As well as being cheap, bamboo appears to have remarkable qualities of seismic resistance. Now it's being used to try to protect people from earthquakes.

When a 7.8-magnitude earthquake struck Ecuador in April 2016, the coastal city of Manta was heavily damaged. Its vibrant central commercial district, Tarqui, was levelled completely. City streets were scarred by deep fissures that swallowed the brick and concrete rubble of buildings.

Today, Manta is largely rebuilt, but one unexpected part of the legacy of that earthquake is still visible. In the area that was the city's ground zero during the earthquake, a fish market stands beneath a bamboo pavilion by the shore. There's the tourist information centre, a restaurant and a fire station, all built with bamboo. In fact, throughout the city and the surrounding province of Manabí, hundreds of traditional bamboo homes still stand.

"They were all built before the earthquake," says Pablo Jácome Estrella, the regional director for Latin America and the Caribbean at the International Bamboo and Rattan Organization (Inbar). "They stayed standing."

Bamboo has been used as a building material for millennia in South America, Africa and Asia, and grows in abundance in many countries in these regions. But only recently has its seismic resilience started to be more widely recognised through a growing body of research and laboratory shock tests, which indicate that its remarkable natural properties could make it ideal for withstanding earthquakes. Today, construction projects across the world, from the Philippines to Pakistan to Ecuador, are seeking to utilise the natural material that engineers and architects compare favourably to steel.

People on Ecuador's coast used to wait for the quarter moon to harvest bamboo before carrying it into the sea to clean and preserve it, Jácome Estrella says. "We say we have 10,000 years of history of bamboo," he says. Other cultures have also long used bamboo to construct ceilings or other interior elements.

Despite this history, bamboo's potential was not always obvious in Manabí. In the 2000s, Jácome Estrella says, a local architecture professor in Manta realised the city's fire department prevented bamboo construction, believing it to be flammable (which it naturally is, but this can be reduced using fire-retardant treatments). So he started working as a volunteer firefighter. "He convinced them to build a fire station with bamboo," he says.

That fire station, with its sweeping vaulted roof large enough to accommodate several hook-and-ladders and water tankers, survived the 2016 earthquake. "Nature designed it to bend," says Bhavna Sharma, an associate professor at the University of Southern California whose research focuses on the use of bamboo in construction.

Bamboo culms (the upright, hollow stems) are lightweight, reducing the mass of a structure, and research shows that the ductility that allows them to withstand high winds also allows them to absorb seismic shock. "Buildings should move in an earthquake," says Sharma. "We just want to control how much they move."

A post-earthquake survey of over 1,200 buildings in Manabí found that overall, reinforced concrete buildings experienced greater levels of damage than timber and bamboo buildings, says Sebastian Kaminski, a structural engineer for UK-based construction consulting firm Arup, who was part of this mission. However, the trend was reversed in some towns, he notes, adding that post-earthquake data also needs to be taken with some caution. In this case, for example, it was collected several weeks after the event, when many buildings had already been demolished.

Today, a project launched in 2021 by Inbar and the Spanish Agency for International Development Cooperation has built hundreds of new bamboo homes in Manabí, the Ecuadorian province where Manta is located. It has also taught some 200 students at the University of Manabí bamboo construction techniques, such as treating bamboo stalks and assembling panels.

It costs less than $20,000 (£14,900) to build a two-bedroom home, Jácome Estrella says – about the same as a house built with more conventional materials. "There is a phrase we use: it's the wood of the wise," he says of bamboo. "[It] is renewable, sustainable, with low impact to the market."

These new homes are inspired by a traditional building method called bahareque, known in English as wattle and daub, where a mesh of bamboo is covered with a layer of wet loam soil.

Researchers began looking seriously at bamboo around the turn of the century. In 1999, after a 6.2-magnitude earthquake........

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