With its turrets, crenellated parapets and other architectural flourishes, rich textures, and loadbearing masonry walls, Mary Gates Hall evokes a bygone era of ornate design and exquisite craftsmanship, yet the building incorporates very modern engineering methods.
Bassetti Architects in association with Hartman-Cox Architects "set out to design a building that looks 100 years old, and they did it," observed coordinating judge Colin Munro. A beautiful and traditional use of masonry, the building "confirms that you can take a wonderful material and do anything you want with it."
The project consists of a 59,000-square-foot addition to the university's 1928 Collegiate Gothic-style Physics Hall, an extremely ornate four-story building with brick veneer over a concrete structure. A slightly less ornate addition in 1948 formed an L-shaped complex when combined with the original structure. The designers decided to give the new addition an L shape as well so that the completed complex would be a more seismically stable rectangle, wrapped around a central commons. "The project is in an area that is seismically active and is very innovative in terms of engineering," Dan Shapiro noted in the final phase of the judging.
KPFF Consulting Engineers, which submitted the winning entry, chose the unusual approach of tying the new and old structures for lateral resistance instead of separating them with seismic joints. "The new exterior masonry wall is incorporated in the lateral force system as a punched shear wall and masonry moment frame, adding to the seismic resistance of the building," explained project manager Greg Schindler of KPFF. A double-wythe composite wall, the exterior wall is composed of reinforced concrete masonry and an exterior structural wythe of brick with a solid grouted collar joint. KPFF's principal-in-charge John Tawresey uses the term "mass wall" for this 14-inch-thick wall because the entire masonry thickness is used for structural strength. Both the CMU wythe and the collar joint are heavily reinforced, with #4 rebar used horizontally and #6 rebar used vertically at window openings. The brick wythe is anchored to the CMU wythe with stainless-steel pintel-and-eye-type ties.
The new addition required an exact replication of the masonry and cast-stone ornamentation of the original building. The brick coloration, texture, blend, and patterning had to match that of the old building as closely as possible. The transition between the old and the new "is meant to be seamless," said Marilyn Brockman, principal of Bassetti Architects and a trained historic preservationist. Where the new brick meets the original, "the new building is always in shadow so it wouldn't be obvious." Molds from the original cast-stone were created for the cast-stone elements on the addition. These cast-stone pieces contain weld plates and holes, allowing their full integration into the facility's structural performance. The project was "rigorously executed," emphasized competition judge Pat Rand.
"This was a once-in-a-lifetime opportunity," stressed project superintendent Larry Shultz of Henson's Masonry. The four masons who did the most work on the job each won the privilege of resetting one of the four original 100-pound gargoyles that had been removed during the restoration.
The job was gratifying but not easy. "One of the challenges was how far we could go with the grout without pushing the brick off the walls," Shultz noted. The firm opted to grout the 2 7/8-inch collar joint in 2-foot lifts to prevent the brick wall from blowing out. Because the collar joint was reinforced vertically with an extensive amount of #6 rebar, Henson's Masonry used a plasterer's pump to pump very fine grout (a slurry) into the space so that the rebar would be sufficiently surrounded by the grout. What's more, every piece of stone had to be anchored to the CMU backup. This painstaking work is today a great source of pride for Henson's. Shultz is quick to praise the contributions of everyone on the project team, including the masons and laborers. The masonry work took 14 months to complete.
Owner:University of Washington, Seattle
Architect: Bassetti Architects, Seattle, in association with Hartman-Cox Architects, Washington, D.C.
Structural engineer: KPFF Consulting Engineers, Seattle
Masonry contractor: Henson's Masonry, Seattle
General contractor: Hensel Phelps, San Jose, Calif.
Masonry supplier: Mutual Materials, Bellevue, Wash.
Cast stone: MJM Studios Architectural Sculpture Service, South Kearney, N.J.
Landscape architect: Nakano-Dennis Landscape Architects, Seattle