The line of silicone where your bathtub meets the tiles is cracking. Maybe it is discoloured too — grey or black where it used to be white. You notice it, think you should do something about it, and then close the shower curtain so you do not have to look at it anymore.
Here is why it matters — and why fixing it yourself is simpler than it looks.
Why you should not ignore it
The silicone seal exists for one reason: to stop water from getting behind the tiles and into the wall cavity. When the seal cracks or separates, water from every shower finds its way through. Over months, this causes damp, mould inside the wall, and eventually damage to the substrate behind the tiles. By the time it is visible, the repair is expensive.
The silicone seal itself costs €5 to €8. The wall repair it prevents costs hundreds.
What you need
- Silicone remover (spray or gel) or a sharp utility knife
- Bathroom silicone sealant (white or clear — check the label says mould-resistant)
- Silicone gun (€6–12 at any hardware store)
- Blue painter's masking tape
- A damp finger or a silicone smoothing tool
- Clean, dry cloth
The repair
- Remove the old silicone completely. Use silicone remover spray, leave it for the recommended time, then scrape it off with a plastic scraper or the back of a knife. Get all of it — new silicone does not bond properly over old silicone.
- Clean the gap with a dry cloth and let it dry completely. If there is any mould, clean with a diluted bleach solution first and let it dry.
- Apply blue masking tape to both the tile surface and the bath edge, parallel to the gap, leaving the gap itself exposed. This gives you a clean line.
- Cut the nozzle of the silicone cartridge at a 45-degree angle — the opening should be about the width of the gap.
- Apply the silicone in one continuous bead along the length of the gap. Do not stop and start.
- Dip your finger in water and run it along the bead in one smooth stroke to press the silicone into the gap and smooth the surface.
- Remove the masking tape immediately, before the silicone skins. Pull it away at a 45-degree angle.
- Leave undisturbed for 24 hours before using the bath.
The result
A clean, properly sealed joint that will last three to five years. The whole process takes about ninety minutes, including drying time between steps. The full repair is documented in She Fixed It with photos for each stage.