Construction Technologies and Materials for Sustainable Affordable Housing

This scarcity and precariousness is comparable to housing conditions in slums or refugee camps. In particular, according to Bonnet et al. (2020): “In 2017, over 480 of these settlements were spread across Mogadishu. Most of them are located in the northwestern part (e.g. Hodan and Daynile Districts), though there are also some in the centre (e.g. Shangani) and southwest (e.g. Kaxda). Living conditions in these settlements are dire. Housing consists predominantly of corrugated metal sheet shacks or so-called bulls, temporary shelters made of sticks, plastic and fabric” (Bonnet et al. 2020).

The Triple Bottom Line (TBL) of People, Planet and Profit, term coined by Elkington in 1997 (Loviscek 2020), is currently a widespread method that encompasses social, environmental and economic aspects, supporting the set up of long-term strategies for companies (Correia 2019). The transition toward sustainability is, indeed, based on three important dimensions of the sustainable development (Loviscek 2020): environmental quality, social equity and economic benefits (Correia 2019).

Finishing components and furniture, together with structural elements, play a significant role in the definition of the final selling price of the building, having a high economic impact on the costs in overall terms (Atta et al. 2021).

The process of analysing of the technological solutions currently used in the construction practice in Mogadishu has been based on a strong interaction with local stakeholders. Interviews, questionnaires, and focus-groups with local construction companies and professionals in the field have been carried out in order to gain insights on construction processes and technologies, with particular reference to the commonly used products and materials, supply chain configurations, building site organization, construction machineries and employed workforce. Moreover, the performed analysis was also supported by documents provided by the interviewed companies, including pictures of construction phases and construction techniques, bills of quantities and cost estimations.

In particular, the OmniClass “Construction Classification System” (ICS 2021) is adopted to define a common taxonomy, a hierarchical structure and a coding system useful to uniquely identify the set of building components, thus creating a reference framework able to describe in a clear and unambiguous way by using a shared language the technological solutions constituting a building asset. Particularly, the OmniClass system consists of a set of inter-related tables, not meant to be utilized all at once but allowing the selection of the ones more significant for the purposes of the analysis. In this way, it enables the creation of ad-hoc Product Breakdown Structure (PBS) (ICS 2021), tailored to the specific case. Moreover, the standard is particularly instrumental as it employs the nomenclature commonly used in construction practice within digital tools such as Building Information Modeling (BIM), providing a standardized basis for classifying information created and used by the Architectural, Engineering, and Construction (AEC) industry. In particular, the proposed hierarchical framework of building classification based on OmniClass is created by combining three different OmniClass Tables, i.e., Elements (Table 21), Products (Table 23) and Materials (Table 41).

The alternative technologies identified in Table 2 are characterized by three levels (low-medium-high) which differ in terms of innovation, of both materials and construction processes compared to current practices. It is important to stress that while identifying alternative solutions for the specific application context of Mogadishu, it is necessary to consider the related underlying implications, both in procedural and organizational terms (including logistic, production, supply chain, training, timing, etc.).

The propose tool can be integrated within an IT system or developed as a simplified Excel file, according to the level of complexity and digital maturity of the particular context of application.