Indonesia needs earthquake resistant houses. Building them is a huge problem.


Deadly earthquake that turned buildings into ruins West Java, Indonesia once again exposed the danger of living in poorly built houses in one of the most seismically active zones on the planet.

After Monday’s quake, survivors slept awake or in shelters away from homes that could collapse as tremors shake buildings already hit by the 5.9 quake that killed at least 271 people.

The quake’s shallow depth of just 10 kilometers (6 miles) increased pressure on structures in West Java, where more than a million people were hit by very strong shocks, according to the US Geological Survey (USGS).

Visiting the site on Tuesday, Indonesian President Joko Widodo promised that the damaged houses – more than 56,000 of them – would be rebuilt to become earthquake-resistant.

“The Department of Public Works and Public Housing requires that homes affected by this earthquake meet earthquake-resistant building standards,” he said. “These earthquakes happen every 20 years. Therefore, houses must be earthquake resistant.”

But in a developing country where about 43% of the population lives in rural areas, mostly in unsafe and poorly built homes, the challenge of building earthquake-resistant buildings remains a huge challenge.

More than 61,000 people have been displaced as of Thursday, according to the National Disaster Management Agency (BNPB), and experts say the damage could be mitigated with proper infrastructure.

A man reacts as rescuers search for victims in an area hit by landslides after the earthquake that hit Chanjur, West Java province, Indonesia on November 22, 2022, on Monday.

Indonesia, an archipelago of more than 270 million people, is located along the Ring of Fire, a strip around the Pacific Ocean where most active volcanoes are located and where most earthquakes occur when tectonic plates collide with each other, causing tremors.

Of the 271 people who died in Monday’s quake, at least 100 were children, many of whom were at school when the quake struck. BUT 6 year old boy was pulled alive from the rubble of his home two days later, but many others were less fortunate.

The earthquake shook the foundations of buildings, causing concrete structures to collapse and roofs to collapse. The photographs showed fragments of metal, wood and bricks. According to the governor of West Java, Ridwan Kamil, most of those killed were crushed or squeezed under the rubble. Others died in landslides.

Cleo Gaida Salima said that when she heard about the earthquake, she tried to call her mother in Kugenang, Chanjur, but after receiving no answer, she decided to go there from her home in Bandung on a motorcycle.

The journey – about 65 kilometers (40 miles) – usually takes less than two hours. But with roads completely blocked by landslides, it took her 24 hours.

“All the houses were covered in dirt and mud,” she said, adding that she was reunited with her family who survived the earthquake.

“We all cried with excitement and happiness,” she said. “Our whole family immediately ran to escape. The earthquake was very strong.”

An Indonesian search and rescue team evacuates bodies from collapsed buildings in Cianjur county, West Java province, November 22, 2022.

In Indonesia, houses have traditionally been built with organic building materials including wood, bamboo and thatch grass due to the country’s hot and humid climate.

They were considered stable houses and largely strong in the event of an earthquake. However, increased deforestation and the high cost of timber have prompted people to choose alternative materials, according to a 2009 study on disaster recovery in Indonesia by the Association of Architectural Sciences.

More and more houses were built of brick and concrete, and while the façade may have looked modern, the structure underneath was poorly bonded, the study says.

What’s more, poor concrete quality and poor steel reinforcement make these structures increasingly vulnerable to collapse during an earthquake, while causing maximum damage due to the weight of the materials, the report says.

A man stands near houses damaged by the earthquake in Chianjur, West Java province, Indonesia, November 21, 2022.

Earthquake structures are designed to protect buildings from collapse and can work in two ways: by making buildings stronger, or by making them more flexible so that they sway and slide over shaking ground rather than collapse.

Architects have been developing this technology for decades, and engineers often adapt materials and methods to local conditions.

Architect Martin Schildkamp, ​​founder and director of Smart Shelter Consultancy, said his company helped build about 20 schools in earthquake-prone Pokhara, in the central region of Nepal, seven years before the massive earthquake.

More than 8,000 people died when the earthquake hit in 2015, but schools built using traditional techniques and materials from the landscape, such as rubble masonry, did not collapse.

“Our schools didn’t collapse,” he said. “They received only some cosmetic damage.”

He said that in developed countries such as Japan, knowledge, infrastructure and money are readily available to build earthquake-resistant buildings, but the high cost of building such structures makes it difficult in developing countries.

According to Schildkamp, ​​in Nepal, many people build their houses with mud mortar, which is very fragile. “If it is completely unreinforced, there is no additional reinforcement in the building. It’s something that collapses very easily,” he said.

Schildkamp’s team used cement mortar and inserted horizontal rebar posts into the structure to reinforce it, instead of vertical ones.

Building codes should prevent the proliferation of poor-quality buildings, Schildkamp said, but in some countries governments are not doing enough to enforce the rules.

“We need knowledge and strategy in these countries. And we need governments to make these building codes mandatory,” he said.

In West Java, hope is fading that more people can be pulled alive from the rubble of the earthquake.

Earthquakes are also making work harder, and residents now live in fear that the next natural disaster could bring down their precarious homes again.

Although President Widodo said the government would provide compensation of up to $3,200 to each owner of a badly damaged home, many families in Chianjur lost everything. And now they face the near-impossible task of recovery.