Preliminary on-field investigation of Indoor Environmental Quality (IEQ) – a comparative assessment of traditional vernacular, neo-vernacular and contemporary residences

Abstract Indoor Environmental Quality (IEQ) is a concept to understand and assess occupant comfort in buildings. It is evaluated in terms of four aspects namely thermal comfort, visual comfort, acoustic comfort and indoor air quality. This study assesses the IEQ of vernacular structures and compares it to that of contemporary dwellings in a hilly village named Rakkar in Dharamshala, Himachal Pradesh. An on-field investigation of 06 houses of traditional vernacular, neo-vernacular and contemporary architectural styles was conducted which included collection & analysis of objective and subjective data. Readings of 8 environmental indicators were taken using handheld devices. Additionally, a survey of the occupants was conducted which provided insights into their experience, adaptation and satisfaction levels with respect to the four aspects of IEQ. Results indicate that for thermal comfort, neo-vernacular dwellings perform the best followed by traditional vernacular buildings due to their high thermal mass. The study also records lack of thermal comfort in cooking spaces of traditional residences due to excessive air infiltration. In terms of visual comfort, one of the contemporary structures performs the best due to its high window-to-wall ratio, but this comes at the cost of poor thermal comfort. There are differences in objective readings of acoustic environment and indoor air quality in the 3 typologies, but they are found to be within acceptable limits as per Indian & international standards, and the occupants are generally satisfied in terms of aural comfort & IAQ. Findings from this research provide insights into the building envelope parameters that contribute to a good indoor environment. These building attributes can be used to design energy efficient buildings that enhance occupant comfort, thereby consuming less energy during their operational life.