Indigenous earth building construction technology in Ota, Nigeria
This paper documents the earth construction techniques used in Ota in order to preserve the earth construction heritage of the Ota people while checking the suitability of the earth materials used, using soil classification tests. Interviews of earth constructors in six villages in Ota were conducted to determine their material selection criteria, material processing and construction techniques. Colour and texture of soil samples were determined and in-situ tests such as biscuit, cigar, hand-wash and adhesion tests were performed on soil samples used for earth building construction at three of the villages. Natural moisture content, sieve and hydrometer analyses, and Atterberg limits test were performed in the laboratory, on soil samples taken from these three locations. It was revealed from the interview sessions that cob construction technique is widely used and that earth building construction is becoming less-appealing to the youths in these locations. The soil samples at the three locations were classified as clayey sand and were ascertained to be suitable for earth building construction. Earth constructors in Ota perceive that earth buildings are more economical and energy-conserving. Earth buildings are a potential solution to the global housing crisis experienced, especially in developing countries.