The amount of insulation required in buildings would differ from location to location in Australia, due to the country’s differing climate conditions.

In Brisbane the recommended insulation R-Value is 1.5-2.5 for the ceiling or roof, while the R-Value would be 1.5-3.0.

The R-Value is a thermal performance rating system that aims to help builders and insulators alike determine the right insulation product for their area and building project.

All insulation materials are rated under the R-Value for their performance in resisting heat flows, which provides cooler areas in summer or warmer in winter. The higher the product’s R-Value is, the greater the insulating effect. If two products hold the same R-Value their insulation performance would be the same, regardless of their manufacturing difference.

There is also different ways of reading the R-Value rating system depending on each type of insulation products being used. Added R-Value is the rating for the insulating material itself while Overall R-Value adds together the total resistance of the building element

The R-value of bulk insulation is provided by the manufacturer under one rating. This rating is measured according to the combination of thickness and density within the insulation product. Each thickness and density would hold their own R-Value rating. However it is the total R-Value of the product that is usually shown.

The R-value of reflective insulation is measured on the product’s direction of heat flow. 

  • Up R-Value refers to materials with resistance to upward heat flows (also known as winter R-values).
  • Down R-Value refers to materials with resistance to downward heat flows (also known as summer R-Values).
In order to determine the right R-value insulation products for a building or construction project, it is best to contact the area’s local government or businesses with insulation installation expertises.

For more information on insulation and the R-value thermal resistance rating systems, contact Australia’s Department of Climate Change and Energy Efficiency.