Building materials constitute the single largest input in the construction of housing, often accounting for as much as 80 percent of the total value of a simple house. However, those available on the market in most developing countries are either prohibitively expensive and in scarce supply, or of low quality. In a large number of countries, the import content of construction activity is up to 30 percent of the value of gross output, which may comprise up to 60 percent of all materials. In addition to finished products, developing countries are importing factor inputs such as machinery, energy and raw materials. The increasing dependence on imports has imposed a severe strain on the balance of payments and fuelled inflation.
In an attempt to overcome the problems of the shortage and high cost of building materials, many governments have opted to establish large-scale factories to produce basic building materials. Natural resources are usually in abundance. However, many of these factories have been faced with numerous difficulties arising primarily from the choice of imported technologies, or demand fluctuations and lack of capital for the build-up of supplies.
The small-scale sector of the building materials industry, however, has shown considerable potential in meeting the local demand, despite the fact that it often relies on traditional and outdated technologies. Lack of knowledge of innovative, energy-efficient and appropriate technologies bases on local resources has been the biggest stumbling block in improving the productivity of this sector.
The UN Centre for Human Settlements recommends the following actions for improving the building materials sector to support the provision of low-income housing: (1) using appropriate, innovative and energy-efficient production technologies; (2) strengthening capacities of the small-scale sector to meet local demand; (3) supporting small-scale building materials industries through legal and fiscal incentives, access to credit, research and information; (4) providing policies to facilitate fair market competition; (5) reformulating and adopting building standards and by-laws to promote the use of low-cost building materials; (6) strengthening research efforts and translating successful research findings into commercial production; (7) promoting the flow of information on suitable technologies and arranging on-the-job training programmes for artisans and technicians; (8) formulating and adopting standards and specifications for low-cost building materials production and use; (9) promoting information exchange of appropriate building technologies; (10) promoting transfer and adaptation of technology through international and regional cooperation; (11) promoting partnerships with the private sector and NGOs for the commercial production and distribution of building materials; and (12) encouraging active participation of the informal sector, communities and women.