Floating Schools and Green Mortgages: Constructions to Help the Urban Poor

Locals play in the sea on Chowpatty Beach as the sun sets behind Malaba Hills (the Manhatton of Mumbai) in Mumbai, India
Locals play in the sea on Chowpatty Beach as the sun sets behind Malaba Hills (the Manhatton of Mumbai) in Mumbai, India

As slums, schools, and homes are designed and built in cities across the developing world, the urban poor are making use of new and innovative approaches to construction. A key element is sustainability: many of these approaches make better use of local materials, use energy and water more efficiently, and reduce waste and pollution. But sustainability is not the only prerequisite for success. Community input and collective decision-making, for instance, contribute to more favorable outcomes. Can these techniques be used successfully in other cities? Read on to see examples of innovative approaches to construction in Lagos, Nairobi, Mumbai, Mexico City, and Rio de Janeiro -- then discuss the scalability of these approaches on urb.im, the platform for just and inclusive cities.


In Lagos, Makoko Slum -- where many houses are built on stilts over the polluted, dark waters of the waterfront and lagoon -- is perceived as a development blight and hurdle to the city's development. To counter this perception, and to adapt innovatively to challenging circumstances, an urban planning firm has designed a prototype school to float on Makoko's waters. The school, currently under construction, employs modern green principles that coincide with local inspirations and the community's own methods for adapting to their environment.

In Nairobi, old construction methods were combined with new designs to build a school in the city's slum. The primary school was built in a low-cost, eco-friendly way, and as a collaborative effort between slum residents and architect volunteers. Instead of using increasingly popular -- but expensive and polluting -- industrial construction materials, the team employed a traditional rammed-earth construction method, using cheap and environmentally friendly, readily available resources.

The Indian government's plan for turning Mumbai into a "world-class city" ignores 60 percent of the population who live in informal settlements. Instead of ignoring them, some programs help these slum residents improve their homes, by providing them with ready-mix concrete, which is of higher quality than concrete mixed on site, and technical assistance to enhance construction laborers' skill sets. And instead of slum rehab schemes involving resettlement, organizations advocate for a multi-faceted approach including the rationalization of building codes.

The Mexican federal government has developed a housing policy called the Green Mortgage (Hipoteca Verde), which promotes sustainability through a credit model initiative: it's a technology package that consists of increasing the amount of credit needed to acquire housing, in order to use energy-efficient technologies to reduce water and energy consumption. Higher mortgage payments are compensated for by lower energy and water costs. These technology solutions -- such as solar heaters, energy-saving lamps, water-saving valves, thermal insulation and high efficiency air conditioners -- result in up to 48 percent savings on energy consumption. Not only does this program lower a household's energy expenditure and reduce pollution, it also fosters a culture of saving, and protects citizens' access to housing.

The Rede Sarah Hospital in Rio de Janeiro, is a recent example of a design-oriented public building recognized not only for its impressive design, but also for the high-quality rehabilitation and physiotherapeutic services it provides, free of charge. The construction has abundant open-air spaces that take advantage of the city's good weather and promote outdoor therapies and workouts. The special aluminum materials used in several parts of the building contribute to improving ventilation, and the structure also allows for plenty of natural light to stream through the building, all of which is uncommon in hospitals.

As these examples show, thoughtful construction is possible, affordable, and can make a difference when it comes to the urban poor's schools, homes, and hospitals. Join us on urb.im, the global community for just and inclusive cities, to read more on this topic and to add to the conversation.