S3 BOND IT – Premium Sanitary Silicone Sealant

Bond It S3 is a sanitary grade silicone sealant formulated for sealing joints in bathrooms, kitchens and other areas where moisture is a constant presence. It contains a fungicide to resist mould growth, which means your neat bead around the shower tray or basin should stay looking clean rather than turning into a science experiment after six months.

This is a one-part, high modulus silicone. You apply it straight from the tube with no mixing required. The high modulus formulation means it cures to a firm, durable seal that handles movement in the joint without losing adhesion. It bonds strongly to the surfaces you actually encounter in bathroom and kitchen fitouts: ceramics, glass, melamine laminates, sanitary plastics, anodised aluminium and lacquered metals.

Where S3 Sanitary Silicone Works Best

The typical jobs for this sealant are exactly what you would expect from a sanitary silicone. Sealing around basins and sinks, bedding basins to vanity units, running a bead around shower trays and enclosures, and finishing off bath installations. It handles the damp, humid conditions in these areas without breaking down or losing its grip.

For waste outlet connections on sinks and baths, apply the sealant so it will be under compression once you tighten the connecting pipes. This gives you a watertight seal that actually stays watertight rather than one that relies entirely on the silicone doing all the work.

Colour Options and Coverage

S3 comes in clear, white and ivory to match most sanitary ware and worktop finishes. The 310ml cartridge fits standard skeleton guns and covers approximately 10 to 12 linear metres with a typical 6mm bead. That is enough for a full bathroom refit in most cases, though kitchens with long worktop runs might need a second tube.

One practical note if you are working with metallised plastic trims: test a small area first. Some metallised finishes can discolour when in contact with silicone, and discovering that halfway through a job is not ideal. A quick test in an inconspicuous spot takes thirty seconds and saves potential grief.

The fungal resistance built into the formula is worth understanding. It does not make the sealant bulletproof against all mould forever, but it significantly extends the time before any growth appears compared to standard silicones. In a well-ventilated bathroom with reasonable cleaning, you should get years of clean-looking joints. In a poorly ventilated en-suite that never sees an extractor fan, you are fighting a losing battle regardless of what sealant you use.

Bond It S3 cures through reaction with atmospheric moisture. Skin formation happens within about 10 to 15 minutes in normal conditions, with full cure taking 24 to 48 hours depending on joint depth and humidity. Do not run water over fresh sealant or ask the customer to use the shower before it has had time to cure properly.