STRUCTURAL GLASS FACADES - USC School of Architecture

Morphology
Another technique for the structure to diminish in appearance and thereby enhance
transparency in long-span facades is to substitute glass components for conventional
metallic components; a strongback or truss is replaced with a glass fin construct. With a
glass fin supported system, monolithic or laminated glass fins are positioned perpendicular
to the glass plane at the vertical glass seam to stiffen the wall against wind loads. Early
systems utilized a patch fitting to attach the glass, effectively restraining the glass at its
corners while providing for building and thermal movement. Contemporary systems
commonly use drilled glass panels and countersunk stainless steel fittings to fix the glass to
the fin. This structure type provides for an all-glass façade in spans under approximately 15
ft (4.6m), and a near all-glass façade in spans of up to 100 ft (30m), and of indefinite length.
Design Considerations
Aesthetics: These are minimalist systems with a unique transparent aesthetic.
Transparency (and control): The origins, while not the roots, of structural glass facades can
be traced to this structure type. Some would argue that this remains the most transparent of
the façade types. After all, there is virtually nothing but glass in the system, not even the
cables of the cable net structures; how could it not be the most transparent. However, the
lateral stability for this these systems is provided by glass fins that extend back
perpendicular to the glass surface, creating a layering of glass that is easily read from most
vantage points. This affect is not present with the membranes provided by the cable nets.
This is and will always remain one of the most transparent systems, but it is the opinion of
the author that the flat cable nets and cable hung structures provide optimum transparency.
Geometric flexibility: Heat-treated laminated glass is being used increasingly in structural
applications as beam and column elements. The latest high-profile example of this is the
glass cube by Apple in Manhattan; the entire structure and cladding are glass. There are
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