Resealing your bathroom is one of the most cost-effective ways to prevent expensive structural repairs. Over time, silicone sealant degrades, loses its elastici...
In the UK's damp climate, failing seals also become a breeding ground for black mould. A professional reseal not only refreshes the aesthetic of your suite but provides a vital waterproof barrier that protects your home’s integrity.
What Does the Work Involve?
- Survey and Assessment: Checking for movement in the bath or shower tray and identifying any underlying water damage or damp.
- Removal: Carefully slicing out the old, degraded silicone using specialised blades without scratching the bath or tiles.
- Surface Preparation: Applying chemical sealant remover to dissolve residue, followed by a fungicidal wash to kill deep-seated mould spores.
- Degreasing: Cleaning the joint with high-purity alcohol or methylated spirits to ensure the new silicone bonds perfectly.
- Application: Laying a continuous bead of high-quality, sanitary-grade silicone using a professional caulking gun.
- Tooling: Smoothing the bead to a consistent 45-degree angle to ensure water sheds away from the wall and into the basin or tray.
Typical Costs
Prices for bathroom resealing usually depend on the number of fixtures and the condition of the existing sealant. Most handyperson or plumbing services have a minimum call-out charge that covers the first hour of work.
| Item | Low £ | High £ | Notes |
|---|---|---|---|
| Standard Bath Reseal | £90 | £160 | Includes removal of old material and prep. |
| Shower Cubicle Reseal | £110 | £180 | Higher cost due to vertical joints and glass. |
| Full Bathroom (Bath, Shower, Sink) | £220 | £380 | Discounted rate for multiple areas. |
| Mould Remediation (Deep Clean) | £30 | £60 | Additional time for heavy staining. |
Factors affecting the price include your location (London and the South East are typically 20% higher), the type of sealant used, and whether any tiles need regrouting or repairing during the process.
How Long Does It Take?
- Standard Bath: 1.5 to 2 hours (allows for meticulous removal and cleaning).
- Large Shower Cubicle: 2 to 3 hours (more linear metres and intricate corners).
- Curing Time: 12 to 24 hours (the area must remain completely dry during this period).
DIY or Professional?
While sealant is cheap to buy, the skill lies in the preparation and the "finish." A DIY attempt often results in "smearing" or uneven beads that trap water rather than divert it. Professionals use industrial-grade anti-fungal silicones that last significantly longer than budget supermarket brands.
Note: If the resealing involves removing plumbing fixtures or if you suspect a leak has reached electrical circuits, you must hire a professional to ensure the area is safe and compliant with UK building standards.
Choosing the Right Tradesperson
- Look for Experience: Ask for photos of their previous "bead" work; it should be smooth, consistent, and clean.
- Check Reviews: Look for mentions of punctuality and cleanliness, as removing old silicone can be a messy process.
- Questions to Ask:
- Do you use "Sanitary Grade" Acetoxy or Neutral cure silicone?
- Will you fill the bath with water before sealing to account for weight-bearing movement?
- Is the removal of the old sealant included in the fixed price?
- What is the manufacturer's mould-resistance guarantee on the product you use?
UK Regulations
While there are no specific "Sealant Regulations," the work must comply with British Standard BS 6213, which provides guidance on the selection and application of sealants. For rental properties, the Homes (Fitness for Human Habitation) Act requires landlords to ensure bathrooms are free from serious damp and mould, making regular resealing a legal necessity.
Common Problems
- Applying Over Old Silicone: New silicone will not bond to old material, leading to immediate leaks.
- Sealing Damp Joints: If the joint isn't 100% dry before application, the sealant will peel off within weeks.
- Ignoring the "Gap": If the gap between the bath and wall is too wide (over 5mm), it may require a backing rod or trim before sealing.
- Poor Quality Silicone: Cheap sealants lack the high concentration of fungicide needed to prevent black mould in poorly ventilated UK bathrooms.
Frequently Asked Questions
How long should I wait before using the shower?
Most professional-grade silicones are "touch dry" in an hour, but you should wait a full 24 hours before exposing the seal to direct water spray or steam to ensure a deep cure.
Why does my new sealant have black spots already?
This usually happens if the mould spores weren't killed with a fungicidal wash before the new sealant was applied. It can also be caused by poor ventilation or leaving standing water on the seal after use.
Should the bath be full of water when it is sealed?
Yes. Filling the bath stretches the joint to its maximum width. If you seal it while empty, the first time you take a bath, the weight will pull the bath down and potentially tear the fresh seal.
Can I just put new silicone over the old stuff?
No. This is the most common cause of failure. Silicone does not adhere to silicone; the old layer must be completely removed and the surface cleaned with alcohol for a waterproof bond.
What is the difference between "Sanitary" and "General Purpose" silicone?
Sanitary silicone contains powerful fungicides (mould killers) specifically designed for high-humidity areas. General-purpose silicone will turn black very quickly in a bathroom environment.
This guide was written with AI assistance and is intended for general information only. Prices are estimates based on UK averages and may vary by region. Always get at least three quotes and consult a qualified professional before starting any work.
