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Home energy assessments and ratings

Which do I need: NatHERS, Home Energy Rating or BASIX?

Still on plans? We can assess a new home or major renovation anywhere in Australia. Already built? We visit the home, currently mainly in New South Wales and Victoria. Building or renovating in NSW? You may also need BASIX.

Official guidance checked 1 September 2026Requirements can change by location and project. We explain the likely pathway, but your certifier, council or approval authority confirms what is required.
Start with the home

Match the assessment to the project stage

New homes and major renovations

NatHERS design assessment

Still working from plans? A NatHERS assessor models the proposed home before construction. This can cover the thermal Star Rating and, where required, Whole of Home.

Important limit

Your certifier or approval authority confirms the current rules for the state or territory.

What to have ready
  • Current floor plans, elevations and sections
  • Construction, insulation, glazing and shading specifications
  • Orientation, site details and proposed fixed appliances
  • The certifier, council or approval pathway requirements
What you receive

The relevant NatHERS certificate and design feedback, subject to complete documentation and the applicable approval pathway.

See how it worksCheck the official NatHERS new homes guidance
Homes that are already built

Existing-home Home Energy Rating

Want to understand how your current home performs and what to improve first? An assessor visits the property and provides two ratings, estimated energy use and practical upgrade guidance.

Important limit

This is for a completed home. It is not the certificate used to prove new-home building-code compliance.

What to have ready
  • Access to the home for the required assessment
  • Existing building fabric, windows, shading and orientation
  • Current heating, cooling, hot water and other fixed appliances
  • Known renovations and the household decision the rating should support
What you receive

A certificate with a Home Energy Rating from 0 to 100+, a Star Rating from 0 to 10, modelled annual energy use and practical upgrade guidance. Modelled results do not guarantee actual bills or savings.

See how it worksCheck the official existing homes guidance
NSW residential development

BASIX assessment support

Building or renovating in NSW? BASIX is part of the planning process. It covers water, energy, thermal performance and materials, and the certificate needs to match the submitted plans.

Important limit

BASIX is specific to NSW. It generally applies to new dwellings, alterations and additions costing $50,000 or more, and swimming pools of 40,000 litres or more. The Planning Portal confirms the current rule.

What to have ready
  • NSW Planning Portal project and development details
  • Plans, areas, construction and glazing specifications
  • Water, landscaping, pool and fixed energy system selections
  • The nominated thermal performance method and approval pathway
What you receive

BASIX inputs, commitments and certificate support relevant to the project scope. Final submission requirements remain subject to the NSW Planning Portal and consent authority.

See how it worksCheck the official NSW BASIX guidance
A common distinction

Whole of Home is a new-home rating

Whole of Home is the 0 to 100+ measure on a new-home certificate. Existing homes now receive a Home Energy Rating from 0 to 100+. Keeping these terms separate helps prevent the wrong certificate being used for a project.

Understand Whole of Home
Business sites

Commercial work starts with the scope

An office, shop, warehouse and industrial process do not need the same audit. Start with the site, available energy data and the decision the report needs to support.

Explore commercial energy assessments
Victorian rentals

Understand the 2027 to 2030 energy standards

Heating, cooling, hot water, showerheads, ceiling insulation and draughtproofing have different dates and triggers. A rating can help with planning, but it does not prove legal compliance.

Read the rental standards guideRequest a property review
What happens next

From the first call to a useful result

  1. 01

    Tell us about the home

    We check the location, project stage and what the assessment needs to help you do.

  2. 02

    Gather the right information

    For a design, that means current plans and specifications. For an existing home, it means safe access to the property and its fixed systems.

  3. 03

    Assess and clarify

    The assessor records the evidence, explains any missing details and tests relevant options where they are part of the scope.

  4. 04

    Receive the agreed result

    You receive the certificate, rating or guidance named in the quote, together with the important assumptions and limits.

  5. 05

    Tell us if the project changes

    Changes to plans, products or the home can affect the result, so the assessment may need to be checked again.

NatHERS boundary

Assessment expertise does not replace the approval authority

A valid NatHERS certificate uses accredited software and the relevant assessor pathway. The certifier, council, consent authority and current building rules determine what evidence the project must submit and accept.

Read the official NatHERS scheme overview
BASIX thermal methods

Choose the method that fits the NSW project

NSW guidance provides DIY, NatHERS simulation and Passive House methods for eligible project types. Complex and multi-dwelling projects may require simulation using NatHERS accredited software.

Confirm the official thermal performance methods
Not sure where to start?

Tell us what you are working on

The five-minute call checks the location, whether the home is built or still on plans and what result you need. It is a simple logistics call, not the assessment itself.

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