How do you fight a heatwave when your home is a furnace?

The heat arrived early this year. Long before peak summer set in, much of India was already feeling its breathless weight. Temperatures soared past the 40-degree mark, and nights offered little relief. According to the India Meteorological Department, an extended and intense heatwave is expected across large parts of central, northern, eastern, and southern India this summer.

When a house traps more heat than it keeps out 

Delhi is among the worst hit, where the heat isn't just a weather event; it's a daily hazard. In the city’s informal settlements, packed with homes made of tin sheets, concrete blocks, and minimal ventilation, the air inside is often hotter than the world outside. The rising temperatures are not just uncomfortable. They are dangerous, especially for the elderly, newborns, daily wage workers, and mothers recovering from childbirth.

One such settlement is Delhi's Sultanpuri, where the heat crisis unfolds in heartbreaking detail. Inside a small 13.6 square foot home, Poonam, who works at a bag factory, struggles through suffocating afternoons as her cement sheet roof turns into a hotplate. When the sun peaks at noon, her walls radiate heat, and the air hangs heavy and unmoving. She is not alone. Throughout this community, countless families face the same daily battle against the heat. 

Kalindi, a daily wage labourer, shares a small house with her family of five, where the heat seeps into their skin and bones—inside and out, there is no escape. And not far from them, Aarti faces an even greater challenge. Recently recovering from a caesarean delivery, she must care for her newborn in a room that feels less like a refuge and more like an oven. These are not isolated stories. They echo across Delhi's informal settlements, where heat is not just discomfort but a crisis.

Building resilience, one roof at a time

The goal is to help vulnerable communities anticipate better. Early warning systems provide alerts that enable people to survive emergencies such as extreme heat. Working with communities and providing them with affordable solutions brings multiple benefits. Preparing them for emergencies is a precursor to a speedier recovery. Through these learnings, communities begin to adapt to changing conditions, and ultimately, the hope is that they can thrive.

Over the past few years, efforts have been implemented to mitigate heat in vulnerable areas. Backed by learnings from the summer of 2025, we have created living laboratories in two neighbourhoods of north-west Delhi that are at extremely high risk from heat. In these dense, underserved areas where cooling is a matter of survival, the goal is to test nature-based innovations as cooling roof options.

Does cooling roofs without high-tech installations but thoughtful, practical innovations rooted in science and traditional wisdom become a lifeline for these vulnerable communities? Developing a series of prototypes, each tailored to specific living conditions, ventilation levels, and material availability, the objective of these initiatives is to ensure the models are affordable, easy to install, and can be implemented by local communities.

Creepers and bamboo: Green canopies of relief

Bamboo frames layered with creeper plants have provided shade and cooling in more open spaces. Kalindi’s home was one of the first to receive this intervention. The creeper plants grew steadily, forming a green barrier that softened the sun’s glare and cooled the space beneath. Her home, which was once reaching 38 degrees Celsius indoors, felt noticeably cooler at 35.6 degrees Celsius. This simple structure became an oasis for a family living hand to mouth.

Aarti’s home received a more layered response as they used a combination of jute bags fixed on bamboo framing and sprayed with water. Her roof became a canopy of protection. Despite the harsh 37.20 degrees Celsius outside, the inside remained at 31.26 degrees Celsius. That slight drop mattered more than numbers could explain. It allowed a mother to heal and a newborn to rest.

These innovations are not limited to just these three families. Many others across Delhi’s informal settlements have benefited from different prototypes, tailored to the unique challenges of their homes. In some households, Magra cloth—a coarse fabric made from discarded wool of the Magra sheep, native to Rajasthan—was stretched over bamboo frames to create breathable, shaded spaces that brought temperatures down by several degrees. The wool’s texture and insulating properties make it ideal for regulating indoor temperatures, providing cooling in summer and warmth in winter. This meant indoor readings of around 34.2 degrees Celsius despite the 40 degrees Celsius outside. 

Community-led, low-cost, scalable solutions

These initial measures drawn from Delhi's informal settlements are part of a broader movement to build resilience. The initiative focuses on low-cost, locally made, and community-informed solutions. Even when the temperature drops, and the recorded differences may seem modest, their human impact is profound. They offer rest to the exhausted, healing to the unwell, and dignity to the forgotten.

As heatwaves become more frequent and severe, especially in urban and peri-urban areas, this critical work done in partnership with NDMA offers a path forward—one where climate resilience is not abstract policy but real, tangible support felt on rooftops and in living rooms. These nature-based solutions show that adaptation doesn't always require heavy infrastructure or complex systems. Sometimes, it just takes paint, bamboo, jute, or a few plants—and the belief that every home, no matter how small, deserves to stay cool and habitable.

The author is the coordinator for the 2025 Under The Umbrella campaign launched by the Sustainable Environment and Ecological Society (SEEDS).