Results variability in accredited building energy performance compliance demonstration software in the UK: an inter-model comparative study

In the context of performance-based building regulations, the benefits provided by building energy performance prediction tools in facilitating the exploration of innovative approaches to achieving performance requirements has been recognized. In accordance with the Directive on Energy Performance of Buildings (EPBD), the UK has introduced a methodology that allows the use of accredited third-party software for demonstrating compliance with energy performance criteria outlined in the relevant technical guidance for the non-domestic sector. This study investigates the issue of predictive inconsistencies between accredited tools available at the time of writing and presents the final results of an inter-model comparative analysis that examines the extent of variability in key compliance outputs. An overview of tool applicability limitations and issues associated with results variability are presented. Implications concerning the credibility of the methodology and recommendations to address current shortcomings are noted.