How to Reseal a Shower (UK DIY Guide)
Over time, shower sealant can crack, peel or develop mould. Failing silicone allows water to seep behind tiles and trays, potentially causing damp and structural damage.
This step-by-step UK DIY guide explains how to reseal a shower properly, what tools you need, and when it’s time to call a professional.
Tools You’ll Need
- Silicone sealant (bathroom, mould-resistant)
- Sealant gun
- Sealant removal tool or scraper
- Utility knife
- Masking tape
- Cloths or paper towels
Materials Required
- Mould remover spray
- Isopropyl alcohol or cleaning solution
- Warm soapy water
Step 1: Remove Old Silicone
Use a sealant removal tool or utility knife to carefully cut away old silicone.
Remove all visible sealant along the shower tray, wall joints and corners.
Ensure no residue remains, as new silicone won’t bond properly to old sealant.
Step 2: Clean and Dry the Area
Spray mould remover on affected areas.
Wipe thoroughly and allow the surface to dry completely.
Clean with alcohol to remove grease and residue.
The area must be fully dry before applying new sealant.
Step 3: Apply Masking Tape
Apply masking tape along both sides of the joint to create straight lines.
This helps achieve a neat finish.
Step 4: Apply New Silicone
Cut the nozzle at a 45-degree angle.
Apply steady pressure to the sealant gun.
Run a smooth bead along the joint.
Work in one continuous motion where possible.
Step 5: Smooth the Seal
Wet your finger with soapy water.
Gently smooth the silicone along the joint.
Remove masking tape immediately before the sealant skins over.
Allow to cure for at least 24 hours before using the shower.
Common Mistakes to Avoid
- Applying silicone over old sealant
- Sealing on damp surfaces
- Using non-bathroom silicone
- Leaving gaps in corners
- Using the shower before curing
Proper preparation is key to a long-lasting seal.
When to Call a Professional
You should consider professional help if:
- Tiles are loose
- Water is leaking into the floor below
- Shower tray is moving
- Mould keeps returning rapidly
- There is structural water damage
See our Shower Repair Cost Guide for typical UK pricing.