Renewing bathroom silicone joints
Difficulty: Medium · Time: approx. 45 minutes
An old silicone joint that's yellowed, cracked or mouldy doesn't just look bad – eventually it lets water through. Renewing it is very doable, but it takes care and patience when smoothing.
Most of it is preparation: removing the old silicone completely and working cleanly. Allow drying time – the new joint should cure for 24 hours before it gets wet.
What you'll need
- Utility knife or joint scraper
- Sanitary silicone (mould-resistant) + a caulking gun
- Masking tape
- Smoothing agent or a little soapy water
- Cloth + a joint smoother (or a clean finger)
Step by step
- 1
Remove the old silicone
Cut into the old joint on both sides with the knife and peel it off. Remove residue with the scraper – the surface must be completely clean, or the new silicone won't hold.
- 2
Clean and dry
Clean the joint thoroughly, remove any mould residue, then let it dry completely. Moisture is the most common reason joints go mouldy.
- 3
Mask off
Stick a strip of masking tape on each side of the joint, evenly spaced. This gives a clean edge.
- 4
Apply the silicone
Cut the cartridge tip at an angle to the right size and press silicone into the joint in one even pass – better slightly too much than too little.
- 5
Smooth and pull the tape
Wet the joint with smoothing agent/soapy water and draw it smooth in one pass with a smoother or finger. Then pull off the tape IMMEDIATELY while the silicone is still wet. Cure for 24 hours.
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Upload a photo →Frequently asked questions
- How long does the new joint need to dry?
- Usually 24 hours before it gets wet again. The exact time is on the cartridge – thick joints take longer.
- Why won't my joint go smooth?
- Usually the smoothing agent is missing: without a wetted surface the silicone sticks to your finger and tears. Use soapy water or a dedicated agent and work in ONE pass.