Evaluating the Effect of Building Envelope on Thermal Performance of Houses in Lower Himachal Pradesh

Buildings are the major component of built environment. Creating comfortable indoor living environment for users is the primary objective of building design. The building envelope plays a crucial role of both protecting its occupants from external environment and controlling the indoor environment. Hence, selection of building envelope materials is critical in maintaining indoor thermal comfort condition and its energy performance. The main aim of present-day building design should be eliminating the need for mechanical heating and cooling equipment. The climate in Himachal Pradesh, India, varies with increasing altitude from "subtropical" to "cold-desert" climatic condition. The study area, Hamirpur town of Himachal Pradesh, has "subtropical" climate with hot summers and cold winters. Field studies of naturally ventilated residential buildings with different building envelope materials found in Hamirpur were conducted in winter months of 2013 and 2014 to evaluate their impact on indoor thermal condition. The optimum indoor comfort temperature in winter months for naturally ventilated residential buildings in Hamirpur (HP) is found as 16.5 degrees C, with thermal comfort temperature range 15.7-16.9 degrees C. Based on this study, suitable building envelope materials for houses are recommended to maintain indoor thermal comfort and energy efficiency for holistic sustainability of built environment.