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By: Robert Grupe
Director, Architectural and Technical Solutions, United States Gypsum Company

Phil Shaeffer
Manager, Codes and Technical Support, United States Gypsum Company

Dean Updegrove
Product Marketing Manager, United States Gypsum Company

Continuing Education Use the following learning objectives to focus your study while reading this month’s ARCHITECTURAL RECORD / AIA Continuing Education article. Learning Objective: After reading this article, you will be able to: 1. Understand the essential performance and design criteria used to select and specify cavity shaft walls; 2. Know how gypsum drywall shaft walls perform and install; 3. Create gypsum drywall shaft wall design specifications optimized for abuse resistance and moisture control.

With the advent of high-rise construction, vertical shaft wall systems have become a critical element underlying successful building design. These walls, which house elevators, stairwells and mechanical utilities, enable safe occupant egress and ensure the reliable flow of air, water, heating, cooling and other essential utilities throughout a building.

From a life safety standpoint, shaft walls are the most important walls in any building. In the event of a fire, shaft walls ensure that occupants have a means to exit the building (via stairwells) and that firefighters can access the building (via elevators and stairwells). In addition, the type of shaft wall constructed and its location impacts the amount of usable space in a building. Lastly, by including abuse-resistant design into shaft wall specifications, these walls can positively affect building life cycle costs.

To properly specify shaft walls for low-, mid- and high-rise construction, architects must know the types of systems available, as well as the performance and installation attributes of each. Based on this knowledge, architects can then select – and specify – the system that best meets specific project life safety and structural performance requirements.

A Brief History

Prior to the advent of high-rise construction, the traditional materials of choice for shaft walls included masonry, structural clay tile and gypsum tile. In 1931, for example, the architectural firm of Shreve, Lamb and Harmon specified masonry shaft walls for the Empire State Building, which is considered by many to be the first modern high rise. In that same year, Graham, Anderson, Probst and White selected gypsum tiles for the construction of the 4-million-square-foot Merchandise Mart in Chicago.

However, as buildings reached farther into the skies, the search for lighter, more elastic shaft wall systems became a priority. Traditional hard and brittle materials, such as structural clay and gypsum tiles, limited the design capabilities of shafts in modern high-rises and placed constraints on the finished spaces within those buildings. In response to these needs, gypsum panel shaft wall systems were introduced in the 1960s. The first project to use these gypsum panel systems was a small office building in Los Angeles. This application was followed by a gypsum panel installation on the Central National Bank Building (designed by Charles Luckman and Associates) in Cleveland, and then at the U.S. Steel Building (designed by Harrison Abramovitz and Abbe) in Pittsburgh.

Based upon these early efforts, designers today have much more flexibility in both cavity shaft wall material selection and system design. Material choices now include poured- in-place concrete, masonry, gypsum plaster, metal stud drywall or specially designed gypsum drywall shaft wall systems. Given certain design parameters for the shafts and the end use of the structure, any of these may be appropriate for a given building. (See Shaft Wall Performance Comparisons table included in the additional online reading materials.) But determining which system is best for a specific structure requires careful research.

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