Signs your bath sealant needs replacing

Signs you can see

• Black or pink mould that comes straight back after cleaning. Mould inside the sealant, not just on it, means the bead has absorbed moisture.
• Gaps or lifting edges. If the bead has pulled away from the bath or the tiles, it is no longer sealing.
• Cracks, splits or a hard, yellowed bead. Old silicone loses its flexibility.
• A bead that has shrunk or become thin and uneven.
• Gaps that open when the bath is full. A bath moves under the weight of water, so a joint that looks fine when empty can open when full.

Signs of water getting through

• Damp patches, staining or bubbling paint on the ceiling below.
• Water on the floor beside the bath after use.
• Tiles that have come loose or grout that has become soft at the bottom edge.
• Skirting or panels near the bath that are swollen or soft.
• A musty smell in the bathroom that does not clear with ventilation.

Quick checks

Run a fingernail or the back of a spoon along the bead. If it lifts off easily, it has failed. Look closely at the corners and at the end of the bath where the tap wall meets the bath, because that is where most failures start. Check around the tap and overflow for movement or leaks.

How long does bath sealant last?

There is no fixed lifespan. It depends on the product, how well it was applied, how often the bath is used and how well the room is ventilated. Replace it when it shows the signs above, not by the calendar.

What to do next

• If the sealant is only stained and still firmly stuck, clean it with a suitable mould remover and ventilate the room.
• If it is split, lifting or the mould is deep, replace it. Our guide to how to reseal a shower covers the same method for a bath, and for baths it is usual to fill the bath with water before sealing, as the bath is at its lowest position then.
• If there are signs of water damage, have an applicator check the area before sealing over it.

Get it done

A bath reseal is a short job. You can post it here with a photo of the worst area and a rough measurement, and up to three applicators who cover your area can respond. For more help see bathroom and kitchen resealing or silicone sealant replacement. Not sure whether the silicone you have is the right type? Read silicone vs. mastic.

Quick answers

Can I just clean mouldy sealant?

If the mould is only on the surface it may clean off. If it has gone through the bead it will keep coming back and the sealant should be replaced.

Is a gap between bath and wall always a sealant problem?

Often, but a gap can also mean the bath or wall has moved. If the gap is wide, or keeps reopening, ask an applicator to look at it.