Days of contractors misapropriating construction budgets, purchasing low quality building materials and taking too long to build a house are soon coming to an end in Kenya, thanks to 3D printing technology.

Casuals used to stealing building materials will also have nowhere to hide. The first 3D-printed housing project in Kenya is kicking off early 2022, implemented by 14Trees, a joint venture between Bamburi Cement’s parent company, Holcim and CDC Group.

The development is targeting first-time home buyers with the 3D-printed houses technology as the private sector explores avenues of supporting government’s ambitious housing project under the Big 4 agenda.

The State Department on Housing projects that at least 300,000 housing units are needed annually to meet the current housing demand, thus setting an ambitious Affordable Housing Project (AHP), which aims at delivering 500,000 units in five years.

The futuristic 3D printing and smart design will move the country towards this target since house completion is faster. A wall can be built in 12 hours compared to almost four days with conventional building techniques, while reducing the environmental footprint of a house by more than 50percent.

“The government has put in place a raft of incentives to facilitate the private sector to deliver affordable housing and seeing 3D printing technology take root in the construction space is a move in the right direction. First time home buyers have also been given incentives to take up units,” said Mr Charles Hinga, the PS in the State Department for Housing and Urban Development, who was speaking during the launch of the 3D printed show house at Bamburi Cement plant in Athi River.

Such incentives include tax relief of 15percent of savings or contribution savings towards homeownership and stamp duty exemptions for first-time buyers.

Developers get VAT exemptions on purchase of goods for the construction of houses under affordable housing, retention of Import Declaration Fee (IDF) at 2percent and Railway Development Levy (RDL) at 1.5percent for goods imported for construction of houses under the scheme and a lower corporate tax of 15percent for those constructing over 100 units.

The project pilot phase will produce a 52-house gated community complex in Kilifi which will be either one bedroom, two bedroom or three bedroom units at Ksh2.4 million, Ksh3.2million, Ksh 4.4million respectively.

The project will utilise Holcim’s proprietary ink, TectorPrint which Bamburi Cement will introduce in the market soon. The Tector range gives the 3D printed walls structural function, a breakthrough that will accelerate the scale-up of 3D printing for affordable housing

“As part of Bamburi’s commitment to supporting the Government of Kenya’s Big 4 Agenda on affordable housing, we are delighted to be supplying our innovative building materials for this truly ground-breaking project,” said Seddiq Hassani, the Managing Director of Bamburi Cement.

14Trees’ ability to provide a rapid and economical method of solving Africa’s housing deficit, which is estimated at 50 million units, will also help to create locally-based skilled jobs within sustainability and 3D technology, as well as other areas. 

The project has won the IFC-EDGE advanced sustainable design certification, which recognises resource-efficient and zero-carbon buildings, with construction starting in the first quarter of 2022.

“14Trees is pioneering the use of leading-edge technology to address one of Africa’s most pressing development needs – affordable housing – to create life-changing infrastructure for whole communities,” said Tenbite Ermias, Head of Africa and Africa Managing Director at CDC Group.

14Trees first embarked on its mission to build affordable and low-carbon housing and schools in Africa last year, starting with a prototype house in Lilongwe, and a school in Salima, Malawi. Completed in July in just 12 hours, the Salima school is reportedly the world’s first 3D printed school and has already welcomed students through its doors. 

The project was rolled out to Zimbabwe earlier this year to address the country’s chronic housing and infrastructure shortage and to showcase the capabilities of 3D printing for construction. 

By 2025, Dubai plans for a fourth of its buildings to be printed in 3D construction methods, demonstrating the potential of a fast-growing technology capable of redefining and pushing the limits of traditional architecture.

As the technique emerges as a viable solution in the construction, engineering, and architecture areas, its popularity is quickly increasing. In fact, just between 2021 and 2028, the global 3D construction market is expected to grow by 91percent, according to a July 2021 report by Grand View Research.

Why this rapid growth? Besides being a faster alternative and having lower construction costs, it can also provide affordable housing solutions and allow countless design possibilities, among many other benefits.

Thus, as architects must adapt to a new technological era, where speed and efficiency have become key factors in design and execution processes, the rise of 3D printing shows enormous promise. It could even help reshape construction as we know it.

How does 3D printing work?

Even though the 3D construction printing technology is currently at an early stage, PERI, one of the world’s leading suppliers of formwork and scaffold systems, has been heavily involved in the market for several years now.

Together with Danish company COBOD, the German family-owned company has been working to refine the technology and open up to new markets. The focus is primarily on residential construction, but also includes production of individual prefabricated components.

PERI uses a machine known as the COBOD BOD2, a fully developed and safe 3D construction printer that can be configured in any direction for a wide range of applications, whether it be walls, columns, stairs, or other building elements.

Each COBOD BOD2 offers numerous advantages, such as a portal system suitable for off-site production and in-situ application, eliminating the need for frequent relocation and calibration. At the same time, the system comprises a number of modules which can be chosen to fit specific projects. 

The printer, however, particularly stands out because of its speed compared to other machines. Besides being the fastest construction printer on the market with a maximum speed of 1m/s, it has been certified in a way that it is possible to carry out work within the printing area while printing is in progress.

Therefore, all sorts of manual work, such as pipe installation, can be easily integrated and thus optimize the building process.  

Even though ceilings, floor slabs, and foundations are constructed in a traditional manner, the BOD2 has proven it can successfully produce concrete walls. After the printer is transported to the construction site, the Z-axes are installed, the print head is attached to the X-axis of the steel structure, and a commercially available silo and concrete pump are connected to the BOD2. With the assembly complete, the printing process operates in three dimensions along the 3 axes on a secured metallic frame. 

As the printed cavity wall meets the static requirements in residential buildings, no reinforcement is required. In addition, the printed double-skin cavity walls can integrate insulation methods in any way.

Besides positioning PERI as a pioneer in the market, the success of the one-of-a-kind project proves that 3D construction is viable and opens a whole range of possibilities in the industry.

It also set the stage for larger and more complex dwelling units. Precisely two months after work started on the house in Beckum, PERI set out to print the largest printed apartment building in Europe, this time in Wallenhausen, Bavaria.

Distributed in 3 floors and 380 sqm, 4 out of 5 units are rented out, while one of them is used as a show apartment. Since then, much of what was initially learned in Beckum has also been incorporated into the first residential project in Tempe, Arizona, an apartment building extension at the Lake of Constance in Germany, and the first 3D-printed building in Austria executed in cooperation with STRABAG SE.