Volume 5, Issue 10 (November 2008)
Envelope Remediation—A Case Study in Support of an Over-Cladding Approach
This paper addresses a case study in which a contemporary, high-performance glass curtain wall and a composite metal panel cladding system were installed over an existing failed 1960s masonry wall with aluminum windows. In addition to consideration of the typical performance requirements for air and water infiltration and thermal insulation, the new wall systems were designed to meet glass shard retention requirements and to accommodate improvements to the structural frame required by the General Services Administration. These performance requirements were all met while creating a more inviting exterior appearance, improving the interior work environment, extending the building’s service life, and reducing energy consumption. Problems of the original design and construction, extent of previous remediation attempts, findings of the investigation of the existing building, and the development of remediation options are discussed to provide background to selection of the over-cladding approach for remediation. Opportunities and limitations posed by the existing building, LEED requirements, glass shard retention, construction strengthening, full and uninterrupted occupancy, as well as other challenges inherent in the over-cladding of an existing high-rise building on a tight urban site are identified and discussed, and positive results are identified.