By Nidhi Jamwal, Climate Journalist, Mumbai, India

Rubina Bibi is a 37-year-old widow who lives in a congested slum in Andheri (West) in Mumbai, India’s financial capital. Like most of the fellow slum dwellers, her home is a compact one-room of plastered brick walls and a tin roof. The room has no window. The door is made out of a discarded tin-shed. In a corner of this tiny room sits a stove on which Rubina cooks for her three children and old mother.

“Our room is nothing but a bhatti [large oven]. Summers become unbearable as the heat and high humidity in Mumbai makes it claustrophobic and suffocating. The tin roof adds to the heat,” said Rubina, who is a migrant worker from Murshidabad in West Bengal. She works as a domestic worker in nearby skyscrapers to make a living. The monthly rent of her hot-oven-room-home is Rs 7,000.

During summers, a proper night’s sleep is what Rubina and her children crave the most. She often gets scolded for coming late to work because almost the entire night she is unable to sleep, which affects her productivity and leads to loss of wages.

“My room has no window. At night we have to close the tin door, as I have two teenage daughters and cannot risk their safety,” she said. “Five of us spread mattresses on the floor and sleep. We cannot even spread our legs properly due to lack of space. Cooking inside the room adds to the heat. I feel sick all the time,” she narrated.

The plight of Rubina and her family is the story of millions of urban poor in Mumbai and other metropolises of India, who live in cramped informal settlements where heat gets trapped and there is no ventilation to provide minimum relief.

Research and lived experiences of communities tell us that ambient temperature in unplanned slum settlements is often a couple of degrees higher than in planned, swanky neighbourhoods in cities. Some neighbourhoods and communities can feel hotter than others in the same city on the same day.

A study by World Resources Institute (WRI) India, published in 2020, reported that slum settlements in Mumbai are five to six degrees warmer than their neighbouring housing societies, while 37 per cent of the city’s buildings with metal roof structures are exposed to a risk of high rise in temperatures or heat risk post monsoon.

This heat inequity is recorded in the Municipal Corporation of Greater Mumbai’s (MCGM) report titled Implementation Pathway for Addressing Heat Risks in Buildings Sector for Identified Hotspots in Mumbai. It notes that some areas in the metropolis were observed to be 6-8°C warmer than the nearby residential zones, which could be attributed to high-density construction, low green cover, use of heat-retaining building materials and the urban heat island effect. The choice of building materials and prevailing design practices significantly contribute to indoor and outdoor heat gain.

Nature-based solutions (trees) and low-cost cooling options like solar-reflective roofs, khus curtains, cross-ventilation designs, etc can help bring down the temperature in slum households. It is imperative that heat inequity and the thermal comfort of marginalised and vulnerable communities must be central to all urban planning and climate action projects.

Disclaimer: The views expressed in this piece are those of the author(s) and do not necessarily reflect the views or policies of AIDMI.