Silicone and mastic sealants are used at selected joints and interfaces in a waterproofing system. They can accommodate movement and help close a detail, but they do not replace a continuous membrane or correct drainage. A sealant that repeatedly separates may point to movement, poor adhesion, an unsuitable joint shape, or a problem beyond the visible bead.
Assessment starts with the substrate, the width and condition of the joint, its exposure to water and the materials beside it. The old sealant may need removal and the surfaces may need preparation before a compatible replacement is selected. Where leakage continues, inspect the adjoining construction rather than sealing over the symptom. See Waterseal’s joint detailing service for the wider waterproofing context.
Sealant is part of the detail
Sealants help accommodate movement at joints and interfaces, but selection depends on the substrate, joint design, exposure and adjacent waterproofing materials. Preparation and the shape of the joint influence how the sealant performs. Product requirements should be checked for the specific detail.
Recurring separation or leakage may indicate movement, adhesion failure or an adjoining membrane defect. A repair scope should assess the condition of the joint and its surrounding construction before replacement. Applying material over a failed interface without preparation may leave the cause unresolved.
