Energy savings from secondary windows

Abstract

This paper is one of a series of reports for an EEC Contract on field, laboratory and theoretical investigations of energy saving methods in dwellings. Here, specially prepared matched-house pairs have been used to investigate the energy savings obtained from fitting secondary windows. This forms part of an ongoing programme designed to examine a range of energy conservation measures. These particular results demonstrate a mean reduction in energy consumption of 12 per cent (3 per cent) for the secondary windows. The theoretical percentage reduction agrees well with that measured only if the air change rate is assumed to have been reduced by about one third. Energy consumption has been determined for a range of weather conditions which, from data gathered on the experimental houses in other heating seasons, should be representative of the average annual savings for this type of house and pattern of usage.