Silicone Sealant

A flexible, waterproof sealant applied around baths, showers, sinks, and other wet-area junctions to prevent water from penetrating behind surfaces.

Silicone sealant is a flexible, waterproof material used to seal the joints where different surfaces meet in wet areas — around baths, shower trays, sinks, worktops, and at internal tile corners. Unlike grout, silicone remains flexible after curing, which means it can absorb the slight movement that naturally occurs between different materials without cracking.

Where silicone sealant is used

  • Bath to wall junction — the seal between the top edge of the bath and the tiled wall above
  • Shower tray to wall — prevents water from leaking behind the shower enclosure
  • Sink to worktop — seals the joint where an undermount or drop-in sink meets the kitchen worktop
  • Worktop to wall — especially behind sinks and hobs where splashbacks meet the worktop
  • Internal tile corners — where two tiled walls meet, or where a tiled wall meets a tiled floor
  • Around window frames — on the interior where the frame meets the wall

Why silicone matters in a renovation

Poor silicone application is one of the most common causes of water damage in renovated bathrooms and kitchens. Water that gets behind tiles or bath panels can cause damp, mould, and structural damage to the underlying surfaces. It is a small detail that has outsized consequences when done badly.

Choosing the right silicone

  • Sanitary / anti-mould silicone — contains fungicides to resist mould growth. Essential for bathrooms and showers.
  • Kitchen silicone — food-safe formulation suitable for around sinks and worktops
  • Colour — available in white, clear, grey, black, and sometimes colours to match grout. Clear is versatile but can yellow over time in some products.
  • Quality — branded silicone from reputable manufacturers lasts significantly longer than cheap alternatives. This is one area where spending a little more on materials pays off.

When to check silicone during snagging

Silicone application quality is a key snagging item. Look for:

  • Consistent bead width with no gaps
  • Clean, straight edges (a professional will use masking tape)
  • No smearing on surrounding surfaces
  • Complete coverage with no missed sections
  • Properly cured (not tacky) before the area is used