Interlocking blocks gain ground in new push for decent rural homes
Real Estate
By
Amos Kiarie
| Sep 03, 2026
Interlocking hollow concrete blocks are emerging as key alternatives to conventional stone construction, with housing developers saying the technology could reduce the materials, labour and time required to put up decent homes.
The blocks can be produced at construction sites using smaller quantities of cement and sand or quarry dust, potentially reducing some of the costs associated with transporting and handling conventional building materials, according to Habitat for Humanity Kenya.
In Muramati, Segera Ward, Habitat for Humanity Kenya is using the technology to construct homes for vulnerable families while combining housing improvements with water and sanitation infrastructure.
For 71-year-old widow Napeiyo Ngilekoi, the intervention comes after years of living with her three grandchildren in a deteriorating timber house that offers little protection from rain, cold and other elements.
When it rains, Napeiyo does not sleep comfortably. She moves her three grandchildren around the house in search of the remaining dry spots as water pours through the leaking iron-sheet roof.
The walls are loosely assembled from old timber off-cuts and patched corrugated iron sheets, while one window is covered with mosquito netting over wire mesh. The earthen floor further worsens the family's living conditions during the wet season.
Napeiyo is the primary caregiver for the three children. Two, both aged eight, are socially orphaned, while the third, 15-year-old Nicholus Nkirimoi, lives with epilepsy and requires regular clinic visits.
The family's limited income comes from occasional casual work when Napeiyo's health allows, support from neighbours, well-wishers and the local church, as well as a modest government stipend for older persons.
They also walk about one kilometre to fetch water, while sanitation is provided by a shallow makeshift pit latrine constructed from old iron sheets that is vulnerable to collapse and can overflow during heavy rains.
“I am very happy with the new house because when it rains, we no longer get rained on, and we now have a clean and safe toilet. Life will be much easier for me and my grandchildren,” she said.
Napeiyo's situation illustrates how inadequate housing can extend beyond the physical structure to water, sanitation and the ability of a household to maintain a safe living environment. It is this challenge that Habitat for Humanity Kenya says it is seeking to address through a combination of alternative construction technology and incremental housing.
Habitat construction supervisor Charles Misau said the interlocking hollow concrete blocks have a cavity that reduces the amount of concrete and other materials needed during construction.
“Because it's a hollow block, it means you're using very small quantities of construction material, that is sand and cement, or cement and quarry dust,” Misau said.
The reduction in material use, he said, can also be accompanied by lower labour requirements because the blocks are lightweight and easier to lay. “And the fact that it is a cavity wall, it's also lightweight, because it's very easy to lay, and use minimum labour force in constructing using the technology,” he said.
The technology could also shorten construction periods, an advantage for households and projects where labour costs increase with the length of time taken to complete a house.
Misau said builders could erect an entire wall in a day depending on the workforce available. “You can erect a whole wall in one day, depending on the labour force you have,” he said.
He contrasted this with conventional construction methods, where builders may have to wait between stages before proceeding.
“Traditionally, that will again lower the cost in terms of labour force, based on the time required to construct a house using this technology,” Misau said.
Another potential saving, according to Misau, comes from producing the blocks where they are needed. He said the technology could reduce the cost of transporting construction materials, particularly in rural areas where houses may be located far from suppliers.
“What saves a lot of costs here is that with this technology, you can produce the blocks on site, avoiding double handling and transportation costs,” he said.
The technology also makes use of quarry dust, which Misau said is available in areas with quarrying activity. “As Habitat, we are trying to take this to the village centre, because we find that in areas like where we are, there are a lot of quarry sites that have a lot of quarry dust as one of the products,” he said.
He said the material could be used to produce the blocks locally, allowing communities to avoid some of the expenses associated with transporting construction materials.
The technology is being applied in Muramati, where Habitat has already built eight houses and is constructing seven more for needy families.
But the organisation's approach goes beyond putting up new houses. Habitat for Humanity Kenya chairperson Rose Sang said the organisation was also focusing on incremental housing, where families improve their homes progressively rather than having to finance a complete house at once.
“It's also about incremental housing where we try to improve households so that then we have decent accommodation for everybody,” Sang said.
Incremental housing can allow families with limited resources to improve their homes in stages, potentially making housing upgrades more attainable for households that cannot raise the full construction cost at once.
Sang said housing could help reduce disparities among families by providing a basic foundation for children and households. “And what that does for us is that it equalises us through the use of housing,” Sang said.
The organisation's housing intervention is also being linked to water infrastructure, reflecting the view that a building cannot be considered adequate simply because it has walls and a roof.
National Director of Habitat for Humanity Kenya Dr Eileen Mokaya said the organisation had worked on housing and water projects in several counties during its 45 years of operation.
She said Habitat had worked on housing projects in more than 18 counties, with its main focus being vulnerable families who lack access to decent shelter. “The major focus is to ensure that the most vulnerable families do have access to what you can call a decent home,” she said.
“One of the other things that Habitat does is to ensure that when you say a home is decent, they also have access to basic services, especially when we talk about access to clean, safe water and also access to sanitation facilities,” she said.
“Our homes are never complete without sanitation facilities,” Mokaya said.
In Muramati, Habitat is drilling a solar-powered community borehole to improve access to water for the wider community. Mokaya said the borehole is part of the organisation's effort to address the infrastructure needs surrounding housing.
The programme is expected to support the construction of about 50 houses, according to Sang, who said the organisation wanted to continue working with communities to improve housing conditions.