ROOFING SYSTEMS unicular Shell F Most materials behave best in compression but we force materials against their inherent values thus causing more problems than resolving them. The roofing system consists of waste stone masonry funicular shells. A funicular shell is the equivalent of a 3 dimensional catenary, developed on a rectilinear base. Funicular shells have been loaded to ten times the design loads of RCC and have come out winners all the way. Even the weakest of materials when used in compression will surpass RCC used in the flat form. A flat arch rotated around the centre results in a load bearing brick roof without the use of steel. The funicular shell roof is one such compression structure, which ensures conservation of natural resources by utilising waste materials effectively and optimising the use of expensive steel and cement. Further, the arch distributes the point load in all direction equally thus, is able to withstand impact loading at any point. Diagonal g rid of funicular shell gives the illusion of a larger space. ! Eliminate use of high-energy steel reinforcement used in the conventional RCC roof. ! Allows efficient use of waste materials and provides personality, colour and texture. ! Minimises requirement of internal plasters. ! Provides roofing at a lower cost. In these illustrations a square base of size 2.2 m X 2.2 m has been used. However, any size and proportion is possible. Design of Funicular Shell Roof The entire area to be roofed is divided into a grid depending on the size of the funicular shell required or the size / shape of moulds available. The Edge beam / supporting beam is half cast. The reinforcement cage of the edge beam can either be pre welded or made in the conventional manner. The rise to span ratio is 1:6 thus; the optimal span of the shell is 3m though it can span up to 15m. The mould is supported between the edge beams. Timber planks are used to bridge the gap between the edge of the mould and the edge beam. A thin layer of sand is put on top of the mould with a layer of the finishing materials- brick / stone tiles / mud blocks etc. along the curvature of the mould or according to individual choice. Interesting patterns may be created by artistically mingling the chosen materials along with waste by- products e.g.- edging of marble / granite slab or broken tiles etc. Cement slurry in the ratio 1:2 is poured over the assembly and is allowed to settle. It keeps the finishing appropriate technologies