Articles in this issue


Welcome to the December 2016 NatHERS Star. The NatHERS Administrator has been hard at work since the last newsletter and we have a bumper issue to close out 2016.

Updated NatHERS Strategic Plan

There is now an update to the NatHERS Strategic Plan 2015-2018 available on the NatHERS website

NatHERS Governance Review Update

In 2016 the NatHERS Administrator engaged ACIL Allen Consulting to undertake an independent governance and operational review of NatHERS.

Invitation to Comment on the Software Accreditation Protocol Discussion Paper

A discussion paper has been developed to review opportunities to improve clarity and processes in the NatHERS Software Accreditation Protocol.

BERS Pro Accreditation Update

Having met all the outstanding requirements of software accreditation, BERS Pro is on track for full accreditation before the end of March 2017.

Quarterly stakeholder meetings

A recent initiative of the NatHERS Administrator has been to conduct quarterly stakeholder meetings with Assessor Accrediting Organisations (AAOs) and Software Providers.

NatHERS Technical Advisory Committee Update

To keep everyone better informed about the discussions of the NatHERS Technical Advisory Committee (TAC) we will be providing updates in this, and future, editions of the NatHERS Star.

NatHERS Trademarks

Over the past few years the NatHERS Administrator has undertaken a trademarking process to protect the NatHERS logo, name and acronym from misuse. 

Get to know: Chenath

Did you know the Chenath Engine has been around in different forms since the 1950s?

On the Horizon

2016 has been a busy year for the NatHERS Administrator and 2017 looks set to follow suit.

BDAV Design Contest

The Building Designers Association of Victoria (BDAV) has revamped its 10-Star Sustainable Design Challenge.

New energy-saving guide for Northern Australia

Recently the team behind the Your Energy Savings website released the Energy-saving guide for Northern Australia

CRC LCL – Next Generation Rating Tools

The CRC for Low Carbon Living, in association with project partners CSIRO, Energy Inspection, and the University of South Australia, launched the RP1024 NextGen Rating Tools project in Adelaide on 29 September 2016. 

Get to know: Chenath

Did you know the Chenath Engine has been around in different forms since the 1950s? Over the years a large number of very clever people have worked on improving it and it has evolved along the way. It has also had a number of different names and fed into different programs.
Behind the front end software (FirstRate5, BERS Pro, and AccuRate) and based on agreed rules, Chenath works hard to model the thermal comfort of a home. It uses the historical weather data for 69 different climate zones, along with the building orientation, construction types and materials, windows/doors, and eaves/shading/curtains. It also assumes windows are opened and closed at times when temperatures inside or outside are appropriate. Chenath uses all of these factors to calculate the amount of energy required to keep a home at a comfortable temperature.
There are a number of complicated calculations that Chenath uses to work out when a change in temperature is needed in different rooms of the house (otherwise known as a zone type), for different climate zones. The different zone types help to predict the behaviour of residents in that room type. For this reason it is important that the zoning of a room reflects how the room will be used. If you would like to know more about how to zone a house, please have a look at the zoning examples on the NatHERS website.
Chenath is an intelligent and complicated piece of software and getting to know the way it works can be very helpful for assessors when calculating ratings. To help people better understand Chenath, the CSIRO have recently released a repository of documents outlining much of the detail of how Chenath calculates ratings. While targeted at a technical audience, the repository provides a lot of information about the underlying assumptions that Chenath makes and explains concepts like the Area Adjustment Factor.
For more information on how the software works see:

  1. How NatHERS Star Ratings are Calculated
  2. Chenath Repository
  3. The NatHERS explainer video