THERMAL ACCEPTABILITY ASSESSMENT IN VERNACULAR BUILDINGS OF COLD AND CLOUDY REGION OF NORTH-EAST INDIA

Thermal performance study is one of the critical aspects of the natural ventilated vernacular buildings. Thermal comfort studies of built environment mainly focussed on two different approaches, one is heat balance approach and the other is adaptive approach. Thermal comfort survey has been carried out in 50 houses covering over 100 occupants of cold and cloudy climatic zone of North East India. This comfort study has been done in the form of long term thermal monitoring at outside and inside of a house, comfort survey based on ASHRAE thermal sensation scale for different seasons of the year. Comfort temperatures are calculated based on Humphreys and Auliciems comfort model. Neutral temperatures at which people feels comfortable in this natural ventilate buildings are obtained from the comfort survey. It has been found that the comfort temperature obtained from the Humphreys and Auliciems comfort model differs with the neutral temperatures obtained from comfort surevy. There are four major indicator like outdoor and indoor temperatures, relative humidity and clothing pattern of the peoples has direct impact on the peoples perception and acceptabilty on comfort situtaion. In this study, thermal comfort equations are developed based on these four indicator and validated with the neutral temperature obtained from comfort survey. It has been found that the comfort equation developed with all these four indicators has highest co-relation coefficient and provide the neutral temparture values very close to thermal comfort survey results. However, these equations are valid only for similar kinds of natural ventilated buildings and also for similar kinds of building functioning management of this climatic zones. It is also not appropriate to obtaine a genralized thermal comfort model as the adpation process and the expectation and perceptation of the peoples are region specific and also differs with socio-cultural norms.