Silicone sealant is a critical component in any tiling or wetroom installation. Whether it’s in a shower enclosure, around a kitchen sink, or sealing a bath edge, a properly applied sealant bead acts as a flexible, waterproof barrier that prevents leaks, protects against mould, and maintains a clean finish.
Over time, however, silicone can degrade — becoming discoloured, cracked, or mould-infested. Even with regular cleaning, once the silicone begins to break down, the only true fix is to remove and replace it. Done properly, re-sealing provides long-term protection and dramatically improves the look of the tiled surface.
In this guide, the technical team at Quantum Group outlines the professional method for removing and replacing silicone sealant, including tips, tools, and recommended products from our latest range.
Why Replace Sealant?
Silicone sealant is exposed to moisture, movement, and daily wear, which makes it vulnerable over time. Common reasons to replace sealant include:
- Mould growth – particularly in bathrooms or showers
- Discolouration or staining
- Cracking or splitting due to age or improper application
- Poor adhesion to the surface (peeling away)
- Leaks around bathtubs, sinks, or worktops
A poor-quality seal or expired silicone can result in costly water damage beneath the surface, including rot, mildew, and tile debonding — all of which can be prevented with correct removal and reapplication.
What You’ll Need
Before starting, gather the following tools and products.
| Tool/Product | Purpose | Recommended Product |
| Sealant Remover | Softens old silicone | ProClean Resin-Off |
| Scraper/Utility Knife | Removes softened sealant | |
| Mould Remover | Kills spores and cleans surfaces | Lithofin KF Mildew-Away |
| Cloth & Gloves | Hygiene & application | |
| Methylated Spirits / Degreaser | Removes grime, ensures adhesion | Ultratile Xtreme Clean |
| Sealant Cartridge Gun | For even application | Manual or Power Gun |
| Silicone Sealant | Waterproof sealing | Ultratile ProSeal IT |
| Sealant Smoother Tool | Clean finish |
Step 1: Apply a Silicone Remover
Start by applying a specialist silicone remover such as ProClean Resin-Off, designed to break down and soften old sealant.
- Apply directly along the old bead of sealant
- Allow it to sit for the recommended time (typically 2–24 hours depending on thickness and product)
- The chemical process dissolves the polymer chains, making removal cleaner and easier
Tip: Avoid cheaper acetone-based removers — these can damage sensitive surfaces like acrylic or plastic.
Step 2: Remove the Old Sealant
Use a scraper tool or sharp utility knife to carefully cut through the top and bottom edges of the old silicone.
- Pull the softened bead away slowly, being careful not to gouge tiles or bathtubs
- Use a scraper to lift away residue and hidden bits from joints
- If the silicone resists removal, reapply the remover and wait another 30 minutes
Be especially gentle around acrylic baths or shower trays – these surfaces scratch easily.
Step 3: Eliminate Mould and Bacteria
Even after the silicone is removed, mould spores can linger in the tile joints and grout.
Spray the entire joint area a product such as Lithofin KF Mildew-Away, a fast-acting mould remover specially formulated for ceramic surfaces.
- Kills fungal spores, bacteria, and mildew
- Restores hygiene before new sealant is applied
- Let it sit for 10–15 minutes before rinsing clean
This step is crucial in preventing future mould growth under the new bead of silicone.
Step 4: Clean and Degrease the Area
Once the surface is dry, use methylated spirits or a product such as Ultratile Xtreme Clean to remove:
- Soap scum
- Body oils
- Detergent residues
- Leftover silicone remover
Even invisible residue can prevent silicone from bonding properly, leading to early failure or peeling. Use a lint-free cloth and allow the area to air dry completely before proceeding.
Step 5: Apply New Silicone Sealant
Now you’re ready to apply a professional-grade silicone, such as:
- Ultratile ProSeal IT – Premium mould-resistant sealant
- Available in translucent, white, grey, black, beige, and more
- Offers excellent adhesion, long-lasting flexibility, and anti-fungal properties
How to Apply:
- Cut the nozzle of the silicone cartridge at a 45° angle
- Insert into your manual or powered cartridge gun
- Apply steady, continuous pressure
- Follow the joint line without stopping — gaps may trap water
- For baths: fill with water before sealing to simulate weight and prevent future stress cracks
Precision is key — work slowly, and don’t over-apply.
Step 6: Smooth and Finish the Bead
Use a sealant smoother tool or silicone profiling kit to create a professional finish.
- Mist the area with a 50/50 mix of water and washing-up liquid to help the tool glide
- Run the tool along the bead, applying even pressure
- Wipe excess silicone with a clean cloth immediately
Step 7: Allow Proper Curing Time
Curing time depends on the silicone type and humidity, but most products recommend:
- 24 hours minimum before exposing to water
- Up to 48 hours for full cure in damp or cold environments
Avoid touching or disturbing the bead during this period to ensure full adhesion.
Expert Tips from Quantum Group
- Always use trade-grade silicone for wet areas — avoid DIY brands that may lack proper elasticity or mould resistance
- Use a matching colour for aesthetics
- Use a primer on porous substrates like concrete, if required by the sealant manufacturer
- Never apply new sealant over old — this traps mould and leads to quick failure
Quantum Group NI – Wholesale Sealant & Tiling Solutions
At Quantum Group NI, we supply trade-quality sealants, adhesives, waterproofing systems, and tiling accessories to showrooms, retailers, and merchants across the UK and Ireland.
Whether you’re replacing sealant in a home bathroom or sealing full commercial wetroom systems, we offer:
- Fast next-day delivery from two distribution centres
- Expert product guidance and support
- Complete ranges including tiles, trims, matting, silicone, grouts, and tools
Email: [email protected]
Call: +44 (0)28 7131 2064