Insulation is a very important consideration when it comes to building a home in Australia. Most residential builders are familiar with the term ‘R-Value’ typically associated with insulation. For the benefit of owner-builders, Foamex Group explains the meaning of R-Value, how to determine the R-Value of an insulation material, and also how to find out the most appropriate R-Value for your climate.
What is ‘R-Value’?
R-Value refers to a material’s thermal resistance (ability to block heat), while U-Value relates to thermal transmittance (ability to transmit heat). Materials with a high R-Value will have a low U-Value, and vice versa. R-Values are used in the building and construction industry, while other thermal resistance measures are used in industries such as textiles.
How is an R-Value established?
There is a formula to determine the R-Value of a material. The formula measures the ratio of temperature difference between the two sides of the same material, along with the amount of heat that can pass through it. When an R-Value is recorded for an insulation material, it is based on that material alone without any other additional layer of insulation, or method of installation taken into consideration.
Determining the right R-Value
R-Values largely depend on the type of climate in the region where the house is located. The Building Code of Australia (BCA) can be referred to find the minimum values for each climate type. Find out what the minimum value is for your area, and also refer any requirements specified by your state or territory.
Up and Down values
In addition to the various R-Values, you will also need to consider ‘up’ and ‘down’ values that indicate the direction of heat transfer. The ‘up’ measures the flow of heat rising up through the insulation, while the ‘down’ measures the amount of heat passing through the insulation. These are also known as the summer and winter values, respectively.
When it comes to choosing the right insulation with the correct R-Value for your home or project, speak with one of Foamex Group’s state sales representatives who will be able to advise you on the best foam insulation for your build.