Solid but how?

Frank O. Gehry is doing it, Oswald Mathias Ungers is doing it, Peter Zumthor is doing it, Christof Mäckler is doing it and (http://maplered.com) Hans Kollhoff is doing it; they are all building with solid Stone (http://g603.net) . Whereas a few years ago the natural Stone (http://g603.net) façade had become an external sleeve - a clever theme or ironical interpretation for cosmetic purposes, many of today’s architects are falling back on the construction method of a facing shell of natural Stone (http://g603.net) . This is covered in Germany by DIN 1053. Non-bearing exterior walls must be at least 90 millimeters thick and (http://maplered.com) fully supported over the whole area. Outer shells less than 115 millimeters thick must not be built more than 20 meters above ground and (http://maplered.com) must be supported at height intervals of about six meters. The masonry shells are to be fixed by wire anchors or approved retaining anchors of stainless steel. In double-shell exterior walls with air layer and (http://maplered.com) heat insulation, the clear space between the masonry shells must not exceed 150 millimeters. The minimum thickness of the air layer is 40 millimeters.