Unfired clay materials and construction

Strictly speaking, the use of clay soil is not nonconventional. It is only nonconventional compared or in competition with the use and application of the more energy-intensive and less environmentally friendly materials such as concrete and steel. The use of clay-based materials has a long and prehistoric background. Their association with mud huts is correct but not sufficient, and there has been serious rethinking and modernizing, such that clay-based materials can now produce aesthetically pleasant construction. Good workmanship can be achieved for both individual and large-scale housing projects using unfired clay materials, in both developed and developing countries. This chapter focuses on the use of these materials, starting from the basics – the structure of clay soils. An appreciation of clay structure and mineralogy is critical to the unlocking of some of the key steps necessary for soils’ optimal performance, more especially on stabilization with either the traditional binders of lime and/or Portland cement and/or any of the emergent sustainable binders that have increasingly become available in the building and construction sectors in the past decade. With this soil science background, the chapter is aimed to capture interest among academicians, researchers, and trainers in the subject. By progressing to application, durability, and future trends with clay-based technology, the chapter also has interest with building and construction practitioners, materials manufacturers, and policy makers in both central and local government authorities. All these parties have a common interest in low-cost housing, care for the environment, and the sustainable development of community infrastructure, such as that unparalleled by the uptake of soil-based appropriate technology.