Andersen recommended silicone sealant 10.3 ounce tube. Sealants are elastic materials used to block the passage of water and or air while allowing movement between the two sides of the joint. A sealant should bond tightly and be able to expand and contract to accommodate joint movement without cracking or tearing away from the substrate. A general rule of thumb is the depth of the sealant joint should be equal to half the width (D=W/2), but generally not less than 1/4" or more than 1/2".
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