Black mould in UK bathrooms can be eliminated permanently with a £1 silicone bath strip, according to silicone seal specialist Guy Chapman of United Silicones. The product works by creating a physical barrier over ageing sealant, stopping moisture from reaching the mould-prone area underneath.
Why Mould Returns Even in Summer
Many homeowners find black mould keeps returning despite regular cleaning. Guy Chapman explains that the root cause is microscopic water penetration behind the sealant. 'Standard bathroom sealant looks solid, but over time it shrinks, stiffens and pulls away from the bath edge by fractions of a millimetre,' he said. 'Moisture gets trapped behind it, creating the perfect dark, damp environment for mould spores to grow. Once that happens, surface cleaning is pointless – the mould just keeps coming back.'
Warm temperatures, steamy showers and poor ventilation create humid conditions mould needs to thrive, even during summer. By the time black stains appear, mould is often already growing behind ageing sealant, making surface cleaning ineffective.
How the £1 Silicone Strip Works
Rather than stripping old sealant or using harsh chemicals, Chapman recommends a self-adhesive silicone bath strip costing as little as £1. 'This works because it doesn’t rely on chemical resistance. Instead, it creates a physical barrier over the vulnerable joint, stopping water from reaching the damaged sealant underneath and preventing mould from taking hold,' he said.
Silicone strips last longer than traditional sealants because they do not shrink, crack or wear down over time. Once fitted, they form a waterproof barrier that keeps moisture out and prevents mould growth underneath. Unlike traditional sealants which cure, age and degrade, silicone strips remain flexible indefinitely, even with constant exposure to hot water.
Application Steps
To apply, first clean the bath edge and leave it to dry completely for at least 12 hours, as any trapped moisture can affect adhesion. Rather than removing old sealant, apply the silicone strip directly over it, pressing firmly along the joint to form a continuous waterproof barrier.
Chapman concluded: 'For less than the cost of a coffee, you’re stopping mould at the structural level. It’s one of the simplest preventative fixes in the home, and one of the most effective.'
