Overview
- The guidance comes from Shutter Store specialists and is being relayed by UK outlets this week, with no change to official public-health policy.
- Opening a window after a hot shower can draw in colder outdoor air, causing rapid surface condensation and disrupting extractor-fan airflow.
- The World Health Organization identifies persistent dampness as the main driver of mould, a condition common in bathrooms.
- Reports cite bathrooms as two to three times more likely to harbour mould than bedrooms or living rooms, with humidity spiking to about 90% after showers and growth possible within 24–48 hours.
- Recommended practices include switching on the extractor fan before showering and leaving it running for about 30 minutes after, wiping down surfaces, cleaning the fan periodically, using moisture absorbers, and considering underfloor heating or mirror treatments.