Energy Performance Certificates applied to Historic Buildings: A Clash Between Method and Context

Many of the built environment’s sustainability and carbon reduction agendas are geared toward 2050. Yet, it is estimated that up to 80% of the buildings that will exist in 2050 have in fact, already been built. It is therefore argued that if any of the climate change goals are to be met, we need to radically reduce the carbon emissions from our existing building stock. Energy performance certificates (EPCs) are vital in the UK government’s strategy around climate change and energy use reduction within the built environment. Worryingly, an increasing amount of literature is now questioning the reliability of the data from EPCs and if it is fit for purpose. The research will focus on the group of buildings most impacted by the use of EPCs, the historic (pre-1919) housing stock. Alarmingly, some of the most effective measures of reducing carbon emissions and energy usage in historic houses have only a small impact on the EPC score a building receives. The paper aims to understand the key issues that cause a performance gap and how many historic dwellings perform much better than their EPC might suggest. The research draws upon existing literature before mobilising primary case studies and supportive datasets. Analysis and subsequent findings challenge the current rhetoric, whereby many small benign changes can have a considerable effect on reducing carbon and energy usage, and that many of the recommendations that owners of historic buildings receive on the EPC report are either, at best, far more financially costly and, at worst, extremely damaging to the historic fabric and the heritage of the dwelling. The existing EPC framework is fundamentally ineffective in accurately predicting energy and carbon usage in historic dwellings.