Feasibility study of accommodations along the Great Green Wall in Africa

Due to our extensive knowledge of sustainable and innovative building methods – such as 3D concrete printing (3DCP) – Witteveen+Bos was asked by UNODC in mid-2021 to conduct a feasibility study into 3DCP as a construction method for affordable housing along the Great Green Wall in Africa.

UNODC, the United Nations Office on Drugs and Crime, is planning to build 500 affordable homes (40-70 m²) as a pilot for employees involved in the construction of the Great Green Wall. Afterwards, the homes can be used by the local population. UNODC collaborates closely with the private sector on realising affordable housing in Africa. 3D concrete printing has been identified as one of the most appealing technologies for sustainable, innovative and cost-efficient construction. Nowadays it is available on a much larger scale than in the past, and numerous companies are working on 3DCP technology and projects. For this reason, the first step involved investigating the feasibility of using 3DCP as a construction method for this project, compared with four other potential innovative construction methods.

The feasibility of each method was analysed in terms of materials, labour, technologies and costs. The study also addressed the needs of an autonomous village in terms of drinking water, energy and waste water. Guidelines were provided for selecting a location. These included the surface area of the development, topographical constraints, and potential regions in Africa. The study showed that 3DCP is an appealing technology for the development of affordable homes. The importance of developing printing materials based on local raw and waste materials, both in terms of sustainability and affordability, was also highlighted.

Witteveen+Bos is currently working on identifying these raw and waste materials and investigating alternative sustainable concrete mixes, in collaboration with research institutes and local partners.