Dictionary of Moisture Protection & Restoration

III. SEALANTS The best barrier, drainage and diversion systems will not work if the transition joints are not properly installed. The majority of the failures are due to faulty joint installation or use of the wrong sealant. COMMON SEALANT COMPOSITIONS AND USES Acrylics: Factory mixed materials polymerized from acrylic acids. These are used frequently in remedial preparation work before the application of acrylic-based waterproofing coatings. They are available in brushable or trowel grades for use in preparing small cracks in substrates. Acrylic base sealants do not require primers and need minimal surface preparation. These have low movement capability. Do not use acrylic sealants in high-movement, vehicular and/or pedestrian joints or continuously submerged joints. Butyls: Sealants produced by polymerization of isobutylene and isoprene rubbers. These are the oldest technology in sealants. New technological advancements in better performing sealants have now limited their use to glazing windows or curtain walls with minimum movement. They have good adhesion and weathering capabilities. Butyls are easy to install, they are

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