The high costs of land, bulk infrastructure, and housing construction have made it very difficult and often impossible to provide affordable housing for the majority of middle-income and low-income households. Even though, the shortage of affordable housing is not specific to Africa, it has reached a critical level on the continent. It is clear therefore that finding ways to lower construction costs is imperative to meet the affordable housing demand.
This chapter explores several avenues for delivering affordable housing developments while reducing construction costs and house prices in Africa, including the following: (1) industrialized construction, (2) reducing waste of building materials, (3) process improvements to improve efficiency, (4) local production of building materials, (5) use of alternative building technologies, (6) densification, and (7) capacity building and skills training. This is consistent with the findings of the McKinsey Global Institute (Woetzel et al. 2014) report, which, in a global study addressing affordable housing issues, identified four levers that can narrow the affordability gapFootnote 4 by up to 48 percent. These include unlocking land supply, taking an industrial approach, achieving scale efficiency for operations and maintenance, and reducing the costs of and expanding access to finance.
5.5.1 Industrialized Construction
In order to fill the affordable housing deficit of more than 51 million units and deliver large-scale housing developments, Africa’s construction sector needs to undergo an extensive transformation toward industrialization. Industrialization of the housing construction process is often mentioned as a way to cut costs, reduce the time of construction, and produce mass housing. It was used in Europe and the United States after World War II with various degrees of success. For instance, the US Housing Act of 1949 set a goal to construct 810,000 units in six years using industrialized methods; however, owing to political opposition to public housing and racial integration, the program was not very successful, as it reached its goal only in 1969 (Von Hoffman 2000).
5.5.1.1 Industrialized Construction: What Is It?
Industrialization of housing construction involves the use of prefabricated parts, manufactured in plants outside the project site, which are then assembled on-site. The objective of the approach is to save time and costs and to achieve gains in productivity (both capital and labor). Productivity in the construction industry is relatively low and has been falling in both developed and developing countries. The MGI report notes that between 1989 and 2009, while overall labor productivity in the United States increased by a third, in the construction sector it fell by a fifth. Bailey and Solow (2001) note that the economies of scale achieved through large housing developments in the United States and the Netherlands are important in explaining their superior productivity compared with other European countries, where small plots of land are allocated to housing projects. They also note that gaps in scale and managerial abilities explain the difference in labor productivity between the United States and Brazil.
Conventional construction methods that are labor intensive and in which most components are made on-site, often involving a lot of specialization, lead to long construction times and high costs. An estimated 33.4 percent of time is wasted in construction sites in Sweden, for example (Josephson and Saukkoripii 2007). A large share of this wasted time involves reworking, waiting, handling interruptions, and inaction. Preparation time also represents a large share—45.4 percent—of the total working time, whereas value adding time represents only 17.5 percent. Conventional methods also lead to material waste, as manufactured materials often need to be cut to fit the customized sizes. Another source of low productivity is the dominance of SMEs with low capital equipment and financial capacity. For instance, of the 163,000 companies registered in the United Kingdom in 1998, the majority employed fewer than eight workers (Construction Task Force 1998). Moreover, the firms retain very few skilled workers, as time between projects varies widely. It is argued in this book that adopting an industrial approach would go a long way to addressing the above-mentioned issues.
5.5.1.2 Is Industrialized Construction the Right Approach for Africa?
The public view of industrialized construction is limited to the use of precast components or systems. However, it is our conviction that it goes beyond that, although there is no consensus on its definition. There is not a unique way of defining or conceptualizing industrialization in the construction sector, and the use of prefabrication ranges from simple structures to complete houses. The definition depends on the objective and whether authors are considering either the process or the product (Zabihi et al. 2012). There is also a large variation in the extent of prefabrication. The objectives and experiences of such industrialization also differ by country. For instance, the definition of the US Department of Housing and Urban Development covers the range from prefabricated components or modules up to complete homes, such as mobile homes. In the United States, prefabrication has not taken off, due partly to geographic barriers and availability of low-cost migrant workers. In Malaysia, the use of industrialized building systems has failed to achieve the government’s targets despite its implementation of encouraging policies (Chan 2011). In some developed countries, the goal of industrialization is to substitute high-cost labor with capital by increasing the usage of automation and equipment. Obviously, this may not be the type of industrialization one would like to experience in Africa, bearing in mind the need for the continent to take advantage of the demographic dividend while addressing the large youth unemployment. In fact, one of the key developmental challenges of African countries today is how to create jobs for the large shares of unemployed or underemployed youth populations and thus improve the livelihood of African people. This calls for housing construction policies that are biased toward more labor-intensive technologies. Prefabrication of complex structures using automation is thus not a viable option for Africa.
The goal of industrialized construction in Africa could consist in producing at massive scale, in shorter periods of time, at lower costs, while taking into account the countries stage of development and peculiarities, including features such as an abundance of unskilled labor and a shortage of capital. In so doing, it is important to ensure that housing and construction policies are integral parts of the country’s development policy agenda.
Taking a value chain approach will improve the productivity of the sector and its ability to deliver affordable housing at scale. Moreover, given the role played by SMEs in African economies and their strong presence in the construction sector, industrialization of construction should be seen as a business opportunity for SMEs. In fact, the range of prefabricated materials is large, and simple structures can be made by SMEs with less capital intensity. Using simple and less bulky components makes installation less capital and skill intensive, and therefore could be delivered by SMEs. Indeed, complex components require high skills for installation. In Sweden, some prefabrication companies have failed because they created systems that require low tolerance in the installation process (Malmgren 2014).
A successful example of a labor-intensive construction method using prefabricated materials can be seen in Ethiopia. The first phase of the Ethiopian IUHDP trained and equipped MSEs to prefabricate a number of components and supply some materials such as aggregates. As a result, from 2000 to 2006, some 2600 MSEs employing 49,000 workers were created. The MSEs were involved in production activities for a variety of materials: aggregate, precast beams, hybrid composite beams, metal and wood, stone, etc. As the volume of construction increased under phase 2, the number of MSEs involved in prefabrication also increased. Phase 2 created 561,856 jobs and built 192,467 housing units between 2010 and January 2015 (see Box 5.1).
The following subsections describe the steps that are necessary in the industrialization process of the construction sector.
5.5.1.3 What Does It Take? Standardization is Key
Prefabrication or precasting of components such as doors, windows, and sanitary elements is already part of housing construction in Africa. However, the lack of standardized dimensions may prevent the production of these components at large scale. For instance, in self-built housing, each house has its own dimensions for the doors and windows, which are then built to order by carpenters. Moreover, housing superstructures are largely built using blocks that are made on-site or purchased from block molders. Therefore, laying brick for external and internal walls takes a large share of time in the building process. This time and the resulting costs can be cut by using prefabricated concrete or other types of panels. Examples in India, Mexico, and South Africa show time savings of 40–50 percent (MGI 2014). However, savings vary widely, from 10 percent to above 50 percent (Malmgren 2014). In South Africa, the use of precast concrete and optimized design has permitted overall cost savings of 25 percent for an affordable housing project (MGI 2014). The cost savings come from shorter project completion periods, which translate into lower labor and financing costs as well as to lower wastage of building materials. In addition to the time and cost savings, the quality of the superstructure can be increased as the concrete is not exposed to the natural environment and as adequate mixes of cement and aggregates are applied. This consideration is especially important during certain seasons, such as winter in temperate areas and the rainy season in tropical countries.
Prefabrication does not benefit only the superstructure and finishing elements; roofing can also benefit. In difficult working conditions, the roof is generally time consuming and costly. In Kenya’s self-built housing, roofing costs constitute nearly 50 percent of the total building costs. Roofing is ranked first in terms of the building stage that exerts the most financial pressure on self-built housing for low-income households. Often, roofing expenses dictate the size of rooms at the design stage.Footnote 5 Time and costs can be cut significantly using prefabricated roofing components. In the Republic of Guinea, as in most African countries, most of the affordable houses are roofed using corrugated iron sheets. In the past, the sheets were sold in small sizes, requiring a long time to install and the use of a large number of nails. However, it is noted that new producers of these materials in the market offer customized, longer sheets. This reduces the time and costs of roofing while offering higher quality.
For precast concrete to be a competitive alternative to on-site building, the most important requirements for efficient industrial production are standardization, large scale, and good logistics. Standardized sizes and higher-quality components facilitate large-scale production by component manufacturers and decrease the complexity of building processes. They provide the economies of scale necessary to justify large capital investments. Standardization also allows savings in the sense that it provides an opportunity to combine orders and make large-volume purchases. The Ethiopian Integrated Urban Housing Program, for example, uses bulk purchases to reduce the cost of materials.
Standardized component sizes, quality of building materials, and building codes are important not only within countries but also within regional blocs. For instance, an aluminum window manufacturer from Sénégal will not benefit from economies of scale in exporting its products to the Republic of Guinea if window sizes in the two countries are different. As some regions become increasingly more integrated, it is important to set common standards to enable the creation and growth of regional component manufacturers. In other words, industrializing the construction sector should be seen in a wider perspective of regional integration, if one is concerned with benefiting from economies of scale.
It is important to note that some precast components such as standard concrete panels, which are heavy and costly to transport, require high demand in a relatively small area. Clogged roads in poor condition across the continent constitute a significant constraint, which make the establishment of adequate logistics an important prerequisite for precast concrete. If components cannot be delivered on time and at competitive prices, the industrialized approach will not deliver on its goals to save time and costs.
Standardization should be introduced early in the process, at the design stage. Architects need to use available standard sizes in their designs in order to avoid multiple changes during construction (MGI 2014). A value chain approach, in which there is close coordination between designers, component suppliers, transporters, and construction companies, is therefore essential (Construction Task Force 1998). Box 5.2 shows how design, prefabrication, and good supply chain management have been used to reduce construction costs in Angola. It appears also from Box 5.2 that the model of Kora Housing is labor intensive at the assembly phase and required basic skills, which favored the employment of local labor, even in rural areas.
Box 5.2 Kora Housing: Lowering Costs Through Industrialized Construction
Kora Housing is building 40,000 housing units on 16 sites throughout nine provinces in Angola. It provides quality, affordable housing in community settings for the large and growing middle class emerging in Angola, thereby tackling the country’s housing shortage, which is estimated at about 2 million units. From March 2012 to June 2014, the company built and sold 15,206 units to Angola’s National Housing Fund. It is now well engaged in phase II of the project, which is to develop the next 7500 units.
The concept behind Kora Housing is to adapt construction systems and materials used for the development of urban communities to local reality and needs. To this end, the company developed comprehensive know-how about industrialized construction systems using prefabricated panels of autoclaved, aerated concrete—lightweight concrete panels that incorporate air. These panels, imported from Europe, are green materials that meet European Union standards; they are available in numerous shapes and sizes, allowing for a wide range of construction applications for all types of buildings. Implementation of projects starts with urban planning, including social infrastructure and housing designs, adapted to the local environment. The construction is executed by subcontractors but managed by Kora. The success factors leading to large-scale delivery and lower costs are the following:
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Design: Housing designs enable the standardization of elements and easy supply chain management, with close relationships between the design and supply chain management teams.
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Supply chain management: Kora manages the entire supply chain, from acquisition, transportation, and distribution to subcontractors. Purchasing is done in high volume through offtake agreements with material manufacturers and bulk agreements with transportation entities.
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Technology: The light weight of the concrete panels requires only small transport equipment; hence, the mobilization and initiation costs of contractors are very low. The technology also allows contractors to work with unskilled local workers who can be trained on-site.
The results of this construction system are 30 percent savings in construction costs and about 40 percent savings in time. Even though it works in remote provinces, Kora Housing is thus able to sell a house at 50–60 percent of market price. Moreover, despite the industrialized approach of the construction system, it is labor intensive; for instance, upon completion, the project is expected to have created 35,000 local jobs (9000 direct and 26,000 indirect).
Source: Based on Kora Housing Process document.
5.5.2 Process Improvement to Increase Efficiency
The low productivity in construction is related not only to the fact that production takes place on-site but also to how the production is organized. Poor project scheduling, with excessive sequencing of tasks, and poor management are important determinants of low productivity. Often, projects are executed the same way they have always been, with no effort to improve processes. The adoption of an industrial approach involves learning from process innovations in other industries and adapting them to the needs of the construction industry. Case in point is lean manufacturing and just-in-time production, which have been introduced in other industries with great success. For instance, rigorous project management and implementing techniques such as flowcharts showing all activities on a critical path to completion can reduce project completion times by making optimal use of the resources to perform some of the tasks simultaneously. The flowchart can also be used to make a better estimate of the demand for resources and to serve as a basis for a critical review of tasks. Such a review can lead to optimized processes that can be documented in an operational manual for employee training. Optimized and documented processes can also reduce rework, which is prevalent in construction projects. It is estimated that in developed countries, about 30 percent of the time spent on construction is used for rework (Construction Task Force 1998, Josephson and Saukkoriipi 2007).
Although consultants can be used to analyze and improve processes, construction managers are required to have good project management skills and to execute projects on time with the required quality level. However, during our fact-finding missions in Angola, Cameroon, Côte d’Ivoire, Ethiopia, Kenya, and South Africa, the shortage of managerial skills was often cited as a big constraint for scaling up affordable housing delivery. The Ethiopian government, with assistance from GIZ, undertook a capacity-building program to address this issue and other types of skills shortages. Although the situation has improved over the years, this skill shortage is still seen as a constraint in the sector.
5.5.3 Reducing Waste of Building Materials
Waste is a common feature in construction projects in both developed and developing countries. The two main types of waste are time and building materials, both contributing to cost overruns. We have already discussed the contribution of time wastage to the low productivity in the sector. Numerous studies have shown that in developed countries at least 10 percent of the costs of building materials are wasted in construction projects (Egan 1998). In Brazil, the wastage is estimated at about 20–25 percent (Bossink and Bouwers 1996). The extent of wastage of building materials in construction projects in Africa is not widely known but anecdotal evidence points to high shares of the total purchased. John and Itodo (2013) found that wastage contributes on average to 21–30 percent of project cost overruns in Nigeria, depending on the type of subcontracting arrangement. Using a case study in River State, Nigeria, Adewuli, and Otali (2013) show that the main factors contributing to the high levels of wastage are poor supervision, material handling, rework contrary to drawings and specifications, design changes, as well as revision and waste from uneconomical shapes. Similar studies conducted in other countries point to the same conclusion (Alwi et al. 2002, for instance, in Indonesia).
Given that material costs represent an estimated 50 percent of the overall costs of housing construction in most countries, it is clear that reducing waste will have a large impact on house prices. As discussed above, construction costs could be significantly curtailed by minimizing building material waste. In so doing, it is important that countries’ rules and regulations related to the standard measures of building materials are enforced. Recognizing this as a major issue, the IUHDP in Ethiopia created an incentive scheme for contractors to minimize waste: the contractor gets 50 percent of the cost of saved materials exceeding the 10 percent agreed level. In addition to cost considerations, construction waste has environmental costs, as its bulky nature means that it occupies space in landfills. Cement is well known as a nonenvironmentally friendly product, its production, manipulation, and use in construction projects do not always comply with the required standards. The waste related to its production and use could entail nonnegligible public health and biodiversity degradation consequences, which can turn up to be fairly costly. The share of construction waste in total solid waste represents 20–30 percent in Australia, 13–15 percent in Finland, 19 percent in Germany, 26 percent in the Netherlands, and 20–29 percent in the United States (Bossink and Bouwers 1996). To the best of our knowledge, reliable estimates for Africa are not available. Moreover, there are indirect environmental costs as energy is used for the production and transport of materials that are later wasted.
5.5.4 Local Production of Building Materials
In recent years, the discussion of structural transformation in Africa has highlighted the pattern of labor moving from agriculture into low-productive services (Bah 2011, AfDB et al. 2015). What is more, sub-Saharan Africa has been deindustrializing as the contribution of manufacturing to output has declined in several countries, representing on average just 11 percent of output today (AfDB et al. 2015). It has been argued that this pattern of structural transformation leads to low overall productivity and undermines Africa’s long-term development (McMillan and Rodrik 2011).
The need for Africa to undergo substantive structural transformation, which promotes industrialization has become an argument on which most development partners, such as the AfDB, have agreed upon. Moreover, policymakers and analysts are more or less convinced that industrialization should be high in country development policies and strategies. Recent reports from the United Nations Economic Commission on Africa (UNECA) have focused on how Africa can industrialize through trade, by leveraging its commodities (UNECA 2013, 2015). Manufacturing is seen as a catalyst for job creation and economic diversification (UNECA 2015).
In this book, it is argued that housing development in general, and the production of building materials, in particular, can be a channel through which countries could spearhead their industrialization. Producing building materials in Africa will not only create local jobs but also reduce construction costs. As discussed above, the demand for housing and infrastructure are fueling high demand for building materials, such as cement, steel, and finishing products, but this demand is essentially satisfied through imports, mostly from Asia. Interviews conducted during our fact-finding missions indicated that imports of building materials are an important driver of high construction costs, and this is likely to worsen in the near future due to large infrastructure investment programs on the continent. The effects of imports of building materials on construction costs are even more important in landlocked countries. For instance, it is estimated that transport costs represent 40 percent of building materials costs in Kigali, Rwanda.
This section analyzes the extent to which imports of building materials contribute to higher construction costs. Given the lack of data on the amount of building materials used, it is not possible to calculate the share of imports. Moreover, data on construction costs are available for only 27 countries, thereby making it more difficult to apply regression analysis. However, the available data do show that each of the six countries where we conducted fact-finding missions spent about US$400 million in 2014 for imports of building materials, supporting the view of stakeholders according to which imports are the main factor explaining the high costs of construction. Figure 5.8 shows that imports and construction costs are positively correlated, with a correlation coefficient of 0.15, even without including large importers such as Angola and Libya in the calculation. This suggests therefore that import substitution strategies could play a significant role in reducing the costs of construction (Box 5.3).
Box 5.3 Positive Effects of the Liberalization of the Cement Industry on Costs in Ethiopia
Until the mid-2000s, only government enterprises could supply cement in Ethiopia. These government factories had a combined capacity of 1.89 million tons per year, which have not been sufficient to meet the increasing demand since 2004. During the period of 2004–2006, the price of cement varied between US$249 and US$299 per ton.
In its ongoing efforts to upgrade and expand its infrastructure and housing supply, the government opened the cement market to private investors. As of November 2014, 11 cement factories operated in the country with a combined capacity of over 13 million tons, to supply a total demand estimated at 7 million tons. This excess supply has resulted in a sharp decline in cement prices, by over 50 percent. Today, a ton of cement costs between US$110 and US$124. For instance, Derba-produced cement is 20 percent cheaper than government-produced cement, which reduces the overall cost of construction by about 5 percent, according to Derba’s chief executive officer.
The opening of the cement market has also brought in the diversity in the cement grades accessible to customers. Derba recently completed a study of low-cost cement that can be used for flooring, wall plastering, fence construction, and the like. It expects to start producing this grade of cement shortly. The company also plans to sell ready-mix concrete in the future. Today, Derba delivers cement directly to all its retailers in Ethiopia using its fleet of 1000 trucks. Some 80 percent of Derba’s customers, about 600 retailers, are located within 400 km of its plant, which facilitates the transportation process. In Addis Ababa, a 50 kg bag of Derba cement costs US$10.40, with transport costs accounting for US$0.62 per bag of cement. Based on this business model, the retailer’s profit margin is about US$0.25 per bag of cement.
With an excess supply of about 6 million tons of cement, Ethiopia now exports to neighboring countries such as Kenya, South Sudan, and Djibouti. Derba dominates the northern Kenya cement market, with exports of 500,000 tons of cement per month since January 2014. However, Derba has encountered a few challenges in its Kenya expansion strategy. In October 2014, the Kenyan government eliminated the tax-free regime on imported cement and levied a 5 percent surtax on all imports. Moreover, unlike South Sudan and Djibouti, which allow Derba’s trucks to deliver cement to its final destination, Kenya does not permit Ethiopian trucks to enter its territory. Cement trucks are required to unload at the border and load the cement bags on Kenyan trucks. The loading and unloading creates delays, which raises the firm’s transportation costs. Factoring in the 5 percent surtax, the price for Derba’s imported cement is less competitive in cities such as Nairobi. Derba’s CEO expects that the ongoing effort to harmonize and standardize customs regulations in the East African Community will facilitate trade across member countries.
Source: Based on an October 2014 meeting with the CEO of Derba Cement.
The rise in local private-sector production of cement in various countries following the opening of the cement market confirms, at some extent, the observation that high imports as well as monopolistic behaviors contribute to high construction costs. For instance, cement prices in Ethiopia have been reduced by more than half as local production increased (Box 5.3). In Zambia, cement prices dropped by 40 percent between 2014 and 2015, following the opening of the Dangote Cement factory. This prompted accusations that Lafarge had been exploiting its monopoly position in the country (CAHF 2015). In Cameroon, the new Dangote plant commissioned in August 2015 led to a swift decline in cement prices of 15 percent in less than a month. Prices were expected to decline further following the opening of another production plant by Ciments d’Afrique, which would increase the firm’s installed capacity from 1.6 mtpa in 2014 to 4.2 mtpa. In Tanzania, cement prices were expected to decline by half after the commissioning of a 3 mtpa plant by Dangote in October 2015. This evidence supports the argument according to which African countries can make progress toward lowering construction costs by increasing local production of building materials.
Ethiopia and Rwanda are two countries that are undertaking import substitution strategies in the construction materials sector. As discussed earlier, Ethiopia increased its cement production more than sixfold and expects to increase its installed capacity and utilization rates. It is also promoting investments for steel and finishing products. Rwanda, with a growing construction sector worth over US$500 million, is also promoting investments in the manufacturing of building materials. The Rwandan Development Board (RDB), an investment promotion agency, is promoting investments in steel products, construction glass, and clay materials such as tiles and blocks. In 2011, more than 51 percent of the investment in manufacturing was directed toward the construction materials sector. The RDB expects a further US$204 million worth of investments in this sector in the coming years (Fig. 5.9).
5.5.5 Densification for Lower Costs of Urban Infrastructure and Sustainable Cities
Urban sprawl is costly to countries in all stages of development. A report by the Global Commission on the Climate and the Economy estimates that urban sprawl costs the US economy more than US$1 trillion per year (Todd 2015). Two direct consequences of urban sprawl are per capita land development and dispersed activities. The secondary impacts are reduced farmland, reduced natural lands, reduced accessibility, higher costs to provide public infrastructure and services, and longer trip distances. These ultimately lead to economic outcomes such as reduced employment in regional business activity, higher food prices and greater dependence on imported food, less clean air, fewer economic opportunities for those who do not have their own transportation means, more traffic congestion per capita, more accidents and pollution, and higher consumer expenditures on fuel (Todd 2015).
As discussed in Chap. 4, it is noted that in Africa the lack of urban planning, high land costs in urban areas, and household preferences for stand-alone housing have led to outward urban sprawl in most cities. In addition to the economic costs discussed above, a direct consequence of this type of growth is the delayed and costly development of urban infrastructure, and hence an increase in housing prices and in slum development. This calls for more dense cities vertically concentrated around main urban infrastructure and business district.
Building compact cities not only reduces the cost of housing construction and ownership, but also leads to sustainable use of resources. Research has shown that compact cities are environmentally more sustainable because of reduced energy use, greater viability of public infrastructure, preservation of agricultural land, and promotion of cultural diversity (CEC 1990, Kenworthy and Labe 1996). A study by PBL Netherlands Environmental Assessment Agency found that densification increases economic productivity and the creation of regional jobs reduces car usage (Nabilek 2011).
Beyond these benefits, densification of African cities will reduce self-built infrastructure, and hence construction costs, and encourage formal development of infrastructure. Indeed, the construction of high-rise apartments by housing developers often requires a formal process with adherence to urban plans and building codes. It is, however, noted that in some cities such as Kenya, private individuals in the informal sector are developing five- to seven-story rental apartments. These tenements are creating modern slums, where modern buildings with poor quality of construction lack basic infrastructure and promote overcrowding (Huchzermeyer 2007).
5.5.6 Alternative Building Technologies
Most of the building systems in Africa follow building methods used in developed countries, which are largely based on cement and steel construction. UN-Habitat (2013) notes that many of the building codes inherited from the colonial era favor the use of conventional building materials and technologies, consisting mainly of bricks and mortar. However, there are other types of materials, locally available and more environmentally friendly, that can be used for the construction of superstructures. Some of these technologies such as expanded polystyrene panels or cement reinforced mud blocks can speed up the construction process, reduce costs, and mobilize a larger number of workers.
Several factors explain the limited use of alternative building materials. The first is related to cultural biases that make customers reluctant to change. Acquiring or owning a house built with conventional materials is perceived as a symbol of status and wealth, as opposed to acquiring or owning a house built with local materials. For example, despite the superior energy efficiency and lower costs of earth blocks, customers still prefer cement blocks. This misleading perception is shared by architects and engineers, who prefer to use materials they are familiar with. Concerted efforts by governments and the private sector are needed to overcome this barrier and sensitize all stakeholders, starting with the architects, designers, engineers, and customers. In addition to this cognitive behavioral aspect, it is noted that government’s regulation can act as a barrier to adopting alternative building technologies. In such cases, appropriate policy reforms should be considered if authorities are concerned with promoting alternative building techniques. Building codes should be adapted to local realities (urban vs. rural), promote housing affordability, and favor local production of building materials. A third barrier is technological, as some materials are not adapted to some types of construction. For instance, areas with sandy soils are not appropriate when using earth-stabilized blocks. There is also an issue of quality, given the lack of standards. The final barrier is related to costs, which are high, given the low production capacity of those alternative technologies across the continent. During our fact-finding mission to Cameroon, it was noted that although earth-stabilized blocks are cheaper for a few housing units, the limited production capacity makes them uncompetitive for large-scale housing development. And the lack of access to finance is a key constraint for SMEs involved in production of such technologies.
Recognizing the issues of production capacity and standards, some governments have created agencies to oversee local building technologies. In Cameroon, the Local Material Promotion Authority (commonly known by its French acronym, Mission pour la Promotion des Matériaux Locaux—MIPROMALO) is the government entity tasked with promoting the use of local materials in construction. Its activities are focused on conducting applied research and product development, as well as providing technical assistance to SMEs in the production of local materials. MIPROMALO has identified compressed earth blocks as a viable alternative to cement blocks in many regions of Cameroon. As a result, it built a production plant with the capacity to produce 20,000 compressed earth blocks per day, although its utilization rate is 50 percent because it lacks dryers. Financial and administrative bottlenecks have also inhibited the effectiveness of the institution. Nigeria has an institution with similar objectives called the Raw Materials Research and Development Council. However, this institution has not been effective in fulfilling its mandate as local materials are not widely used.
5.5.6.1 Compressed Stabilized Earth Blocks
One of the most available building materials, used for centuries throughout the world, is soil. Earth construction has been the most effective means for building homes for people in developing countries and has shown promising results for an economical solution of the affordable housing problem, reducing costs by at least 25 percent in African countries. In addition, the thermic properties of soil blocks lead to lower internal room temperatures, making air conditioning unnecessary even in hot areas. In some countries such as Sudan, soil is the primary material used for the construction of traditional low-cost dwellings and is well suited to local weather conditions and occupancy patterns. Soil construction is used in 80 percent of urban buildings and over 90 percent in rural areas in Sudan. In other countries, however, there is a cultural stigma surrounding the use of earth blocks as they are associated with poverty. Moreover, poorly constructed and maintained soil buildings can easily discourage the adoption of this technology. Modern knowledge of soil construction techniques such as compressed stabilized earth blocks (CSEB) have been developed but not widely disseminated.
Many housing programs, led by either NGOs or the private sector, have aimed at promoting the use of CSEB. In Angola, Development Workshop (DW) trained clients of Kixi Credito, a housing microfinance institution, on the techniques of CSEB production used in its housing projects.Footnote 6 The results have been a gradual acceptance of the use of CSEB. CSEB is also available in Kenya and promoted by the Kenyan government. The Ministry of Housing established the Appropriate Building Materials and Technology Programme in 2006 to address the high building costs by facilitating the provision of improved and affordable housing in both urban and rural areas. The program purchased CSEB machines from the South African manufacturer, Hydraform, and trained individuals and community-based organizations to make interlocking CSEB. However, poor training and supervision from the government led to the failure of the program as the quality of houses built with the CSEB was poor.
Hydraform produces interlocking blocks using a mixture of soil (90 percent) and cement (10 percent), making the building process faster as well as simpler and more efficient. Moreover, the machines used do not require any specialized skills. These bulletproof and earthquake-resilient blocks have a low carbon footprint and can also be produced on-site. Hydraform’s biggest clients are the governments of Nigeria, Rwanda, and Uganda and their technology is present almost everywhere on the continent. The company also sells its blocks and machinery to private individuals, NGOs, and other private sector bodies. In Tanzania, the technology is reported to lead to a 30 percent cost saving over conventional brick-and-mortar technologies. Hydraform noted the reluctance of some builders to adopt the technology because of their familiarity and dependence on regular bricks-and-mortar systems. Lack of access to funding for budding entrepreneurs and limited capacity among small real estate developers were mentioned as additional challenges in scaling up this technology.
Lafarge has developed a technology of stabilized soil blocks consisting of 5–8 percent cement. This technology is currently being used in Malawi. Lafarge’s block manufacturing plant, DuraBric, assists in the design of homes and offers technical assistance. It reports savings of 40 percent over conventional technologies with the use of stabilized soil blocks.
5.5.6.2 Expanded Polystyrene Panels
Expanded polystyrene (EPS) is a lightweight plastic material used in various sectors including construction, packaging, and insulation. EPS panels are constructed by inserting EPS between two metal sheets. The panels are then assembled to form walls or roofs. The technology can reduce construction time and is energy efficient. It is the most common prefabricated building system proposed in Africa. Although ownership costs are estimated to be lower with EPS than with conventional technologies, construction costs depend on how the design is optimized and how much the panels cost. The Expanded Polystyrene Association of South Africa reports construction cost savings of about 30 percent. An additional advantage cited by the industry is the need for only a small crew for installation.
EPS panels are not widely used in Africa, given the limited local production capacity, low performance in noise reduction, and low consumer acceptance of alternative building materials in general. Notwithstanding these drawbacks, the government of Kenya is promoting the use of EPS panels in construction. In 2012, the National Housing Corporation built a factory to manufacture EPS panels based on the expectation that the EPS technology would reduce the costs of construction by up to 30 percent. However, the Kenya Federation of Master Builders estimates that the prices of imported panels amount to about half of the prices of the panels produced by National Housing Corporation’s EPS plant. Given their anticipated cost saving, EPS panels may be perceived as a solution to building affordable houses in Africa. However, there are a number of reasons to think the contrary. As discussed previously, technology choices should be consistent with the development imperatives of countries, which include job creation among others, and EPS technology is rather capital intensive. For instance, the factory in Kenya employs only 20 people and EPS panel installation is not labor intensive. Moreover, the cost savings do not materialize at project completion, but only after including ownership costs. Another disadvantage is that the production technology uses oil, a nonrenewable fossil fuel, as raw material, which is costly in some countries.
5.5.6.3 Other Alternative Building Technologies
Various other building technologies have been studied and found to be cost-effective and energy efficient. These include cross-laminated timber, bamboo panels, and materials such as composite panels made of elephant grass, coconut husk, and the like. Although these materials are widely available in Africa, the long-term sustainability of its production is not certain. For instance, the continent is experiencing a rapid rate of deforestation so it may not be possible to make sufficient timber panels to meet the affordable housing gap. In addition, manufacturing units are required in order to transform the raw materials into construction panels. Thus, many technologies are still in their laboratory phases and are unlikely to be the solution in the near future.
5.5.7 Capacity Building and Skills Training
The discussion earlier highlighted the importance of having the right skills mix throughout the housing supply chain as it entails faster construction with less rework and, hence, results in lower construction costs. Therefore, as African countries seek to scale up housing delivery, capacity building should be an integral part of their programs, as in Ethiopia (see Box 5.1). Education programs need to be overhauled in order to give greater importance to TVET. In this process, multilateral organizations such as the AfDB and UNESCO can play an important role. The AfDB should place greater importance on the availability of practical skills in key economic sectors, including construction. This will help solve the problem of high unemployment rates as well as the issue of skills shortage. During our fact-finding missions in different African countries, a number of stakeholders cited skills development and trainings as areas that need support from development partners.
Besides, another potential area that needs support is capacity building for SMEs involved in housing construction. As noted above, SMEs in the sector have limited access to capital, but they also have poor project management skills. Technical assistance programs combined with increased financial access, through either equity or debt, can help improve their capacity to deliver affordable housing. One of the major findings from this book is that by contrast to the general belief, financial assistance alone may not solve the problems of SMEs in the construction sector. Shelter Afrique’s experience working with developers has revealed that defaults from SME housing developers in various countries are often driven by poor capacity in project management and marketing. In the same vein, while the economic literature has shown that in developed countries, provision of financial assistance to SMEs improves their probability of survival and growth, evidence has shown that this may not be the case for developing and transition countries (for a review of the literature, see Bah et al. 2011). Housing developers interviewed in various countries across the continent recognized the lack of managerial skills as a key constraint, pointing to the importance of capacity building and skills development.