Specialists in NatHERS assessments & BASIX certificates

passionate about working towards a sustainable future

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Specialists In NatHERS & BASIX

Needing a NatHERS Thermal Performance Assessment or BASIX Certificate ? Want to save thousands of dollars on construction and energy costs ? Then you’ve come to the right place

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Needing a NatHERS Thermal Performance Assessment or BASIX Certificate in Newcastle or Sydney? 

Want to save thousands of dollars on construction and energy costs? 

Then you’ve come to the right place. Goal Zero specialise in thermal performance assessments, offering quick 1-5 or 6-10 Business day completion options and value for money service. 

We can model your property in our approved BERs Pro software and advise ways to make your development more energy efficient right from the start.

Our Core Values

Great Services

A trusted partner in energy efficiency, in thermal comfort assessment and sustainability.

Highest Standards

With formal qualifications and experience in thermal assessment is what you can rely on.

Professional Team

A well-known and respected figure in the building and construction industry that you can rely on.

Creative Solutions

An impressive knowledge of the regulations to meet compliance and the software systems.


BASIX or Building Sustainability Index, is a NSW Government planning online assessment tool. BASIX’s primary goal is to reduce household energy and water usage and optimise thermal performance by setting minimum sustainability targets for new and renovated homes. BASIX is made up of three assessments:

  • Water usage – This considers the amount of lawn/garden area, roof catchment area, water tank size, water usage ratings of taps/toilets etc.
  • Thermal Comfort – This is how energy efficient your property is, this can be done using a Do-It-Yourself method, or by a NatHERS assessment.
  • Energy usage – This takes into account what appliances you will install, light fixtures, air-conditioning, if photo voltaic panels (solar panels) will be used etc.

BASIX sets minimum sustainability targets for water and energy consumption and the thermal performance of all residential dwellings that must be achieved before a BASIX certificate can be issued.
The performance targets set by the NSW Government include:

  • up to a 40% reduction in potable water consumption
  • up to a 40% reduction in greenhouse gas emissions AND
  • minimum performance levels of thermal comfort.

The BASIX certificate benchmarks of water and energy usage are both measured on a per capita basis, including:

  • Water – the average NSW consumption of potable water from the residential sector.
  • Energy – the annual average NSW greenhouse emissions from the residential sector.

A BASIX certificate is the hard copy document generated from the online energy and water assessment tool that outlines all the sustainability commitments that must be adhered to in your build. Commitments such as shower/tap/toilet ratings, water tank size, lighting type, hot water system, air-conditioning type and rating, exhaust fans, dishwasher, fridge, freezer, washing machine, dryer ratings and what type of cooktop/stove will be installed (gas/ electric). This document is evidence that your development plans meet the BASIX requirements and must be included in the development application to council.

The Nationwide House Energy Rating Scheme (NatHERS for short) is a star rating system out of ten stars, that rates the energy efficiency of a home. The more stars the more energy efficient your home is. NatHERS takes into account all elements of the home including, but not limited to its location and orientation, construction materials, glazing, insulation, exterior colours of walls and roofs, how each room of a dwelling will be used (day time/night time), ventilation and overshadowing from neighbours to estimate its heating and cooling energy use. NatHERS helps to make Australian homes more comfortable for their residents and also helps to save on energy bills. An accredited NatHERS assessor can provide expert advice on different construction materials and offer design advice to ensure that you can achieve the maximum thermal comfort levels within your budget.

A NatHERS certificate is the hard copy document that lists all the information that was inputted into the software to model the dwelling. This includes windows (types, performance, shading and location), walls (material, area, colour, insulation), floors (location, type, area, sub floor ventilation, insulation and floor coverings), roof (type, insulation and colour), ceiling penetrations (exhaust fans, downlights, chimneys etc). It also lists the details of the assessor, the date of the assessment, the dwelling details and the annual thermal performance loads (MJ/m2). This certificate could be used at a later date to increase the value of your home by proving how thermally efficient your dwelling is.

A NatHERS assessment offers an alternative to the DIY BASIX method to complete the thermal comfort section of BASIX. A BASIX assessment looks at each component of a house separately i.e. room by room. This can make it difficult to achieve a pass without specifying high performance materials such as double and even triple glazed windows, this can very quickly increase construction costs and force you to compromise on aesthetics. The BASIX assessment tool is also very restrictive, nominating different aspects of the construction for you including what level of insulation is needed or what type of glazing you must use.

NatHERS on the other hand models the whole house as one, rather than room by room. A NatHERS assessment is a lot more thorough in its modelling and also offers a greater amount of flexibility to reduce energy loads by allowing the rating of one room/zone to compensate for another therefore, providing more cost effective options to achieve compliance. A NatHERS assessment also inputs more detailed information of the dwelling to be constructed, meaning that you can be assured that the NatHERS model will more accurately reflect real world performance.

BASIX is for NSW Development Applications only. BASIX is required on all new residential developments including houses, dual occupancies, townhouses or villas, granny flats and apartments. It is needed on alterations and additions to dwellings that cost $50,000 or more, and for the installation of a swimming pool greater than 40,000 litres. A BASIX is required before you lodge your DA with council.

A NatHERS assessment is used in the thermal comfort section of the online BASIX tool. Instead of using the DIY method, an accredited NatHERS assessor can perform a more thorough thermal assessment on the dwelling to be constructed.

Other states and territories outside of NSW use the NatHERS star rating out of 10 to show compliance. The NCC (National Construction Code) deems all new residential dwellings achieve a minimum star rating of 6 stars using NatHERS approved software. These ratings are being reviewed all the time and getting a pass is only becoming harder to achieve. Goal Zero Thermal Performance Assessors are nationally accredited and are fully licensed to use NatHERS software. So, if you’re struggling with compliance, give us a call today.



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