Weatherproofing is intended to keep rain and other environmental elements from entering a building. To achieve successful weatherproofing sealant joints, it is advised to design for these parameters:
- “Joint Movement”—Occurs as a result of: changes in material temperature, seismic movement, elastic frame shortening, creep, live load, concrete shrinkage, moisture-induced material movement, and inadequate joint design. Joint movements must be evaluated, designed for, and accommodated.
- “Movement Capability”—The ± percent value that indicates the amount of movement the sealant can take in extension (+) and compression (-) from its original cured joint width. Movement capability and expected joint movement must be coordinated.
- “Installation Tolerances”—Depending on the substrate materials the joint opening will have a ± tolerance for its designed width which must be considered when establishing width (e.g. for a joint width of 1/2 inch in a brick masonry wall the tolerance for its width could be ±1/8 inch or more).
- “Sealant Selection”—Select the appropriate polymeric type for the application; however, within a polymeric type there can be a wide range in performance capabilities and properties. All sealants in that type may not perform similarly; therefore, it is important to research product capabilities prior to use.
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