buildable and livable.

CONTACT DETAILS: Please feel free to contact Keith for his C.V. and summary of experience.    tel:  04 499-3015     mble:  021 890 251     e-mail:

Keith Huntington - B.Arch, Dip.Urb.Val, Dip Bus.Stud(Disp.Res), FNZIA, FAMINZ(Med), LEADR Registered Architect (RAB# 1372) and NZGBC Homestar™ Practitioner & Assessor (reg# 6868)