Sealant failure in wet areas is almost always a selection issue rather than an application issue. Matching the sealant chemistry to the substrate and exposure is the first step.
Silicone sealants perform well for sanitary joints and glass-to-tile applications where flexibility and mould resistance matter most.
Polyurethane sealants suit structural and movement joints exposed to weather, offering stronger adhesion to concrete and masonry.
Hybrid polymer sealants are a good middle ground for facade and general wet-area work where paintability is also required.
Always check substrate compatibility and cure time before covering or tiling over a fresh sealant joint.