10 min read

BASIX for Swimming Pools and Spas in NSW

By Team CE on Jun 6, 2026, 3:05:57 PM

A swimming pool or spa in NSW may need a BASIX Certificate when it forms part of a residential project or when the pool or spa reaches the relevant volume threshold. BASIX is not only about the dwelling itself. It can also assess the water and energy impact of pools and spas, including their size, heating, pump systems, covers, shading and water top-up arrangements.

Topics: BASIX NatHERS 7 Star Homes BASIX Certificates NatHERS Existing Homes

9 min read

BASIX for Granny Flats and Secondary Dwellings

By Team CE on Jun 6, 2026, 2:54:20 PM

BASIX for Granny Flats and Secondary Dwellings

A granny flat or secondary dwelling in NSW will often need a BASIX Certificate as part of the residential approval process. This is because BASIX applies to NSW residential development and assesses water, energy use and thermal performance. For a secondary dwelling, the BASIX pathway depends on the type of project, how the dwelling is created and whether the approval is being lodged as a Development Application or Complying Development Certificate.

Topics: BASIX NatHERS 7 Star Homes BASIX Certificates NatHERS Existing Homes

10 min read

BASIX DA vs CDC: What Changes?

By Team CE on Jun 6, 2026, 2:48:37 PM

BASIX DA vs CDC: What Changes?

BASIX can be required whether a residential project in NSW is submitted through a Development Application or a Complying Development Certificate pathway. The certificate itself still addresses water, energy use and thermal performance, but the approval pathway changes who reviews the application, how the documents are lodged and how quickly the project may need to be ready for assessment.

Topics: BASIX NatHERS 7 Star Homes BASIX Certificates NatHERS Existing Homes

9 min read

Can a BASIX Certificate Be Amended?

By Team CE on Jun 6, 2026, 2:31:20 PM

Can a BASIX Certificate Be Amended?

Yes, a BASIX Certificate may need to be amended, revised or replaced if the project changes after the original certificate has been prepared. This can happen when the design changes, the glazing changes, the insulation strategy changes, a hot water system is updated, a rainwater tank commitment is altered or the plans no longer match the certificate commitments.

Topics: BASIX NatHERS 7 Star Homes BASIX Certificates NatHERS Existing Homes

27 min read

What Happens If My Project Fails BASIX? | Certified Energy

By Team CE on Jun 6, 2026, 2:15:06 PM

NSW Residential Compliance Guide

A project that does not initially meet its applicable BASIX requirements is not automatically rejected, but a BASIX Certificate cannot yet be finalised for lodgement.

The phrase failing BASIX is commonly used when a residential assessment has not yet achieved the water, energy or thermal performance requirements applying to the project. It may also refer more broadly to an incomplete assessment that cannot yet generate a Certificate.

In most cases, this is a design and documentation stage rather than a final refusal. The assessor reviews the result, identifies the part of the assessment requiring attention and determines whether the issue comes from incorrect information, an unresolved specification or a genuine performance shortfall.

This guide explains what happens next. For a broader explanation of BASIX targets, documentation and the NSW submission pathway, visit the BASIX Knowledge Hub.

Topics: BASIX Residential Compliance

9 min read

What Documents Do You Need for a BASIX Certificate?

By Team CE on Jun 6, 2026, 11:09:59 AM

What Documents Do You Need for a BASIX Certificate?

To prepare a BASIX Certificate in NSW, an assessor needs enough project information to understand the design, building fabric, water commitments, energy systems and thermal performance pathway. The exact documents required depend on the project type, but most BASIX assessments begin with the architectural drawings and then move into the details that affect water, energy and thermal comfort compliance.

Topics: BASIX NatHERS 7 Star Homes BASIX Certificates NatHERS Existing Homes

17 min read

BASIX Certificate Cost NSW: Fees and Pricing Guide

By Team CE on Jun 6, 2026, 11:04:24 AM

How Much Does a BASIX Certificate Cost in NSW?

The cost of a BASIX Certificate in New South Wales has two separate components: the official NSW Planning Portal fee and the professional fee for preparing the assessment.

The official portal fee is currently $5 per BASIX Certificate application. The professional assessment fee is separate and depends on the residential project type, number of dwellings, thermal-performance pathway, quality of the plans and level of design coordination required.

A straightforward alteration may require a different scope from a custom home, dual occupancy or townhouse development. Where NatHERS thermal simulation is required, the modelling and assessor documentation also form part of the professional scope rather than the $5 portal charge.

Topics: BASIX Residential Compliance

25 min read

Design Optimisation and BASIX in NSW | Certified Energy

By Team CE on May 25, 2026, 8:00:15 PM

NSW Residential Compliance Guide

BASIX design optimisation is the process of identifying which project inputs are limiting compliance and refining them without making unnecessary changes to the wider residential design.

A project that does not initially achieve its required BASIX outcome does not necessarily need a complete redesign. In many cases, the result can be improved through a targeted review of the assumptions, specifications or design elements affecting the relevant assessment component.

The important first step is diagnosis. Water, energy and thermal comfort respond to different inputs, and a change that improves one part of the assessment may have little effect on another. Repeatedly upgrading unrelated products can increase project cost without resolving the actual constraint.

This guide focuses specifically on how BASIX outcomes can be refined through a structured design process. For the wider assessment, certification and NSW submission pathway, visit the BASIX Knowledge Hub.

Topics: BASIX Residential Compliance

21 min read

BASIX and Airtightness in NSW | Certified Energy

By Team CE on May 25, 2026, 2:23:00 PM

NSW Residential Envelope Guide

Airtightness can influence real-world comfort and energy use, but its relationship with BASIX is more specific than simply describing a home as sealed or draught-free.

Uncontrolled air leakage can allow conditioned air to escape and external air to enter through gaps, penetrations and construction junctions. This can create draughts, reduce temperature stability and weaken the practical benefit of insulation and efficient heating or cooling systems.

Within a BASIX thermal comfort assessment using NatHERS software, air movement is represented through standardised modelling assumptions and inputs for relevant openings and penetrations. The assessment does not ordinarily measure the completed home’s actual whole-building leakage rate.

This guide explains that distinction. For the wider BASIX targets, documentation and NSW submission pathway, visit the BASIX Knowledge Hub.

Topics: BASIX Residential Compliance

33 min read

BASIX Water Efficiency NSW: Targets and Requirements

By Team CE on May 25, 2026, 2:16:33 PM

The BASIX Water section assesses how a proposed residential development will reduce its demand for potable water compared with the NSW residential benchmark.

The result is influenced by water-efficient fixtures, landscape areas, low-water-use planting, rainwater or other alternative water sources, pools and spas, and any central systems or common areas associated with the development.

A passing water result is not produced by one universal requirement. The appropriate combination depends on the project location, dwelling type, landscape demand, water systems and commitments selected within the assessment.