BCA Regulations

6 star energy rating

From 1 May 2011, all new homes, renovations and additions will be required to meet a minimum 6 star energy rating.

I'm not building a new home!

If you are making alterations to 50% or more of the volume of the existing dwelling, then the whole dwelling will need to achieve a 6 star energy rating. If the altered area is less than 50% of the volume of the existing dwelling, then only that part of the dwelling is required to achieve a 6 star energy rating. The building surveyor has some discretion in certain circumstances. For further information, contact the Building Commission.

Conclusion

From 1 May 2011, all new homes, renovations and additions will be required to meet a minimum 6 star energy rating.

General

In 2010, the Building Code of Australia (BCA) introduced significant changes to what was allowed in terms of energy consumption from lighting per square metre in your home. In particular, the Code looks at the amount of insulation in a ceiling and the influence it has on the installation of downlights; the maximum power capacity of lights, fans, pumps and other air-conditioning equipment; energy monitoring and metering facilities; and restrictions on use of electric heaters. Essentially all new homes and apartments need to have the equivalent of a six-star energy efficiency rating.

What if my dwelling doesn't reach 6 stars?

If the energy rating comes back short of 6 stars, changes will be required. This has the potential to increase the cost to build, especially if the energy rating hasn?t been considered at the beginning of the design. Correct orientation and building materials could mean the insulation required for the home isn?t as highly rated as it may be required if the building achieves a lower energy rating.

Regulations

The main thing you need to be aware of is that as of May 2011, you will only be allowed 5W of lighting power per square metre, as opposed to the 25W per square metre of yesteryear. Concessions to this rule exist if certain lighting controls are used, and vary depending on the particular setup and hardware.

How is it calculated?

An energy rating can only be established by an accredited energy rater. To perform their assessment they will require the lighting plans, site plans, floor plans, elevations, window schedule and the construction materials for the dwelling (eg the type of cladding, what rating of insulation, roof material to be used, etc). The energy rater will feed this information into the energy rating program to calculate the star performance of the dwelling. If the dwelling achieves less than 6 stars, the energy rater will suggest changes to ensure a 6 star rating is achieved. This could be double glazed windows or insulation of a higher rating.

What is an energy rating?

An energy rating for your home is a calculation of the thermal performance of the dwelling, or simply put, the heating and cooling requirements to maintain a comfortable temperature. The lower the rating, the more reliant on mechanical heating and cooling devices the dwelling?s occupants will be to establish and maintain a comfortable temperature. A lower rating will also mean higher energy bills.

What does this mean for my project?

As of 1 May, a building surveyor will need to ensure that a dwelling (or in certain circumstances the addition only) achieves a minimum 6 star energy rating to grant a building permit. It is important that your designer is thinking of the energy rating at the beginning of the design ? orientation, size and placement of windows and shading are just a few of the elements that need to be considered.

5W per square metre

The main thing you need to be aware of is that as of May 2011, you will only be allowed 5W of lighting power per square metre, as opposed to the 25W per square metre of yesteryear. Concessions to this rule exist if certain lighting controls are used, and vary depending on the particular setup and hardware. If you are planning or building a home you should ensure that your lighting designer and electrician are aware of these changes, otherwise you could be in for long delays and increased cost to fix it. Houses that don't meet these stringent new requirements may well fail their final inspections.