What is Green Star Rating?

Green Star Rating FAQ's

• What is Green Star Rating?

  A Green Star Rating is an assessment tool that demonstrates how successfully a project has met the credits and requirements of the Green Star standards. More specifically, a Green Star Homes rating is split into two (2) stages:

  1. Green Star Designed: An initial assessment conducted with the Green Building Council of Australia (GBCA) which ensures initial designs meet Green Star Homes Requirements. If successful, your project will be awarded 'Green Star Designed'.
  2. Green Star Certification: This stage can only be conducted following the successful completion of the Green Star Designed stage. Green Star Certification is a formal process involving a third party, who will provide a rating based on the project's submission and the rating requirements of Green Star Homes. This is the only certification that proves that your project has successfully met the requirements of Green Star Homes and is therefore Positive, Healthy and Resilient.

• What is a Green Star Home?

  The Green Star Home Assessment and Rating Scheme was released in 2021 with the intention of setting a minimum standard for the sustainability of homes across Austraila. As such, a Green Star Home is designed to be a comfortable, healthy and cost-effective home that has a reduced impact on the health of occupants and the environment. A Green Star Home is designed to meet the standards set by the Green Building Council of Australia (GBCA) and is to be independently assessed against the three categories of Positive, Healthy and Resilient.

• What is the Green Star Home Standard?

  The Green Star Home Standard is a document that outlines the credits and requirements to achieve Green Star Designed and Green Star Certification. These standards are set by the Green Building Council of Australia (GBCA) and are to be independently assessed against the three categories of Positive, Healthy and Resilient.

   

  Our team at Certified Energy is highly specialized and skilled to complete these assessments and provide you with a Green Star Home Rating. For any questions or to get your job started with us, you can contact us on 1300 443 674 or click here.

• Why should I get Green Star Home Certified?

  Green Star Home Certification can:

  • Maximise the Health, Positivity and Resilience of your home
  • Give your home a unique point of difference in the housing market
  • Provide a clear set of standards to ensure your home is safe for both you and the environment
  • Demonstrate your commitment to sustainability and doing the right thing
  • Ensure your home is in line with contemporary and leading sustainability practices.

   

  In addition, a Green Star Home possesses the following benefits:

  

  If these reasons aren't enough, get in touch with us today to discuss your project and the benefits of Green Star Certification further.

• What are the Green Star Home Categories?

  There are three (3) categories which must have minimum requirements met to achieve Green Star Home Certification.

  1. Positive: Fully electric, draught sealed, efficient and powered by renewables.
     This encapsulates:
     - Thermal Performance
     - Window System
     - Airtightness 
     - Hot Water
     - Energy Efficient Appliances
     - Renewable Energy
     - Home User Guide
     
     
  2. Healthy: Ventilated, comfortable and with products that are better for you.
     This encapsulates:
     - Air Quality
     - Moisture Management
     - Light Quality
     - Material Toxicity
     
     
  3. Resilient: Water efficient and climate change ready.
     This encapsulates:
     - Water Use
     - Heat Resilience
     - Resilience Essentials

• What are ways to avoid double glazing?

  One of our most frequent requests from our clients is to reduce or remove the requirements of double glazing on their projects. Double Glazing can cost up to twice the amount of single glazing and on some projects it can tip the feasibility scales. Every year it seems the ever improving Energy Efficiency - Section J of the National Construction Code and the National Thermal Comfort (NatHERS) regulations are making it increasingly difficult to avoid specifying double glazing. However, at Certified Energy we have 5 tried and true tips that will go a long way to avoid specifying double glazing on your next project.

   

  1. Keep your Glass to Floor ratios down

  Perhaps the only, yet most important variable that we as Thermal Comfort Assessors don't have direct control over on this list is the Glass to Floor Ratio on a project. A Glass to Floor (GtF) ratio is the total glazed area added together on a project divided by the total floor area of a project to give an overall percentage. Coming from an Architectural background I can understand that this dynamic glass to floor relationship on a project can be at the heart of the overall aesthetic appeal, but if it is not taken into account at the early design phases of a project an overly high Glass to Floor Ratio can have devastating effects to the heat loss of your project, as heat loss is generally twice high in glazed sections of your project compared to insulated walls.

  From our experience and as a general rule of thumb, here are our recommended glazing types that are required based on a projects overall % of glass to floor area (applying to the majority of climate zones).

  • 0 - 25%     Requires Single Glazed Clear Glass
  • 25 - 35%   Requires Single Low -e Glazed Clear Glass
  • 35 - 45%   Requires Double Glazed Clear Glass.
  • >45%        Requires Double Glazed with Low -e Clear Glass which generally requires improved aluminium Argon gas filled frames.

  To further illustrate this point, a typical project home will have approximately 18-20% of glass to floor ratio, this can be compared to an Architecturally designed 2 story 'glass box' type house which we previously assessed that had an unusually high glass to floor ratio of over 55%.

   

  2. Use higher performing wall insulation

  Standard bulk wall insulation with reflective foil to fit within a 90mm frame for typical Brick Veneer construction has a highest R value of R2.5. It is possible however to use rigid foam insulation which comes in thickness of up to 40mm which can then provide a total Rt of up to R5.6 for Brick Veneer construction. Providing two layers of this rigid insulation product in the 90mm brick veneer frame effectively doubles the insulation in the external walls. This method is often much more cost effective than having to specify double glazing on a project.

   

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