Page 387 - Construction Waterproofing Handbook
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REMEDIAL WATERPROOFING  8.47

























                         FIGURE 8.52 Application procedures for remedial joint treatments. (Courtesy of Dow Corning)


                            Barrier EIFS systems are more difficult for correcting leakage problems than the now
                         more frequently used EIFS divertor systems that include drainage systems behind the
                         synthetic finish. Repairing barrier systems can involve the complete removal and replace-
                         ment of the system due to the structural repairs necessitated, as shown in Fig. 8.54. The
                         new systems should be replaced in accordance with manufacturer’s recommendations and
                         the suggested waterproofing guidelines for the EIFS systems presented in Chap. 3.
                            Remedial repairs that do not require complete replacement of the system should first
                         begin with any required structural repairs. Then the new EIFS system should be applied as
                         a patch to the envelope areas that are removed to gain access for the structural repairs.
                            The existing EIFS system is then repaired, generally using elastomeric coatings to
                         create a barrier waterproofing system on the entire envelope. If repairing a divertor EIFS
                         system, the elastomeric coating must be permeable to ensure that moisture vapor can
                         escape back out to the exterior. All existing cracks in the EIFS system must be repaired
                         using the same techniques described for elastomeric coatings, including the overband-
                         ing of minor cracking and the sealing of larger cracks with a coating-compatible, low-
                         modulus sealant.
                            Since the majority of transition and termination details in EIFS systems are based on
                         sealant joints, all existing details must be carefully examined and repaired or replaced as
                         necessary. If expansion and control joints have failed because of adhesion problems, they
                         should be completely removed and replaced with a low-modulus urethane or silicone
                         sealant. If the joint was originally recessed, it is possible to perform repairs by over-
                         banding the sealant using a silicone sealant with appropriate bond breaker tape as shown
                         in Fig. 8.55.
                            Sealant overbanding can also repair existing joints that are flush with the surface,
                         as detailed in Fig. 8.56, which is similar to the previously described overbanding joint
                         repair.  This technique is also applicable in situations where the existing joint is
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