EIFS Sealant Joint Restoration

Abstract

The successful performance of exterior insulation and finish systems (EIFS) is related directly to the sealants used to weatherseal the EIFS and adjacent materials to EIFS. With millions of square feet of EIFS installed, proper restoration of EIFS joints can help ensure long-term watertight performance of the EIFS wall. A new test method that closely parallels ASTM C 1135—Test Method for Determining Tensile Adhesion Properties of Structural Sealants, is currently under consideration by ASTM Task Group C 24.20.12. This new test method allows sealant joints to be evaluated in many conditions to more closely simulate actual field conditions. This paper will focus on types of EIFS joint failure and possible causes for failure. Different restoration methods will be discussed with particular attention to the use of sealants to overlay failed sealant joints. A modification to the test method under review by ASTM Task Group C 24.20.12 will be used to evaluate various joint conditions with EIFS, including standard square joints, hourglassshaped joints, overlay joints with wet sealants, and overlay joints with performed sealants.