An assessor:

• uses prepared building plans and/or on-site measurements and software tools to model how well a house will perform in hot and cold weather and how efficient it will be to run.

• provides recommendations on how homes can be more energy efficient and comfortable to live in.

NatHERS New Build/Renovation/Addition assessments are usually done from the office, but can also involve visiting building and construction sites. NatHERS Existing Home assessments initially take place in  the client’s home.

NatHERS for New Home builds and major renovations or additions can:

• show that the new home will meet National Construction Code (NCC) energy efficiency regulations for building permit applications
• advise home owners, architects and builders on the thermal performance and energy efficiency of various house designs

NatHERS for Existing Homes can:

• advise home owners and renters on the energy efficiency of their home and suggest improvement options
• advise prospective home buyers/sellers on the thermal performance of a home they are interested in buying/selling
• identify and prioritise retrofit activities and the impact of varoious upgrades (including adding PV solar) on energy bills and thermal comfort

NatHERS Existing assessments are not used for regulatory purposes in Victoria, and many other States,  as yet.

The 2022 NCC requires all new Australian houses and apartments to meet a minimum energy efficiency rating of 7 stars under NatHERS, alongside a Whole of Home energy performance rating of 60 out of 100. The Whole of Home assessment considers the energy required for the whole home, including heating and cooling and hot water systems, pool/spa pumps, lighting, on-site energy generation and storage (solar panels and batteries), cooking and plug-in appliances.

The new energy efficiency standards became mandatory in Victoria on 1 May 2024. The regulations require assessors to have documentation above what was previously provided, such as details on the appliances being installed, their energy efficiency and solar PV systems.

For NatHERS New Homes:

• a set of drawings containing, at a minimum, site plan — including a north point (true north), floor plan/s (including zones), elevations, sections, construction material details, lighting location plan/electrical schedule (including penetrations eg exhaust fans, vents, rangehoods and ceiling fans), window, skylight, roof window and door schedule/details including size, glass and frame type, opening style, location. The location and heights of neighbouring dwellings or infrastructure that may affect shading is also needed.
• a signed contract and written permission to proceed. 
• For NCC2022 Whole of Home, additional info is required - details of fixed appliances (eg. type, model, efficiency) and solar PV systems if to be installed
• if any of the information is not available, a worst case/default scenario is modelled, but guidance can be given.

For NatHERS Existing Homes:

• access to the whole home to collect evidence and information, including roof space and subfloor, external shading.
• a signed contract and written permission to proceed.
• useful to have (but not essential) recent energy bills or access to smart meter data, any floor plans/plans of the house, information or specifications on construction materials, insulation, hot water, heating and cooling appliances (eg age, condition, star rating).

For NatHERS New Homes:

• Generally turnaround is within the week, as long as all documentation is provided at the initial request. A preview Certificate and Report is sent to the client before the Final Certificate is created, based on feedback and results.

For Home Energy Rating Existing Homes:

• The actual on site assessment takes around 2-2.5 hours, depending on the size and complexity of the house. Further work in the office is required to generate the final Certificate. The final Certificate is sent within a week of the assessment.

For NatHERS New Homes:

• Depends on the size of the home and the complexity of the design and the number of revisions. Generally, final assessments are around $800, including report and running optimisations based on client feedback. Contact me for a quote.

For Home Energy Rating Existing Homes:

• This is an evolving space. It will be between the previous RES Scorecard cost ($350-$450) and the cost of NatHERS new homes, depending on the size of the home and whether a Certificate only is required, or a more detailed optimisation. Contact me for a quote.

For other work outside of or additional to the NATHERS assessment process:

• I charge an hourly rate, please contact me for more information.

As early as possible!

• Having an assessment done before you buy/rent/renovate/retrofit can help identify potential issues around cost and comfort, and help save money and stress.
• Thinking about thermal performance and energy efficiency early on in a new home design and build can help produce a better outcome and future asset.