The performance of an experimental roof of papyrus sandwiched with polythene sheet.

Abstract

As part of the efforts to arrive at alternative solutions for roofing at lower cost, an experiment of a modified papyrus roof was carried out. Polythene sheets of three different thicknesses were placed between two layers of papyrus mats. This experiment was initiated by Mr. J. Eygelaar, materials engineer of the HRDU, in 1977. Though in certain rural areas "in Kenya, papyrus is used as a roofing material, transportation of big quantities is very costly, which in turn reduces the amount available for roofing. Polythene for water tightness was thought to be a good replacement, due t6 the limited availability of papyrus. An experimental roof was erected on a terrace of the building of the Faculty of Architecture, Design and Development of the University of Nairobi. (See Photograph 1 below) . Photograph 1. Overall view of the experimental roof structure. The purpose of this experiment was (i) to check the durability of papyrus against rot, fungi and tear, (ii) to check the durability of black polythene sheeting against ultra violet radiation, heat, rot and (iii) to check the combination of both materials. This study only deals with the technical aspects of these materials. Acceptability of this type of roof in rural areas where papyrus is largely used, has riot been investigated. Papyrus is also used for sleeping mats in the rural areas. -4- photograph 2. Detailed picture of the method of sandwiching the polythene and papyrus mats. View of