Bjorn Soderburg, co-founder of Build Up Nepal, an Earthshot Prize 2024 finalist, traveled as a young man to Nepal to volunteer for six to twelve months. That was 23 years ago. His career has involved developing social enterprises in Nepal, but in 2015 his work took on a new focus.

In April 2015, a massive earthquake struck Nepal killing thousands of people and destroying 800,000 homes. Living in Kathmandu, Bjorn and his wife saw widespread damage, but when they visited a nearby village they were shocked to find there wasn’t a single house left standing. More than a thousand homes were gone. Bjorn says, “It looked like a war zone”.

They helped build temporary shelters and distribute tools so the residents could rebuild. The homes — like their predecessors — were built from stone and mud.

Woman walks through rubble in Jajarkot after earthquake; Photo by Brand Brewers.

The dream

The dream of virtually all poor Nepalese is to someday live in a house made of bricks and concrete. This has been borne out by Build Up Nepal’s research in which they interviewed more than 5,000 people.

But not only are traditional “fired bricks” too expensive for most (and challenging to transport to remote areas), because they are made in coal-fueled plants they are a huge contributor to CO2 emissions and air pollution. According to Bjorn, more than a third of CO2 emissions in Nepal come from factories – even more than from vehicles. Air pollution is also a huge problem, with poor air quality in Nepal becoming more common. “We realized”, explains Bjorn, “that the choice is between stone and mud that won’t survive an earthquake, or fired bricks which are a climate disaster. We thought, ‘we have to find a better way.’”

Bina Shrestha, co-founder of Build up Nepal.

A new — and old — approach

Exploring ways to make affordable bricks without burning coal, they came across a technology invented after an earthquake in Thailand in the 1970s. Made from compacted soil, sand, and a small amount of cement, compressed stabilized earth blocks (CSEB) which are air-dried, seemed like a viable option.

Build Up Nepal purchased CSEB equipment from India and China. “It was,” Bjorn says, “a disaster”. The first machine they bought broke after making ten bricks, and other equipment they found was expensive, required electricity, and was not suited for use in remote mountain villages.

So, Build Up Nepal designed a manually operated machine, making it simple, sturdy, and affordable -— eventually reducing the cost of the machine 5-fold. Their machine, which can be operated by one person or even more effectively with a team, forms blocks that interlock and stack together. They have holes which allow them to be anchored in the ground, making them extremely earthquake resistant.

The result is a structure that is made with materials that result in 80% less CO2 emissions and 90% less air pollution than traditional bricks. And every wall built out of CSEB costs 40-60% less than one of fired bricks. Because of that, a Build Up Nepal house costs roughly the same as a house built out of structurally unsound stone and mud.

Made from compacted soil, sand, and a small amount of cement, compressed stabilized earth blocks (CSEB) which are air-dried, seemed like a viable option.

With several working CSEB machines, Build up Nepal began projects in three villages. The excitement of this was tempered by the fact that “thousands of villages had collapsed in the earthquake, and every year hundreds (more) are exposed to floods and other disasters,” reports Bjorn. “So we felt we needed to get this technology to every town and village across the entire country.”

Workers mix materials for eco-bricks in Jajarkot; Photo by Brand Brewers.

The model

Their solution was to sell the brick making machine to local entrepreneurs. Build Up Nepal provides training in production methods, quality control, and business practices. A phone app with instructional and sales videos, help with social media publicity, and access to radio advertisements are other tools Build Up Nepal provides to help the entrepreneurs grow their business.

Their machine, which can be operated by one person or even more effectively with a team, forms blocks that interlock and stack together.

Each business owner receives several pre-approved house- and building- design plans, and Build Up Nepal conducts workshops to instruct local masons how to build with the blocks, and train mechanics how to repair the machines.

Bjorn explains, “What we’ve seen is that an individual entrepreneur trying to succeed by him or herself is next to impossible. And this is why this technology has not taken off in so many other countries before. What we do instead is that we try to build an ecosystem across the whole country.”

Stacking cured bricks. Photo by Rashik Maharjan.

Currently, there are roughly 200 entrepreneurs actively producing and selling CSEBs in Nepal, and over 10,000 houses have been built. To date, about 75% of the entrepreneurs are operating successful businesses (a rate they’re working to improve), and of those, most recouped their investment within the first year of business, according to Bjorn.

It takes time for people who have never seen compressed earth blocks to trust the product and begin to use it. But once the first few homes are built, adoption spreads quickly. Experience has also shown that every successful entrepreneur creates two more when a neighbor, or a cousin across the country, learns of an entrepreneur’s success.

Entrepreneur with Build Up Nepal’s eco-bricks. Courtesy of Build Up Nepal.

Put to the test

Last year, Nepal experienced another deadly earthquake in which hundreds died, and 79,000 homes were destroyed. Felt across much of western Nepal, it was the largest earthquake since 2015. At the epicenter, very little was left standing, but 24 buildings constructed of Build Up Nepal’s blocks remained intact and undamaged.

As the government and NGOs have dealt with the disaster over the last year, the recognition of the viability of CSEB, and the demand for Build Up Nepal’s technology and expertise has been both exciting and daunting for the organization’s team of 25 people.

As word of their success spreads, interest in Build Up Nepal from other countries and NGOs has grown as well.

The Nepalese government is giving grants to assist with rebuilding and is expected to announce incentives to use green building materials. “When the earthquake hit, we had two entrepreneurs in this area. Now we have 70. We believe that within two months we’re going to have another 20. But what we need is to have 150 entrepreneurs in the next six months.”

Nepalese homeowner and home built with compressed earth blocks. Photo by Rashik Maharjan.

The road ahead

As word of their success spreads, interest in Build Up Nepal from other countries and NGOs has grown as well. Bangladesh, for example, is expected to ban fired bricks in the next two years.

While Bjorn is confident that other earthquake and flood-prone countries could use compressed earth blocks to build low-cost housing, he believes Build Up Nepal needs to remain focused on Nepal right now, noting that “there are 2.7 million houses at risk from the next earthquake or flood.” They are studying opportunities for expansion, but Bjorn says “we need another one to two years to be fully ready to go.”

When he visits a town and sees hundreds of homes built with compressed earth blocks, Bjorn says he’s always amazed. Photo by Rashik Maharjan.

At the same time, Build Up Nepal continues to innovate and test improvements to their technology. In partnership with several organizations, including Swedish Engineers Without Borders and MIT, they have worked to improve the ease of use and durability of their machines, and composition of the blocks.

While buildings made with Build Up Nepal’s blocks require much less cement for mortar and reinforcement, cement is still the most expensive component of the blocks. When they began, their blocks contained 12% cement, which they reduced to 10%, and now to 7%. Their next goal is to get to 5%, and they’ve also committed to be carbon neutral by 2027.

Post earthquake in Jajarkot. Photo by Brand Brewers

A sense of urgency

After decades of working in the climate space, Bjorn believes that having the ability to build safe affordable homes, create jobs, and reduce emissions is not enough. The key to transformational change is to make the solution financially viable. “I believe that the reason why our solution is working,” he asserts, “is because our primary selling point is not the environment. Our selling point is stronger and cheaper homes — and the climate benefits come with it.”

When he visits a town and sees hundreds of homes built with compressed earth blocks, Bjorn says he’s always amazed. “All we did was sell them a machine, and with their team they made it all happen. There’s nothing more inspiring.”

Looking ahead, Bjorn feels a real sense of urgency to implement the Build Up Nepal vision as quickly as possible. However, he is optimistic that they are “at a pivotal moment to really succeed.”