Mandala roof
The mandala roof is a conical roof structure for buildings with a polygonal floor plan.
A mandala roof is primarily based on a polygonal (usually octagonal ) or round floor plan of the building. From each corner of the building, a rafter leads upwards at an angle, slightly past the center of the roof. Each rafter lies on top of the next. In this way, the rafters are wedged in a ring around the center of the roof. The angle of inclination of the roof is determined by the thickness of the rafters compared to their length. Only low external shear forces arise on the roof supports . The rafters are connected and fixed at the foot of the roof by purlins . An unusual feature of this construction is that all the rafters are needed to give the roof stability. If only one breaks, the roof will collapse.
A mandala roof is a cantilever structure without internal pillars. In the middle of the roof there may be an opening within the ring of the wedged rafters. In Central Europe, mandala roofs are mostly used for exhibition pavilions, exhibition stands, garden houses or the like.
The name is derived from mandala , a circular Indian religious symbol.