Anti-mould resealing

Why you can’t clean it out

Once mould has grown into silicone, the black marks are inside the sealant, not just on the surface. Bleach may lighten them for a while, but they come back. The lasting fix is to cut the old bead out, treat the joint and lay new sealant. Our guide on cleaning black mould from silicone explains when cleaning is worth trying first.

What we use

We use anti-fungal sanitary silicone from Arbo and Everbuild in bathrooms and kitchens. It contains a fungicide that slows mould growth. No silicone is mould-proof forever in a steamy room with poor ventilation, but a well-prepared joint with the right product lasts far longer than an ordinary bead laid over old sealant.

A real job: Crossways, Three Bridges

In a 1950s terrace on Crossways in Three Bridges, Crawley, black mould kept coming back around the bath however often it was cleaned. Someone had sealed over the old sealant, so the mould was trapped underneath. We took both layers out, cleaned and dried the joint and resealed with Everbuild anti-fungal white silicone, in under three hours.

Keeping mould away

• Run the extractor fan or open a window during and after showers
• Wipe or squeegee the joints after use
• Clean with a mild bathroom cleaner rather than harsh sprays every day
• Leave the new sealant for its full cure time before it gets wet

See why sealant goes mouldy for more.

Mouldy sealant near you?

We fix mouldy sealant in baths, showers, basins, kitchens and wet rooms across London, the South East and Scotland. Tell us your postcode for a quick quote.

What it costs

Our mastic calculator gives a guide price straight away. The exact price depends on how much old sealant has to come out, mould, how many joints there are and whether anything else needs doing on the same visit. Call or email with a few details (photos help) and we’ll give you a clear quote before any work starts.