Delphi-AHP-Fuzzy Computational Approach to Sustainability Assessment Model and Indian Traditional Built Forms

Sustainability is the key issue in a rapidly developing world which has its influence felt in the construction and real estate sectors. Ecological, economic and socio-cultural issues are in the core of planning, construction, and operation of built forms. Developments in today's world pertain to environmental issues, energy, water resource consumptions, pollution and global warming which compel the adoption of sustainable built forms. The national rating system-GRIHA is in force to regulate sustainable developments and LEED has exercised considerable pressure on Indian context. However, it is arguably once if LEED-India and GRIHA are adopted in diverse climatic zones of the country, respective local culture and societies with varying economies, whether these produce the much-needed end result; sustainability. Mostly, LEED-India is designed to address environmental concerns and building standards. The national green building rating system GRIHA is following the same model for all climatic zones compromising the local and regional variations. The review establishes that these rating systems mainly focus on the environmental performance assessment. However, these do not effectively address the wider sustainability issues. It will, therefore, require an appropriate and pro-active an alternative sustainable built form assessment rating system. Traditional models sustain on their own design and features with acceptable sustainable performance. Research combined three methods to develop a unique model for assessing the sustainability of traditional built forms. Among these methods, the Delphi group decision-making method provides co-design features, the Analytical hierarchy process (AHP) includes Multi-Criteria Decision-Making (MCDM) techniques, and Fuzzy Logic (FL) theory can simplify complex internal and external factors into easy to understand numbers or ratios that facilitate decision-making. In addition to these, an interview-based questionnaire survey is also conducted among vernacular-traditional households to understand their perception of vernacular-traditional buildings and simultaneously recorded physical measurements and climatic data. Adopted methodology and survey interpretation lead to develop an alternative sustainability assessment model for built forms based on local and regional conditions.