• From Oct. 2022 to Jan. 2023, 14Trees 3D printed 10 houses in Kilifi, Kenya, averaging one house per week
  • 6 three-bedrooms (76 m2 / 836 SF) and 4 two-bedrooms (56 m2 / 616 SF) houses have been 3D printed so far, making Mvule Gardens in Kilifi the largest 3D printed project to date
  • No other completed 3D construction printing project is currently larger than that, in the US or elsewhere
  • The fastest time to print one house in the Mvule Gardens project was 18 hours. See the video here: link
  • No other 3D construction printing project has matched 14Trees productivity, in the US or elsewhere

For a long time, 3D construction printing has been seen as a possible solution to the escalating affordable housing crisis. Proponents of the technology claim, that when 3D printing projects in construction are carried out at scale, the advantages of the technology become clear. Evidence of that claim has been lacking, but recent developments actually provide credibility to the statement.

14Trees is a joint venture company between the cement and concrete giant Holcim and British International Investment dedicated to accelerating the provision of affordable housing in Africa. The joint venture is behind the first 3D printed houses in Africa and the first 3D printed schools in the world. This week 14Trees announced some of the initial results of their efforts to 3D print up to 52 houses in Kilifi, Kenya, using a single BOD2 printer from COBOD. The BOD2 is the world’s best-selling construction 3D printer. Following the start in October 2022, 14Trees completed the 3D printing of the walls of 10 houses in January 2023 after just 10 weeks using only one printer.

In addition, the project’s sustainability profile also attained an EDGE Advanced sustainable design certification by IFC, the World Bank’s development finance institution, which recognizes resource-efficient buildings with the potential to be zero-carbon. It is the first time a 3D printed housing project has attained this certification.

Commenting on the achievements, Francois Perrot, Managing Director of 14Trees said:


“With 3D printing, you can solve two problems at once. You can build faster like we have shown here with our 10 houses in 10 weeks. At the same time, we can achieve better cost efficiency, which will help make affordable housing a reality for the majority. In addition, you can build with less materials, which preserves the resources of the planet for future generations.”


14Trees intends to get the full benefit of the large-scale project by experimenting and innovating as the project progresses. During the next phases which consist of 10-15 houses each, several innovations will be included that will allow future tenants to design their homes and move away from the standardized 3D printed approach to one which fully leverages the technology’s customization possibilities.

The cost of construction is also an area of focus. With each phase, 14Trees is aiming at lowering construction costs further such that the build cost is 20% lower than standard houses. Using Holcim’s proprietary 3D printing materials, TectorPrint, made at a local plant, has already meant a significant reduction in costs.

14Trees is not the only company busy with construction 3D printing projects of multiple housing units. Especially in the US several large-scale have been announced, including a venture-backed US-based construction 3D printing company’s 100 houses project, which attracted global media coverage when they began printing in early November 2022 (announced 2021) at a site where 5 or more identical printers were used simultaneously. As of early February, three months after the printing began, reports show that less than 9 houses had been printed so far. Commenting on the performance of 14Trees in relation to the developments in the US, Philip Lund-Nielsen, Head of COBOD Americas stated:


“Considering how difficult the conditions are in Africa, it is impressive, that 14Trees has printed more houses on a single site, than any other construction 3D printing company in the US or elsewhere. In addition, they have done it faster, using just a single COBOD 3D printer not by using 5 printers or more”.

Architects have warned that a government-funded drive to create new homes for rough sleepers, while welcome, will not solve homelessness

Around 2,400 homeless people are due to be rehoused through the government’s Single Homelessness Accommodation Programme (SHAP), which launched last September.

The homes, which must be completed within three years, will be provided through a bidding process at the local level. The total funding available is £270 million.

London mayor Sadiq Khan said he would find housing for 800 homeless people in the capital by 2025 thanks to a £70 million slice of the funding announced last month (24 January).

The homes will be delivered by registered providers working in partnership with local authorities and are expected to target 18-to-24-year-olds. It remains unclear what form they will take, and whether they will be modular or retrofitted existing buildings.

HTA Design partner Mike De’Ath said that although this initiative would help ‘transform’ the lives of London’s rough sleepers, it would not fix the wider issues of homelessness.

‘The industry needs to take a holistic approach to ensure these homes are delivered to transform people’s lives both in the short and long term,’ he said.

‘Ultimately though, tackling homelessness goes beyond housing delivery, and the provision of shelter isn’t a silver bullet. Government funding also needs to address the socioeconomic conditions that lead to homelessness.’

De’Ath highlighted youth homelessness charity Centrepoint’s work providing 35 modular homes in Peckham, which will house people previously sleeping on the street, as an example of how the industry could collaborate using off site construction methods to solve homelessness.

Levitt Bernstein director Jo McCafferty echoed De’Ath’s call for a solution to the housing crisis that was in turn leading to people becoming homeless. She called the latest housing programme ‘only a sticking plaster’.

McCafferty told the AJ: ‘We are all elbow deep in housing and regeneration projects, where viability is worsening on a daily basis, where planning processes are delayed, where stretched programmes are jeopardising the funding that does exist, despite the admirable efforts of City Hall.

‘All of these factors are rapidly slowing the delivery of social housing when people need it the most, when the cost of living is making access to good housing even less attainable for so many, and daily life is such a struggle.’

Heather Macey, of the Architects Aware! think tank, told the AJ that any new housing needed to be provided alongside new support services – particularly for young rough sleepers, whose numbers rose during the pandemic.

She told the AJ: ‘Youth homelessness is a complex problem which has been further exasperated during the pandemic.

‘Our research has shown that the emergency accommodation currently on offer to young people is substandard, often in poorly converted buildings, and frequently with no privacy, security or space for social support.’

Macey, whose think tank has called for unused buildings in London to be turned into homeless shelters, added: ‘Purpose-built emergency shelters for young people at risk of or suffering from homelessness are barely in existence at all.

‘A lack of design guidance around this area of housing provision – as well as almost no discernible clear policy to implement these types of projects – makes their delivery an uphill struggle.’

Following the announcement, the mayor of London said: ‘We can’t do this alone, and to end rough sleeping in our capital, particularly amid the cost of living crisis, the government must intervene to prevent the circumstances that lead to people sleeping rough before thousands more are forced to face a winter on the streets.’

Under the mayor’s announcement, capital funding will be made available for homes starting construction from April 2023 and completing before March 2025.


Jo McCafferty, director, Levitt Bernstein:

Whilst entirely endorsing the mayor’s much-needed increased funding for housing for rough sleepers, and the vital work of Crisis and St Mungo’s, the SHAP is only a sticking plaster to solve a broader housing problem across the capital. This is emergency funding for the most vulnerable, not a long-term solution. Ultimately, the basis of any broader and deeper answer to our housing problems must come down to the total quantum of state funding available for social housing and easy access to these funds.

This is only a sticking plaster

We are all elbow-deep in housing and regeneration projects, where viability is worsening on a daily basis, where planning processes are delayed, where stretched programmes are jeopardising the funding that does exist, despite the admirable efforts of City Hall. All of these factors are rapidly slowing the delivery of social housing when people need it the most, when the cost of living is making access to good housing even less attainable for so many, and daily life is such a struggle.

If I sound angry, it is because I am. Very. Invest in high-quality housing for all, as crucial, vital infrastructure, and the burden on our health, social care and education systems will dramatically reduce. It is a fact. We need a government that understands this and has the moral conscience to commit to a radical, nationwide social housing programme. It is that simple.


Source: Architects Journal