Urban Climatic Design

Urbanization is the most transformative trend of 21st century being witnessed by mankind. The United Nations 2018 report envisages Delhi to be world’s most populous city by 2028 with 37.2 million people. As per McKinsey, it is expected that India will add more than 20 billion square metres of residential floor area to meet the housing needs of the increasing population. The paper investigates three key phenomena in the rapidly urbanizing Delhi Metropolitan region: Climate change, housing demand and its impact on outdoor thermal comfort. As Delhi urbanizes rapidly, witnessing large scale high density residential development it’s contributing to the majority of built volume in cities. The main hypothesis of this applied and action based research is that urban housing typologies, morphological transformations and changing spatial patterns have been playing a major role in contributing to urban heat islands. There is an urgent need to study the relations between housing form, micro climate, climatic indices and consequent impacts on urban heat islands in outdoor conditions. The aim is to evaluate contemporary housing typology on the basis of factors influencing its built form such as master plan, building regulations, stakeholders, logistics, real estate forces, changing technology etc. and their response to climatic variables such as temperature, humidity, wind, radiation etc. The objective is to conduct study of micro climatic variables in the metropolitan region of Delhi. Form-climate relations have been investigated at the local level in six sites in Delhi by conducting field based survey using calibrated instruments and tools for site based measurement. The focus areas are on the peripheral areas of the city which are predominantly residential in land use with plotted housing, mid-rise walk up apartments and high rise group housing forming distinct morphological districts. The inferences from these six site studies have been demonstrated via integrated modelling and simulation tools to underline the complex interdependencies between transforming three-dimensional urban typologies and newly emerging heat island effects. This research project aims to add important insights on how new parametric simulation tools can assess the impact of newly emerging urban typologies on urban thermal environment forming distinct districts. The proposed output of the analysis will enable to devise form based guidelines for spatial planning and design to evaluate the environmental performance of housing morphology. Various dimensions of housing design decisions like distance between buildings, shade factor, orientation, built envelope, and open space structure will be informed through the use of the modelling tool. The outcomes of this research will support developers, architects and urban practitioners in taking informed decisions in the development processes, integrating urban development and sustainability. The research project aims to focus and strengthen disciplinary knowledge in building climate friendly and sustainable urban environment by investigating relationships of urban housing form and outdoor thermal comfort with Delhi as a case. Beyond this research the study further aims to simulate various development alternatives to illustrate how urban heat islands can be mitigated through spatial planning and design.