Frequestly asked questions

What is a home energy rating?

A home energy rating is an estimated calculation into a homes potential energy usage, which will determine the amount of heating and cooling required to make its occupants comfortable. It produces a star rating dependant on the amount of heating and cooling loads which will be required, from 0 to 10 stars.

What information do I need to supply for an energy rating to be complete?

The information we require to complete a full and comprehensive energy report are the following final working drawings in a PDF format:
Site Plan, Floor Plan, Elevations, Sections, Lighting layout and window schedule (including sizes of the existing windows).

Why and when do you need an energy rating?

You will need a residential home energy rating if you are building a new home or undertaking major renovations. As it is a minimum standard which has been set to outline each state and territory minimum requirements based on the National Construction Code. You will be required to submit an energy rating report completed by an Accredited Assessor to either your shire/council or building surveyor in order to achieve a building permit.

How many stars must my residence achieve?

A minimum of 6 Stars must be achieved for all new stand alone residences. With apartments having also to achieve an average rating of 6 Stars and with no apartment achieving less than 5 Star.

What is the cost of the home energy rating?

The cost will vary depending on the complexity of the proposed residence or extension. Our prices are inclusive of all the costings which go into being an accredited NatHERS assessor, this also includes the cost of producing the NatHERS FirstRate5 certificate.

How long does the home energy rating take?

We can deliver you a extremely fast turnaround of 2 working days for simple and straight forward single and double storey, for larger multi-unit developments a large turnaround of 5 business days maybe required. An approximate timeframe will be given at quotation stage.

In which Australian state is a home energy rating required?

All states and territory require energy rating certificate. Although different rules and regulations do apply.

Who is allowed to produce a home energy rating?

In most states building surveyors and council/shires will only accept an energy efficient certificate produced by an accredited assessor.

What is FirstRate5?

FirstRate5 is the home energy rating software we use to generate 6 Star energy ratings. It is an interactive tool with a graphic user interface that enables designers and thermal performance assessors to generate energy ratings. The software uses a calculation engine to estimate the annual heating and cooling energy that is required to make the home thermally comfortable.

How does the software rate the energy efficiency of the home?

The software used is based on scientific research by the CSIRO. It estimates how much energy your home will require for heating and cooling. It bases these calculations on the layout of the home, its construction materials roof, walls, windows and floor coverings. Also calculated is the locations climate, orientation of it window in relationship to the the suns path and local breezes.

What are the elements that will have an affect on rating results?

The elements which are imputed into the software are as follows: Climate zone, Building orientation, proximity to neighbouring houses, Wall type and insulation, Roof type and Roof/Ceiling insulation, Floor type and insulation, Ceiling penetrations (downlights and ceiling exhaust fans), Floor type and insulation, Window glazing type and frames, Internal floor coverings and External wall and roof colours.

What is ABSA?

ABSA is the Assessor Accrediting Organisation. Their roll is to offer Assessors support, ensure quality assurance of assessments, ensure the Assessor for fills their requirements of continued professional learning and maintain procedures all Assessor must adhere to.

What is NatHERS?

Is the Nationwide House Energy Rating Scheme (NatHERS). NatHERS have designed a star rating system form 0 to 10 stars, which is based upon the energy efficiency of the residential home base on its design. So the more energy efficient and the higher your star rating the more money you can potentially save on your energy bills.

Do I need a home energy rating for renovation or extension?

Yes, any renovation and or extension will require an energy rating. Work that represents over 50% of the original home will require a 6 Star rating. Any work which represents less than 50% of the original dwelling will only then require the new area to achieve a 6 Star rating. Your own specific requirements will be outlined at quotation stage.

What do the stars indicate?

Zero star rating basically means that the residence does practically nothing to reduce the comfort of hot and cold weather.

Six star rating basically indicates a good but not an outstanding performance. Ten star rating is a home with excellent thermal comfort and may not require any mechanical heating or cooling.

How hard is it to achieve a 6 star home energy rating?

In some instances a 6 star rating can be very easily achieved with very minimal if any upgrades. However a few factors can come into play that may help or hinder your rating, namely these factors are mainly due to the its design and or orientation.

What if my proposed residence does not achieve a 6 Star rating?

If in case your proposed residence does not achieve a 6 Star rating, then we will give you some sound advice on a range of changes which can be made to achieve a 6 Star rating.

What steps can be taken to achieve a higher rating?

Firstly the design of your house and its orientation should be such that it takes advantage of the passive heating and cooling available in the particular climate zone.

Will achieving a 6 star energy rating increase my construction cost significantly?

In some cases yes, but with a well thought out and designed house there may no additional or minimal costs. It may well be a good idea that you brief your Designer/Architect that they consider the energy efficiency of the proposed design in its early stages, if cost is an issue.

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Phone: 0497 911 633

Email: mark@buildmark.com.au