STRUCTURAL GLASS FACADES - USC School of Architecture

Resources and Technology
Materials and Processes: Glass fabrication requires special processes, drilling at minimum.
Hardware systems range from machined and/or cast stainless steel components to simple
metal plate systems.
Material Suppliers and Subcontractors: At least two suppliers provide complete engineered
and waranteed systems including glass and all hardware. These are good options, but
expensive. A viable alternative is to specify an off-the-shelf hardware system and a glass
supplier offering a point-fixed glass product. Over the past decade many fabricators of
hardware systems for point-fixed glass systems have emerged with catalogs full of product.
Glass supply for drilled point-fixed applications has been more problematic. For many years
the large majority of point-fixed glass came from just a few European sources. However,
more glass fabricators have entered this market in recent years providing more local and
economical sources of glass supply.
Durability and Maintenance: These are very durable, low maintenance systems beyond the
cleaning of the glass. The extensive use of stainless steel and the fact that the structural
components are normally inside the glass envelope are a major factor. The butt-glazed
silicone seal has proven to be an excellent performer.
Structural Performance
Spanning capacity: This is accommodated solely by the glass panel and is a function of the
bolted connection at the glass and the makeup of the glass panel. The deflection of insulated
glass units stresses the spacer seal, and manufacturers typically place limits on the amount
of deflection for which they will provide a waranteed system. This ranges from L/100 to
L/140. The other factor is the glass bolt, of which there are two basic types; one clamps the
glass at the hole location preventing rotation and limiting deflections to some extent, but
transferring bending forces into the glass as a result; the other type of bolt incorporates a
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