Anti mould paints do not provide permanent prevention of mould growth. Period.
Anti mould paints do not address the root cause of black mould growth. Period.
Anti mould paints contain an active fungicidal agent that kills mould spores on contact. The problem is the agent does not last very long. So, when a surface is painted and new microscopic mould spores land on the newly painted surface they are killed but after a while when the agent wares off new spores are not killed and will start to grow again when indoor environmental conditions are favourable ie. during the colder months when indoor relative humidity increases.
In our experience, anti mould paints might provide some relief for up to 30 days but after that their effect starts to wane. Obviously if anti mould paint is applied in February you may not notice its effect has failed until the following September/October.
The only way to stop black mould growth is to address the root cause – the relative humidity condition.
