A cool idea on the roof can bring down slum home heat

NEW DELHI: Bijal Brambhatt and her team at Ahmedabad-based Mahila Housing Sewa Trust (MHT) have been working to make life a little more comfortable for slum women — by advocating better living conditions and access to affordable housing. Amng their innovative interventions are cooler roofs in slum houses to bring down the indoor temperature in the summers.
When MHT learnt about the urban innovation challenge in Delhi, the cool roof idea seemed ideal."Our focus is to make the lives of the urban poor better," says Brambhatt. "This intervention can be useful in Delhi’s severe heat. It can also help make the community resilient to climate change."
MHT’s roof projects in Ahmedabad and Bhopal have demonstrated how modular roofs can bring down temperature by 5-6 degrees Celsius. "To build these roofs, we have tied up with a company that uses recyclable materials like copra or other agricultural wastes. Simply painting the roofs white and making it reflective can bring down temperature by up to 2 degrees," says Brambhatt.
While other innovations like growing creepers on the walls and making a rooftop kitchen garden can help cool homes too, the modular roof is suitable for Delhi because it also brings down energy costs. "Poor light and ventilation make people depend more on electrical lighting and cooling devices, and the dwellings are often constructed with materials that absorb heat and require more energy to cool down," reads MHT’s proposal for the challenge. "Slum communities often use cooling fans for hours, raising their monthly energy bills, especially during summers."
To begin with, MHT aims to install modular roofs in 150 households in three slums of Delhi to reduce ambient indoor temperatures and improve ventilation.
If Brambhatt and the team win the Urban Labs Innovation Challenge, the Rs 2-crore prize money will be used to demonstrate and measure how such roofing can improve health and productivity and quality of life. As the proposal statement says, "Access to light, ventilation, and efficient energy is critical to improving the quality of life and productivity of the poor, especially women who spend the majority of their time indoors."