Alububble radiant barrier insulation, manufactured by Africa Thermal Insulations (ATI) has been used for many years mainly in industrial applications. Over recent years it has gained popularity in domestic applications as well. Although it is clear that the product works, there have been no recognised test methods that measure the difference radiant barriers make to internal temperatures when installed. ATI therefore decided to conduct a test case study using thermal imaging.
First, in an uninsulated house, it recorded thermal images and temperatures at different points outside and inside the building. These temperatures showed the heat flow into the house. A retrofit installation of Alububble was then completed in the house and thermal images and temperatures were recorded again.
The outside temperature on both days was recorded at 30°C but the difference in the internal temperature, once the Alububble radiant barrier had been installed, was notable. The diagram illustrates the temperature readings on both the insulated and uninsulated house.The insulated house shows a difference of 3°C in the internal temperature. While this does not seem like a lot, to reduce the inside temperature from 27°C to 24°C is great as it brings the internal temperature within the range of accepted human comfort levels.
However, ATI points out that, on its own, radiant barrier insulation does not meet the resistance value recommended for domestic homes in the SANS 204 Energy Efficiency Standard. A minimum of 100mm bulk insulation in the ceiling would be needed to achieve a system R-value of 3.7, which is the recommended requirement in terms of SANS 204 for the Gauteng area.
ATI believes that every home should be insulated with both radiant barrier insulation, which controls heat flow into the building during the summer months, and bulk insulation which is particularly effective in controlling heat flow out of the building during the winter months. The two products working hand in hand with each other will provide the required level of interior thermal comfort through summer and winter.