Relation Between Indoor Thermal Environment and Renovation in Liege Residential Buildings

Indoor thermal environment monitoring has been done in 20 residential buildings of Liege city followed by questionnaire based comfort survey amongst the occu- pants of 85 houses in order to record their preference and expectations about in- door thermal environment in winter and spring season. It is found from the anal- ysis that change of glazing has a minimum or even sometimes an adverse effect on the existing indoor environment due to the absence of proper insulation of the rest of the building envelope. It is observed that in winter there is a sudden drop in indoor temperature and also overheating in summer. This is due to unplanned installation of glazing which actually increases the fenestration area ratio lead- ing to higher indoor temperature fluctuation and causes discomfort. It is also im- portant that the occupant’s preference and expectations as well as overall as- sessment of indoor environment needs to be consider towards energy efficiency improvement.