BASIX Update 2023: How Will it Affect Your Residential Projects?

6 minutes read

The NSW (New South Wales) Government is committed to achieving net zero emissions by 2050. This commitment has further impacted BASIX (Building Sustainability Index) by increasing the BASIX standards for energy use and thermal performance for new homes in New South Wales.

The changes in the BASIX regulations are forecasted to significantly impact the approvals, schedule, and costs of residential construction projects.

Each home or other residential project must have a BASIX Certificate specifying its energy efficiency and thermal performance. The upcoming changes include updating the existing BASIX standards to improve homes’ thermal performance further.

Read further to know how BASIX works and how the 2023 update will affect your residential projects.

How Does BASIX Work?

With increasing energy costs, every homeowner is trying to make their home as energy-efficient as possible. Simultaneously, the New South Wales (NSW) Government is making all possible efforts to ensure that all new homes constructed in the state adhere to the new BASIX standards.

The BASIX Report and certificate basically measure how energy efficient a home is. The upcoming BASIX scheme updates will ensure the NSW government is on track to meet energy efficiency and emission reduction targets by 2050. It includes reducing water and energy consumption in various measurable ways.

Under the new rules, the BASIX standards will be updated to improve homes; thermal performance.

The fundamental changes to the existing BASIX scheme include increasing the thermal performance standard from an average of 5-6 stars to 7 stars NatHERS rating and an increase of approximately 7 to 11% in greenhouse gas reduction. The updated BASIX regulations will come into effect on October 1, 2023.

The BASIX tool checks the following listed elements of a proposed residential building design against sustainability targets:

  • Energy: The assessor measures the energy consumption by fixed appliances used in a home, such as hot water systems, cooktops, ceiling fans, air conditioners, lighting, and more.
  • Thermal comfort load: It can be defined as the energy required to cool or heat the house to maintain a comfortable temperature. The BASIX assessor puts a cap on thermal comfort loads, considering the local climate and building’s size, form, orientation, glazing, insulation, ventilation, etc.
  • Water: Water usage of taps, shower heads, toilets, or other fixtures and fittings provides a score for water-saving measures, like rainwater tanks.

After assessing these elements, the assessor provides the homeowner with the BASIX Certificate as formal evidence that the residential project complies with the required energy, thermal comfort, and water targets.

How the Changes in BASIX Certificate Requirement Will Affect Your Home Build?

The BASIX scheme covers how the home is designed and what building materials, fixtures and fittings are used.

The changes in the BASIX scheme will present multiple challenges for new home builders, especially when it’s about achieving a 7-star NatHERS rating for home design’s thermal performance.

Architects and constructors will have to carefully customise the design and elevation of homes and design them for specific site orientation to achieve 7-star compliance while meeting the homeowner’s objectives of natural light and views.

Moreover, compliance in most cases will require builders to upgrade glazing or reduction in windows significantly.

Aside from the changes to BASIX standards, the push towards electrification of newly built homes is another vital change. The updated BASIX standard will require homeowners to use electric cooktops and heat pumps for hot water supply.

Although homeowners can still use gas cooktops and water heaters, they will have to offset them with a modest solar system. Moreover, assessors will need to submit the BASIX report on the embodied carbon emission of the home.

Here listed are necessary features to include in your home to comply with the 7-star rating under the updated BASIX scheme. These features will help reduce a house’s energy consumption and enhance thermal performance:


  • Wall wrap: With wall wrap, insulation will work more efficiently while protecting a building structure from harsh weather conditions.
  • Anti-condensation blanket: Add a foil-faced insulation blanket specifically designed for temperature and noise control in your home.
  • Sarking: It is a pliable membrane that can be placed under your roof tiles, like a protective second layer. Installing it will help insulation work more efficiently and protect the home’s contents from extreme climatic conditions, condensation, and bushfire ember attacks.
  • External wall insulation R2.5: The R-value measures how well an insulation layer can resist heat. Adding this level of insulation can offer thermal benefits.
  • Ceiling insulation R6: The layer of R6 ceiling insulation in the home can potentially offer savings between 20% and 40%.
  • Windows: Installing windows in a home accounts for about 50% heat loss and 90% heat gain. The new BASIX standards will require specific types of glazing for homes built in different zones to improve thermal performance and allow buildings to capture more natural light. You can connect with reputed BASIX consultants to get tailored solutions for your new residential project.
  • Rainwater tank: To use water sustainably, it’s recommended to have a rainwater tank of 3000 litres for single and double-storey homes and a 4000-litre tank for acreage.
  • Hot water heating: Homeowners can ensure lower greenhouse gas emissions and running costs by installing a Continuous Flow Natural Gas heater.
  • Ceiling fans: Equipping every room in a home with ceiling fans will increase natural ventilation and significantly reduce the need for further cooling.
  • 3KW rooftop solar grid: It’s the crucial building element that can boost a house’s access to sustainable energy.

How the Changes in BASIX will Affect Project Cost?

With the changes in the BASIX certificate requirements, you can expect additional costs because of building components required to comply with new energy efficiency and thermal performance standards.

These building components include but are not limited to the above-listed items. The project cost will vary depending on home design, climate zone, proximity to other buildings, neighbouring shedding, and other factors.

However, the initial costs can be covered by the increased economic value of your project in the market due to enhanced sustainability and healthier living standards.

To Wrap Up It All

With the changes in the BASIX scheme coming into effect from October 1, 2023, the builders, architects, and assessors need to update themselves with the same.

Only the updated builders and architects can help homeowners build energy-efficient new homes in New South Wales.

Moreover, professional BASIX Consultants can recommend developers and building designers as to what building elements they should add to the home design for increased BASIX ratings.

Leave a Comment

DISCLOSURE: Some posts may have affiliate links, which means that if you click on the links and make a purchase, we get a commission. Note: That doesn’t affect our recommendations in any way. We are committed to giving you the best.