The Alfred Newton Richards Medical Research Laboratory (Richards Building) at the University of Pennsylvania is one of the most important buildings in the career of architect Louis I. Kahn and one of the great buildings of the 20th century. Designed 1957-1958 and completed in 1961 the Richards Building was at the time deemed an architectural milestone worthy of a solo exhibition at the Museum of Modern Art in New York. In 2008 the Richards Building was nominated for and granted status as a National Historic Landmark (NHL). As a NHL the building must be treated with exceptional care, with particular regard for its outward appearance and the integrity of its material palette. As an occupied, working building any renovations must with equal vigor and discipline consider necessary changes to the interior and exterior to better serve the functional purpose and the needs of present-day occupancy and operations.
One of the signature elements of the Richards Building is the remarkably detailed and constructed exterior envelope consisting of co-planar exposed concrete structure, brick and monolithic, polished plate, fixed glazing set in custom fabricated bent stainless steel frames. Kahn’s use of heavy gauge, matte (‘pewter’ in his parlance) finish sheet stainless steel, both as panel and brake-formed as a framing material became a trademark – though little discussed – element of his design vocabulary until the end of his career. The use of this material begins with the AF of L Medical Services building in Philadelphia (demolished 1973) designed 1954-55, where we can witness Kahn’s testing early details utilizing more conventional rolled steel and extruded aluminum glazing sections before finally arriving at – and executing – a bent plate design. The system employed In Richards evolves out of these early explorations into one that uses the folded steel to create both shadows and strength, enabling a frame of unique lightness and remarkable elegance – that allows the glass itself to float almost weightlessly within the building frame.
A comprehensive renovation project was the catalyst for fully evaluating the exterior envelope and developing a design approach that retained the iconic visual and material characteristics of the building as viewed from both the exterior and interior while radically improving the energy performance and functional qualities of the building. This presentation will review the history and development of Kahn’s glazing system and unveil the comprehensive approach that was undertaken by an integrated design team including architects, engineers, materials conservators and building envelope specialists on how best to conserve the original steel framing and bronze entry doors while optimizing the overall performance of the exterior envelope and building systems. The process included developing a detailed understanding of the original design intent for not just the building envelope but the entire construction including the engineering systems and using that knowledge as a basis for developing design alternatives and a conservation plan that responded to the stated design objectives at different levels. In concert with the owner and the contractor a final design was developed that best balanced preservation, energy efficiency, economy and constructability.