Appliances (WoH) Overview

13/03/24 Please note this page is in the process of being updated and will be finalised shortly.



With the implementation of the NCC 2022 across most parts of Australia (see ABCB link), the NatHERS Scheme has introduced the modelling of Appliances (Whole of Home or WoH) for residential homes for energy-efficiency compliance.

This brings into the NatHERS process the assessment of the efficiency of a range of fixed appliances in a home, and requires a minimum level of performance to be achieved alongside the NatHERS Star-Rating in the form of a Whole of Home Rating to achieve NCC compliance.

In this guide the terms 'Appliances', Whole of Home and WoH are used interchangeable to represent this aspect of modelling.


NatHERS WoH in the NCC


NatHERS WoH Methodology

The basis of a NatHERS Whole of Home assessment is to specify the various required appliances in the project and achieve or exceed the required minimum WoH Rating to achieve compliance.

The framework has a comprehensive calculation methodology for these appliances for Australia homes based on substantial research and interrelation with other Australian energy-efficiency programs such as the GEMS (Greenhouse and  Energy Minimum Standards) Star-Rating standards.

The calculations involved in NatHERS WoH use a similar 


NatHERS WoH Appliance categories

NatHERS WoH focuses primarily on the major fixed appliances that are expected to be installed for a new dwelling. These categories include:

Category Regulated or non-regulated Further info
Heating and Cooling (HVAC) Regulated
Hot Water (HWS) Regulated
Cooking  Non-regulated
Lighting Regulated
Pool and spa pumps Regulated
Solar photovoltaic (PV) & Batteries Regulated
Plug-loads  Non-regulated


Regulated vs Non-Regulated Loads

The introduction of appliance energy-efficiency requirements in the NCC only assesses the performance of some categories of fixed appliances expected in a house, these are called Regulated Loads and effect the WoH Rating.

Some categories of appliances are modelled and calculated within the tool, but are Non-Regulated Loads, in that they are modelled but do not effect the final WoH Rating. These Non-Regulated Loads have been included to ensure that a more accurate and representative overall energy demand for the dwelling, including it's overall energy usage, running-cost and emissions, as well as to allow more accurate sizing of solar PV and battery sizing.


WoH Calculations & Results

As detailed further in the Appliance Results section


WoH Rating



WoH Compliance requirements



WoH Documentation requirements



WoH Certification

The introduction of WoH means that NatHERS Certificates have been updated for NCC 2022.


Training Requirements

Accredited NatHERS assessors must take further training in NatHERS WoH to be able to assess Whole of Home compliance. A free training program has been delivered for the NatHERS administrators


Supporting Resources

The below resources may be useful when assessing a Whole of Home project.




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