Appraisal of Building Elements and Indoor Climatic Parameters for Free Running Buildings of North East India
Abstract
Energy Statistics Data of 2007-2017 shows that apart from commercial and recreational buildings, domestic buildings account for consumption of 24% electricity produced on a whole (Biswas, 2014).Buildings account for 35% of total final energy consumption in India today, and building energy use is growing at 8% annually [1]. The dependence on HVAC systems are increasing in most tropical countries, to achieve thermal comfort conditions irrespective of building design conditions. It becomes difficult to assess or identify the loopholes of a free running building in terms of its thermal comfort and its causes. It is important to note that there are differences in thermal acceptability or adaptability for users of naturally ventilated buildings compared to users of buildings with air-conditioning [[2]]. In the case of free running buildings, users are more tolerant of indoor thermal conditions [[2]]. Assessing the indoor thermal comditions as an effect of the built envelope is one of the challenges and considerations of sustainable architectural design. Microclimate of an area contributes to the emergence of traditional practices in the built form of the area as a response to obtain optimum comfort. But with advancement in the technology and economic strata, people now opt for more conventional mode of construction in building typologies. Studies reveal comparison of different thermal comfort conditions with respect to indoor spaces by evaluating several indices and methodology. Many models have evolved through time to validate studies regarding acceptable indoor temperatures and built forms, often lacking real time data, which has been compensated by using mathematical models. ASHRAE 55-2013 defines thermal comfort standards based on the laboratory experimental results which are conducted on site as well as climate chambers.
Field studies for naturally ventilated buildings have been done internationally as well as in India [[3], [4]], mainly focusing on qualitative description and analysis of thermal performance of few houses. The north eastern part of India holds account of few studies related to the relationship between building parameters and environmental parameters.
Identifying the gap, the paper aims to conduct experimental investigation on various building and study building elements and its effect on real time instrumented data of indoor climatic conditions for houses in three different sites of North East India, for the summer season. The intent is to understand the correlation of different building elements with climatic parameters like temperature, humidity and wind speed with the help of quantitative evaluation to understand variation in indoor conditions. This paper intends to examine the consequence of building elements like morphology, orientation, window to wall ratio (WWR), Surface area to volume ratio (SA/V), Window to Floor area Ratio (WFR), etc. in the free running houses in warm humid and cold humid climates. Standard codes and mandates have been effectively compared for similar climatic areas, to prescribe suggestive ranges of building elements to improve overall building envelope performance. In this study, a field study is conducted in a total of, 21 free running traditional buildings called IKRA houses, and 9 free running modern typologies in North East India. Samples of housing were selected in ten numbers for each site which were documented and developed for calculation of the parameters.
