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Beskrivelse
It is recognized that the most serious deficiency in the provision of low cost housing in developing countries is the lack of suitable low cost roofing. The roof is an essential component of a dwelling and is critical to shelter, thermal comfort and privacy. It will be recognized that in establishing the suitability of a material for roofing, it is necessary to determine criteria for the whole roof: it is necessary to consider such factors as the architectural design, the construction detailing and sociological factors.The use of organic fibers in a roofing material compares reasonably with the requirements. Organic fibers are hygroscopic and are not dimensionally stable under conditions of varying moisture content. Not only will loss of bond between the fiber and matrix results but also the strength will decrease. In time, under conditions of high moisture content, the fibers will rot and disintegrate. Hence it is necessary to ensure that the fiber moisture content is very low and stable if reasonable composite life is expected. During the last decades, knowledge of natural fiber use in cement composites, mechanisms of mechanical behavior, insulating behavior, etc. has increased substantially.