Photo by DeSimone Consulting Engineers

SAVE SPACE WITH STEEL PLATE SHEAR WALLS

When space is tight and concrete shear walls are demanding large amounts of floor area, steel plate shear walls can play a major role in the design of a building. Steel plate shear walls (SPSW) are thin plates located between columns that save valuable floor space in lieu of using thick concrete shear walls. These steel shear walls are commonly used in slender buildings that require great stiffness with limited floor area usage. Prefabricated steel panels are installed on site with minimal field work, increasing the speed of construction rapidly compared to cast-in-place concrete shear walls. Reducing the time for installation is a key time saving factor, which can significantly reduce associated labor costs. A study performed by structural engineers Sellie and Hooper concluded that an approximate 2 percent gross area savings was achieved by implementing steel plate shear walls instead of a typical concrete shear wall.³

Photo by DeSimone Consulting Engineers

IN-WALL BEAM: HIGHLINE 23

Highline 23, in New York, is a perfect example of a condominium building which had multiple space constraints. Designed by Neil M. Denari Architects with DeSimone Consulting Engineers, the 14-story luxury residential tower is built upon a narrow 40 by 49-foot site area. The floor area increases as the building grows taller. Large trusses are used to support the longer spans and also define the building aesthetic. The project utilized the in-wall beam framing method and steel plate shear walls to create more efficient space and to construct the building economically.

Conventional Solutions

Conventional methods of steel beam and column framing are commonly known for use in nonresidential building types such as offices and schools. Structural steel framing is once again proving to be beneficial in high-density residential projects as the speed of erection allows for building completion faster than all-concrete framing solutions. Similar to the in-wall beam framing system, conventional beam layout can span long distances. High floor-to-ceiling heights, common in luxury apartment and condominium design, do not have to sacrifice floor space by using heavy, massive concrete columns. Ceilings may be exposed to lofty structure or finished to house recessed lighting. New buildings take advantage of the speed and versatility of steel framed construction while maintaining the high quality and strength only found in structural steel.

Photo by Kessler Photography

CONVENTIONAL SOLUTIONS: THE CANOPY LOFTS

The Canopy Lofts rise seven stories in the historic haymarket district of Lincoln, Nebraska. Designed to entice the young professional market, 70 apartments provide 9-foot clear ceilings in the living spaces with 11-foot-4 inch floor-to-floor heights. The ground floor is made up of retail spaces with six floors of one-, two-, three-, and four-bedroom apartments above. Symbolically representative of the railway system which used to run across the site, architecturally exposed structural steel is a common theme throughout the development. The units contain a mixture of exposed beams, coated with a dark gray intumescent paint, and finished ceilings with recessed lighting. According to the co-developer and co-owner of the property, Chief Industries, Inc., fast erection with an all-weather system of construction was highly desirable to bring the building to market on time. “We wanted the best out there,” states Roger Bullington of Chief Industries, Inc. From an owner’s perspective, a long-lasting building of high quality makes the project a valuable investment and serves the community well. Due to the visible speed of construction of the Canopy Lofts, other local buildings in development have reconsidered using traditional concrete framing and revised their designs to incorporate structural steel.