How much does sealant replacement cost?

Internal sealant replacement — bathroom and kitchen

Internal silicone sealant replacement (shower tray, bath surround, basin, kitchen worktop upstand) is typically priced as a fixed job rather than per metre. Expect:

• Bath reseal (perimeter): £80–£150 depending on bath size and access
• Shower tray perimeter: £100–£180
• Kitchen worktop upstand run: £60–£120
• Full bathroom (bath + basin + shower + tiles): £200–£350

The main cost variable is whether the old sealant has been properly removed or whether it has been layered over previously. Layered sealant must be fully stripped before new material is applied — this adds time and therefore cost. A contractor who quotes to reseal without stripping the old material is adding a layer on top of a failed joint, which will fail again.

Materials used: low-modulus silicone with antifungal additives. Colour-matching to existing tiles or sanitary ware. We use mould-resistant grades as standard; cheap silicone is a false economy in wet environments.

External sealant replacement — windows, doors and perimeter joints

External sealant is typically priced per linear metre, with a minimum call-out charge applied for small jobs.

• External window sealant (perimeter): from £3–£6 per linear metre
• External door frame sealant: from £3–£6 per linear metre
• Movement joints, expansion joints: £4–£8 per linear metre
• Minimum call-out: applies to most jobs under approximately 15 metres total

The price variation comes from: joint width and depth (more material and prep time for wider joints), accessibility (ground floor vs upper floor — height adds cost), condition of the substrate (a clean joint takes less preparation than one where old sealant is bonded into a rough or friable surface), and the number of sides of the property affected.

For larger elevations or full perimeter treatments, we will quote a fixed price per visit after a site inspection.

What makes sealant replacement more expensive

• Previous layering — the single biggest cost variable. Old sealant bonded into a joint, especially silicone on silicone, must be removed mechanically. This is time-consuming on long runs or around detailed frames.
• Access — upper floor windows and doors may require ladder or platform. First-floor work typically adds 20–30% over ground-floor equivalent.
• Joint condition — a joint that has been repeatedly sealed, or where substrate has degraded, requires more preparation before new sealant will bond correctly.
• Matching — heritage properties and period features may need specific colour matching or specialist materials.

Internal or external — which failure is more serious

Internal sealant failure (mould, lifting edges, water getting behind tiles) is immediately visible and usually prompts quick action. External sealant failure is less visible but often more damaging — water getting behind external frames causes timber rot, wall saturation and internal damp that can take months to appear. If you have internal damp near a window or door, failed external sealant is the first thing to check.

What we include in every sealant replacement

• Full removal of existing sealant — no layering
• Surface preparation and substrate cleaning
• Correct material selection (internal vs external grade, low-modulus for movement joints, antifungal for wet areas)
• Neat, consistent finish
• No mess left on adjacent surfaces

We do not apply sealant on top of existing material. If the joint has been previously sealed and the old material is still present, it is removed before new sealant is applied.

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Get an accurate price for your job.

Every sealant job is different. Tell us what needs doing and we will give you a clear, honest price — no vague estimates.