Thermal comfort and energy consumption in residential buildings

Abstract

A large amount of construction activity has taken place across the Maltese Islands in the last years resulting in many towns and villages being overshadowed by high-rise apartment buildings, described by many as a 'concrete jungle'. A number of reasons could be attributed to these construction booms amongst which were new government policies, revised development boundaries, as well as Malta's entry within the European Union in 2008. Unfortunately, not much thought was given to indoor thermal comfort and energy consumption during the design and/or implementation phases of these new buildings, despite increasing concerns over the ever increasing utility tariffs. Inefficient building construction methods and materials have resulted in uncomfortable indoor thermal environments together with the resultant increase in running costs. A study of a number of residential dwellings from both the social housing and the private sector was carried out in order to assess the indoor thermal environment and the occupants' energy consumption. Three different dwelling types situated in four different localities were chosen consisting of ten apartments, two terraced houses and one house of character. The required thermal performance of each building envelope was obtained for each monitored bedroom and living room and the thermal comfort and wetness of the buildings were assessed. Physical parameters indicated that the thermal comfort levels within many of the dwellings were insufficient and only those dwellings which had adequate wall and roof insulation installed resulted in a relatively comfortable indoor thermal environment. One of the main external factors which affected :he indoor temperatures was overshadowing by adjacent buildings - an ever increasing problem in terraced house areas where changes in the zoning have resulted in the construction of three to four storey apartments adjacent to two-storey dwellings. Annual energy consumption, in terms of floor area and per capita, through utility bills and EPRDM calculation software was assessed and, together with adequate building insulation and the use of renewables, the importance of consumer behaviour emerged as one of the decisive factors in the final energy use of a building.