Wall Cladding System Durability Lessons Learned from the Premature Deterioration of Wood-Framed Construction Clad with Exterior Insulation and Finish System (EIFS) in the U.S.

April 29, 2005
Publication: 10DBMC International Conference On Durability of Building Materials and Components LYON [France] 17–20 April 2005
Author(s): Matthew Bronski

Abstract: Despite well-intended laboratory testing of individual materials and components, unanticipated and severe durability failures of building wall systems can occur when the system design does not adequately integrate the various materials and components within the wall. Wall systems often fail when the design does not anticipate the deterioration and failure of individual components (such as sealant) and minimize the adverse consequences of such localized failures. Exterior Insulation and Finish System (EIFS), a.k.a. 'synthetic stucco', is an exterior-wall-cladding system that had been used on mass masonry wall construction in Europe since the 1940s and in the United States since approximately 1970. From the mid-1980s to the early 1990s, use of EIFS cladding became common on wood-framed residential construction in the U.S. Despite prior laboratory testing of the cladding system, unanticipated and spectacularly rapid deterioration problems occurred with the wood-framed walls beneath the cladding, particularly in regions with significant rainfall and humidity, such as the southeastern U.S. The EIFS cladding itself was typically intact and undamaged; however, the EIFS cladding trapped leakage from windows, sealant joints, and other wall components, resulting in the rapid deterioration of the underlying structural wood framing and/or the wood- or gypsum-based sheathing. Extensive durability testing of individual materials and components alone is not adequate to ensure the durability of a wall system. To be durable over the long term, wall system designs should consider in detail the integration of numerous wall components (e.g., windows, cladding, sealants, etc.), anticipate the degradation and failure of individual components (such as sealant), and design the system to accommodate such localized component failures and minimize their adverse consequences.