STRUCTURAL GLASS FACADES - USC School of Architecture

Especially when dealing with innovative building technology, the designer needs input during
design development as to the impact design decisions are having on the material,
fabrication, assembly and erection aspects of the design. Designing in the absence of this
information is inviting problems during the construction phase of the project. The same
applies to cost estimating. If the designer is not informed as to the cost of the various design
decisions, the ability to predictably meet target budgets will be significantly compromised. A
preliminary level of structural analysis must be undertaken to address these issues. The
input that is required is considerable and specialty façade contractors may be reluctant to
provide such services up front and without compensation with no assurance of being
awarded the project. Design/build and design/assist methods are discussed below as
possible strategies to resolve this dilemma and provide adequate technical input early in
schematic design when it is most needed.
The need for input early during schematic design can be exacerbated by the materials and
processes that are involved in structural glass facades. The architect may be inexperienced
with point-fixed glass systems, exposed steel structures, machines and cast stainless steel
components, rod and cable rigging systems; all are relatively unfamiliar to most practitioners
in the building arts. It is imperative that these elements be properly designed for and
specified in the bid documents.
Erection costs can be especially difficult to determine during the early design phase. The
project delivery methods described below provide the great potential value of having the
installer involved during design development, informing the design, and contributing
preliminary costing information regarding the installation work. Much of installation cost is a
function of site labor, a particular consideration in highly priced labor markets such as the
US, where installation costs can approach half of the total project cost. In contrast, site labor
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