What is a BASIX Certificate and When Should it be Included?

A BASIX certificate is a legal requirement for most residential developments in New South Wales.

It confirms that your project meets energy, water and thermal efficiency standards under NSW planning policy.

At Town Planning Sydney, we help you secure and integrate your BASIX Certificate correctly, so your development application or CDC is not delayed.

Here’s what you need to know.

1. BASIX stands for Building Sustainability Index

It’s an online tool that measures the sustainability performance of new homes, major renovations and multi-dwelling projects.

Once your design meets the required targets, the tool generates a BASIX Certificate, which must be included in your DA or CDC submission.

2. It is mandatory for most new residential buildings

If your project involves a new house, dual occupancy, multi-dwelling housing or renovations over $50,000, you must include a BASIX Certificate.

This applies whether you're applying through the development application pathway or via Complying Development.

We check whether your proposal triggers this requirement before we finalise your plans.

3. It must be included before lodging your DA or CDC

A BASIX Certificate must be attached to your submission when you apply for DA approval or council approval.

If it’s missing or inconsistent with your plans, your application may be rejected or delayed. Our team ensures your BASIX Certificate aligns exactly with your architectural drawings.

4. It includes commitments you must follow

The certificate lists all sustainability commitments for your build. These may include rainwater tanks, insulation levels, solar hot water, window types and native landscaping.

We include all these features in your site plan, floor plan and elevation drawings to avoid inconsistencies.

5. Certifiers and councils will enforce it

Once issued, the BASIX Certificate becomes a binding part of your development application.

Private certifiers and local councils will check that the commitments are actually installed or built.

In Waverley, we helped a client update their BASIX after changing roof materials to maintain compliance before construction.

6. BASIX can affect design choices and construction costs

Because it sets sustainability benchmarks, BASIX can influence roof colours, window sizes and materials.

Our planning consultants work with your designer to meet these targets while managing your build budget and timeframes.

7. BASIX updates regularly, use the latest version

The NSW Government updates BASIX targets from time to time, including stricter water and energy standards.

We ensure that your Certificate is current and reflects the latest performance rules at the time of lodgement.

At Town Planning Sydney, we don’t just tick the box, we provide strategic planning advice to make sure your BASIX Certificate works with your full submission package and leads to smooth DA approval.