Meta-analysis of summertime indoor temperatures in new-build, retrofitted, and existing UK dwellings

Abstract

This article presents the results of a meta-analysis of hourly indoor summertime temperature datasets gathered during the summer of 2013 (May to September) from 63 dwellings located across the UK. The sample consisted of unmodified dwellings (existing), dwellings with varying levels of fabric improvements (retrofitted), and dwellings constructed to higher levels of the Code for Sustainable Homes (new). Indoor and outdoor temperature data from bedrooms and living rooms from these homes were collected at 5-min intervals using temperature sensors. These data were processed and analyzed for summertime overheating, using both static criteria (CIBSE Guide A) and the criteria associated with the EN 15251 adaptive thermal comfort model (CIBSE TM52). The results show that despite a relatively cool summer, sufficiently high temperatures were found in a high proportion of dwellings, which were overheated according to the static criteria, although the prevalence of overheating was found to be much lower when assessed by the adaptive method. Considerably higher temperatures were found in bedrooms, much higher than those in living rooms. Interestingly, dwellings with higher levels of insulation experienced overheating twice as frequently as uninsulated dwellings. It is necessary to consider the overheating risk during the design and retrofit of homes to avoid air-conditioning in future.