Despite world-class products being manufactured in Australia, cool roof technology is, as yet, greatly under-utilised both locally and internationally.
Large-footprint buildings provide a significant opportunity for market penetration of local cool roof technologies, which will open up the cool roof market more generally; as long as the current barrier of lack of rigorous evidence and design information can be overcome.
Building energy modelling software packages, for example, greatly under-predict the benefit of cool roofs on large-footprint buildings because they do not account for the significant negative impact of the ‘heat-bubble’ that develops above a normal (non-reflective) roof in summer. The elevated temperatures in such heat-bubbles (or building-scale heat islands, BSHIs) significantly reduce the performance of roof-mounted cooling plant. The removal of this detrimental impact through use of cool roof products is likely to result in an even greater decrease in building energy use than through the ‘passive’ impact of the cool roof reducing heat flow through the roof structure into the building.
The project will deliver:
a) a comprehensive set of cool roof design and cost-benefit calculation resources, focussed on typical large-footprint Australian buildings; and
b) a rigorous experimental and simulation evidence-base of the impact of cool roof products on building thermal performance and the characteristics of the building-scale heat island above large-footprint buildings.