Earth blocks keep homes cool while cutting emissions in Kenya’s drylands
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In Kenya’s Laikipia County where temperatures can reach as high as 30 degrees Celsius, a local building technology is helping homes stay cooler while supporting education, creating jobs and improving the livelihoods and resilience of community residents, Climate Home News found on a visit to the region.
Situated in a semi-arid region, houses in Laikipia are mostly built with wood or cement blocks with corrugated iron sheets for roofing. This building method usually leaves the insides of homes scorching hot – and as global warming accelerates, the heat is becoming unbearable.
Peter Muthui, principal of Mukima Secondary School in Laikipia County, lived in these harsh conditions until 2023, when the Laikipia Integrated Housing Project began in his community.
The project uses compressed earth block (CEB) technology, drawing on traditional building methods and local materials – including soil, timber, grass and cow dung – to keep buildings cool in the highland climate. The thick earth walls provide insulation against the heat.
Peter Muthui, principal of Mukima Secondary School in Laikipia County, stands in front of classroom blocks built with compressed earth blocks (Photo: Vivian Chime)
Peter Muthui, principal of Mukima Secondary School in Laikipia County, stands in front of classroom blocks built with compressed earth blocks (Photo: Vivian Chime)
“Especially around the months of September all the way to December, it is very, very hot [in Laikipia], but as you might have noticed, my house is very cool even during the heat,” Muthui told Climate Home News.
His school has also deployed the technology for classrooms and boarding hostels to ensure students can carry on studying during the hottest seasons of the year. This way, they are protected from severe conditions and school closures can be avoided. In South Sudan, dozens of students collapsed from heat stroke in the capital Juba earlier this year, causing the country to shutter schools for weeks.
COP30 sees first action call on sustainable, affordable housing
The buildings and construction sector accounts for 37% of global emissions, making it the world’s largest emitter of greenhouse gases, according to the UN Environment Programme (UNEP). While calls to decarbonise the sector have grown, meaningful action to cut emissions has remained limited.
At COP28 in Dubai, the United Arab Emirates and Canada launched the Cement and Concrete Breakthrough Initiative to speed up investment in the technologies, policies and tools needed to put the cement and concrete industry on a net zero-emissions path by 2050.
Canada’s innovation minister, François-Philippe Champagne, said the initiative aimed to build a competitive “green cement and concrete industry” which creates jobs while building a cleaner future.
Coordinated by UNEP’s Global Alliance for Buildings and Construction, the council has urged countries to embed climate considerations into affordable housing from the outset, “ensuring the drive to deliver adequate homes for social inclusion goes hand in hand with minimising whole-life emissions and environmental impacts”.
Homes built with compressed earth blocks in Laikipia (Photo: Julián Reingold)
Homes built with compressed earth blocks in Laikipia (Photo: Julián Reingold)
With buildings responsible for 34% of energy-related emissions and 32% of global energy demand, and 2.8 billion people living in inadequate housing, the ICBC stressed that “affordable, adequate, resource-efficient, low-carbon, climate-resilient and durable housing is essential to a just transition, the achievement of the Sustainable Development Goals and the effective implementation of the Paris Agreement”.
Compressed earth offers local, green alternative
By using locally sourced materials, and just a little bit of cement, the compressed earth technology is helping residents in Kenya’s Laikipia region to build affordable, climate-smart homes that reduce emissions and environmental impacts while creating economic opportunities for local residents, said Dacan Aballa, construction manager at Habitat for Humanity International, the project’s developers.
Aballa said carbon emissions in the construction sector occur all through the lifecycle, from material extraction, processing and transportation to usage and end of life. However, by switching to compressed earth blocks, residents can source materials available in their environment, avoiding nearly all of that embedded carbon pollution.
According to the World Economic Forum (WEF), global cement manufacturing is responsible for about 8% of total CO2 emissions, and the current trajectory would see emissions from the sector soar to 3.8 billion tonnes per year by 2050 – a level that, compared to countries, would place the cement industry as one of the world’s top three or four emitters alongside the US and China.
Comparing compressed earth blocks and conventional materials in terms of carbon emissions, Aballa said that by using soil native to the area, the process avoids the fossil fuels that would normally have been used for to produce and transport building materials, slashing carbon and nitrogen dioxide emissions.
The local building technology also helps save on energy that would have been used for cooling these houses as well as keeping them warm during colder periods, Aballa explained.
Justin Atemi, water and sanitation officer at Habitat for Humanity, said the brick-making technique helps reduce deforestation too. This is because the blocks are left to air dry under the sun for 21 days – as opposed to conventional fired-clay blocks that use wood as fuel for kilns – and are then ready for use.
Women walk passed houses in the village of Kangimi, Kaduna State, Nigeria (Photo: Sadiq Mustapha)
Traditional knowledge becomes adaptation mechanism
Africa’s red clay soil was long used as a building material for homes, before cement blocks and concrete became common. However, the method never fully disappeared. Now, as climate change brings higher temperatures, this traditional building approach is gaining renewed attention, especially in low-income communities in arid and semi-arid regions struggling to cope with extreme heat.
From Kenya’s highlands to Senegal’s Sahelian cities, compressed earth construction is being repurposed as a low-cost, eco-friendly option for homes, schools, hospitals – and even multi-storey buildings.
Museum of West African Art (MOWAA), Benin City, Nigeria. Photo: MOWAA X page
Museum of West African Art (MOWAA), Benin City, Nigeria. Photo: MOWAA X page
Senegal’s Goethe-Institut in Dakar was constructed primarily using compressed earth blocks. In Mali, the Bamako medical school, which was built with unfired mud bricks, stays cool even during the hottest weather.
And more recently, in Nigeria’s cultural city of Benin, the just-finished Museum of West African Art (MOWA) was built using “rammed earth” architecture – a similar technology that compresses moist soil into wooden frames to form solid walls – making it one of the largest such structures in Africa.