to the top. They are supported by steel cables embedded in the concrete in a curve similar to that of cables supporting a suspension bridge. Their rectangular openings, which are high in the center and at the ends, allow maintenance workers to move easily through the thicket of pipes and ducts on the service floors. The trusses impose strictly vertical loads on their support columns, to which they are attached not rigidly but with a system of slip plates and tension cables to permit small movements during moderate earthquakes. After two years of design work, and even after the design had been approved and meetings with potential building contractors had begun, Kahn and the Salk Institute abruptly decided to reduce the number of laboratory buildings from four narrow ones to two wider ones and to increase the number of floors per building from two to three. Komendant re-engineered the structure and produced a new set of drawings with a speed that professor Leslie described as "legendary". He also trained the construction workers in techniques for producing a highly refined concrete finish. In 1992 the American Institute of Architects (AIA) gave this building its prestigious Twenty-five Year Award, which is given to only one building per year. First Unitarian Church of Rochester At the First Unitarian Church (1959–1969) in Rochester, NY, Kahn faced the challenge of placing a heavy concrete roof structure between four light towers in the corners of the sanctuary without using support columns in the interior of the room. Not entirely satisfied with the roof design he had developed, Kahn asked Komendant for suggestions. Komendant kept Kahn's general layout of the roof but redesigned it as a folded-plate structure of pre-stressed concrete that would require support only at its edges, eliminating the need for the massive concrete beams that Kahn had been planning to use as its support. Kahn adopted Komendant's design, although with modifications. The contractor in charge of construction had no experience with this type of roof structure, so Komendant agreed to inspect the forms before concrete was poured and return after the concrete had cured to supervise the hydraulic tensioning of internal support cables. The contractor feared that the heavy roof structure would collapse when the forms were removed, but Komendant assured him that it would settle no more than . It actually settled less than . Paul Goldberger, architectural critic for The New York