A Study of Roof Failures in and around Ibadan, Nigeria: Causes, Effects and Remedy

摘要

A random survey was carried out on the preponderances of roof failures and possible causes in Ibadan, a city in Oyo State of South-Western Nigeria. The survey was carried out using structured questionnaire, interview schedule; focus group discussion (FGD) and personal observations with photographs recording. Information of interest and which were included in the instruments were the types of roof, materials used in the construction of roof trusses and sheathing, age of roof, maintenance practices, causes of failure and their subsequent consequences.The survey revealed that all categories of roof of different ages are affected in all locations of the city both at the urban and rural areas. The identified causes of roof failures include Poor workmanship, design error; age and environmental forces, materials inadequacy, roof geometry and topographical with relative frequency of occurrence of 30.48%, 14.76%, 10.28%, 18.64%, 14.08%, and 11.76% respectively. The study revealed further that roof failure has economic, social and emotional effects on the affected people. Routine maintenance programme, proper construction, provision of courtyard, adequate drainage, good slope and roof overhang will minimize incidences of roof failures and are these therefore recommended.