Demonstrating thermal performance: The role and challenges of testing methodologies

Abstract

The UK's commitment to reduce CO2 emissions by 80 per cent by 2050 presents the construction industry with an extremely difficult challenge. To produce the highly energy-efficient new buildings and adequately retrofit the 20 million existing ones we must start to use all the tools at our disposal. Worryingly, it is now apparent that a significant gap between the as-designed thermal performance of buildings and the actual performance already exists. This paper puts forward the case that a significant contributor to that gap is the regulatory regime that has been put in place, which allows the U-values of all the building components and structures to be calculated — never verified by measurement. A list of the main measurement and calculation standards that are available is then given with a brief description of their possible place in a rigorous system for ensuring that building designs are based on accurate, validated thermal performance values for the structures from which the energy performance is calculated.