home insulation factsheet

Over time, insulation material in your home deteriorates and becomes less effective in cooling in summer and warming in winter. Older insulation material will need to be upgraded or replaced. It is estimated that good insulation lasts for up to 20 years.

When correctly installed, insulation will help save money on power bills as less energy is used in home heating and cooling.

Installing insulation or upgrading the insulation in an average house may cost anywhere from $1200 upwards, however it will make your home a more pleasant environment to live in and ultimately save you money on heating and cooling costs.

What is the standard for insulation?

The benefit of insulation is measured by its Thermal Resistance or ‘R-Value’. Under the building code of Australia, all new homes in Perth are required to have an insulation with a minimum value of 3.0 for all ceilings and bulkheads and 0-1.5 for the walls, depending on type. Homeowners are encouraged to have a retrofit of new insulation to meet these standards.

What to remember when buying insulation:

1. Choose insulation according to the R-Value
Make sure you choose insulation with the higher R-Value. Different insulation materials with the same R-Value will perform just as effectively. For example batts with an R-3.0 will perform exactly the same as loose fill with an R-3.0.

2. Get multiple quotes from suppliers

It is a good idea to get multiple quotes to ensure you are getting good value. It is important to also ask for a certification value for the type of insulation you are interested in. The insulation should be certified in writing by the supplier as being to Australian Standard AS3999.

3. Keep in mind the “hot-box” syndrome
Shade east and west-facing windows with adjustable awnings, deciduous trees or a pergola and the north with eaves to block the summer sun. Unshaded windows build up heat inside the home and the insulation keeps the heat inside, resulting in an oven effect. For more information see our fact sheet on window coverings.

4. Fire protection
It is important to ensure that your chosen insulation materials are either non-combustible or fire-proof.

Some tips on the different types of insulation:
•     Blown-in products settle over time, so you will need to measure thickness every 5 years to find out whether an upgrade is needed.
•     Batts are bonded strongly so will stay thick for a longer time, and are easy to install. Also if work needs to be done in the ceiling later on, a batt can easily be removed and replaced in its original position.