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MPhil in Engineering for Sustainable Development

global challenges, engineering solutions

Studying at Cambridge


Ramit Debnath

Comfort, energy use and well-being in informal settlements: Investigating the rebound phenomenon in the slum rehabilitation housing of Mumbai using a backcasting approach

Despite progressive policies aimed at slum eradication or rehabilitation, urban slums in India have expanded, and their population have increased. In this study, we investigate the fate of slum rehabilitation policy in Mumbai that has a ‘rebound’ characteristic, i.e. rehabilitated occupants move back to their original horizontal slum. Here we investigate the occupants’ neutral state of comfort in their built environment, known as ‘homeostasis’. The causes for the loss of homeostasis in the slum rehabilitation housing using a novel backcasting methodology and a fault tree analysis was attempted here. Thirty household surveys were conducted in a slum rehabilitated colony in Mumbai, India. Results show that the primary cause of loss of homeostasis is related to economics and built environment related distresses. High expenditure on buying household appliances and increased electricity bills are a significant cause of economic distress. While poor indoor air quality, social isolation and feeling of loneliness were the determining factors of built environment induced distress or discomfort. The causal pathways derived through the fault tree analysis revealed zones of countermeasures based on which we propose a cooperative based women-led self-help group model to mitigate the loss of homeostasis. Such model adds a loop of accountability to the current slum rehabilitation process to improve its sustainability. This study extends the current state-of-the-art in backcasting for sustainability methodology and addresses the shortfalls in the current slum rehabilitation process in Mumbai.