STRUCTURAL GLASS FACADES - USC School of Architecture

2.5.6 Point-fixed Glass Systems
Point-fixed glazing systems find most frequent use in structural glass façades. The glass
panes are either bolted or clamped with components providing attachment to the truss
system. The most common system type is often referred to as a “spider” system. A fourarmed
fitting, usually of cast stainless steel, supports four glass panes at adjacent corners
on the glazing grid and ties back to the truss system. The spider fitting is designed to provide
for glazing system movement under environmental loading, as well as to accommodate
specified field tolerance during assembly. A variety of spider systems are available from the
suppliers of cable and rod rigging systems.
Cast stainless components can be quite expensive, especially if large, customs spiders are
required, as they often are in large glass grids. Alternate strategies can be lower tech, lower
cost, and just as effective depending upon the aesthetic goals of the project. Simple
stainless spring plates have been used in place of a cast fitting with excellent results.
2.5.7 Point-fixed Drilled
The dominant strategy for the point-fixing of glass
since the advent of the suspended glass wall has
been mechanical attachment with a fitting that
accommodates a bolt through a hole drilled in the
glass panel that ties it to supporting structure.
There are variations of these fixings on the
market, and the refinement of detailing and
performance varies considerably. All use
stainless material. Some are large discs that
stand out from the glass surface. Pilkington’s
Figure 2.37 Point-fixed insulated glass with
butt-glazing (ASIDI).
version features a custom bolt head that sits flush
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