All window manufacturers in Australia are required under the Building Code of Australia to produce windows and doors that meet certain requirements. These requirements are detailed in technical documents known as Standards which are developed in consultation with industry and government agencies.
Why are Standards important?
Standards ensure products and construction processes meet certain quality and structural integrity requirements. Globalisation also means that materials can now originate from many parts of the world. Mandating minimum safety requirements for materials and construction methods ensures they are of a certain quality and will withstand Australian conditions.
Window and glass standards
All windows and glass used in Australian homes must comply with the following Standards:
- AS2047 Windows in buildings – Selection and installation
- AS1288 Glass in buildings – Selection and installation
- AS4420.2 Deflection Test – positive and negative wind pressures are applied to the face of the window to test the maximum deflection under wind load.
- AS4420.3 Operating Force Test – verifies that an opening sash is capable of opening and closing without undue effort.
- AS4220.4 Air Infiltration Test – air leakage of a window is tested to ensure energy and acoustic efficiency.
- AS4420.5 Water Penetration Resistance Test – ensures no water leaks through the window into the building.
- AS4420.6 Ultimate Strength Test – negative and positive wind pressures of at least 1.5 times the specified wind pressure are applied to the window to ensure it does not fail in unusual wind conditions.
Question: How do I know that the builder has installed windows and doors in my home that comply with the Building Code of Australia?
Answer: All windows and doors for homes must have a performance label which confirms they are certified to comply with Australian Standard AS2047.
- Windows purchased from accredited AWA members come with a Certificate of Compliance providing a minimum 7 year warranty.
Energy Efficiency Legislation
Across Australia, the energy efficiency bar is being lifted with the rise from a 5 to 6-star energy rating mandatory for all new residential buildings. The requirements of the 2010 Building Code of Australia are designed to improve the performance of Australia’s greenhouse gas emissions. While the commencement date of this legislation differs from state to state (Victoria, Queensland and the ACT have already introduced the code), at some point in the near future all Australian homes will need to meet this minimum level of energy efficiency. Energy ratings apply to the whole building – not just individual elements or materials.
An energy efficiency star is a measure of how much energy ‘leaks’ through the skin of a building over the course of a year within a given climate. It is an expression of how much artificial heating and cooling energy will be required to keep the inside temperature within a standard ‘comfortable range.’
- 0 stars means the home offers no barrier to the external temperatures
- 10 stars means that the home requires no additional heating or cooling energy
The achievability of star ratings is largely dependent on the climate experienced by the home. For example, the amount of energy lost from a 6-star rated home in Brisbane will be different to (less than) that for a home in Canberra. Generally speaking, compared to other materials used in the building, windows are poor heat insulators and let a lot of radiant heat from the sun into a home. Therefore windows have a big impact on the star rating that can be achieved by a home.
Requirements for existing homes
New energy efficient requirements are also set to affect the sale or lease of existing homes across Australia. Mandatory disclosure requires homeowners to disclose a home’s energy, water and greenhouse performance to prospective buyers and tenants so they can better judge the property’s value. It is expected the measure will be phased in by May 2011, starting with disclosure of energy efficiency. Refer to the government’s National Strategy on Energy Efficiency for more information.