Opening windows to let in fresh air is a common practice, but an indoor air quality expert, Jenny Smith, warns that this simple act could inadvertently invite mould into your home. Smith, with her 45 years of experience in the HVAC industry and as the founder of Mould Consultancy, encountered a surprising issue during a client assessment. She noticed fungal spores on security fly screens, which she believes could lead to health issues for the child living in the house.
Smith explains that when windows are closed, moisture in the air condenses, creating an environment conducive to mould growth. This is especially problematic if the relative humidity in the room exceeds 60%. She emphasizes that it only takes 48 hours for mould to start growing, and once it begins, it can quickly spread.
To prevent this issue, Smith recommends regular cleaning of fly screens. She suggests using soapy water and a single-use microfibre cloth to clean them at least once a year, but more frequently if possible. This simple maintenance can significantly reduce the risk of mould infiltration.
Additionally, Smith advises homeowners to be vigilant about checking for water damage and dust on the exterior of their buildings. She recommends using a white cloth or paper towel to rub along the walls, and if it comes up dirty, it indicates the presence of dust, which can lead to mould growth. This proactive approach can help catch potential issues early.
However, Smith also highlights a less-considered factor: the humidity outside. If the humidity is higher outside than inside, opening windows can bring in more moisture than is beneficial. She suggests using a hygrometer to monitor both indoor and outdoor humidity levels. By comparing the readings, homeowners can make informed decisions about when to open windows, ensuring they do not contribute to mould growth.
Furthermore, Smith stresses the importance of proper air circulation when opening windows. She advises opening one window while keeping another closed to allow air to flow out of the house, preventing the spread of contaminants. This simple technique can help maintain a healthy indoor environment.
In conclusion, while opening windows is a common practice for improving indoor air quality, it requires careful consideration. By following Smith's recommendations, homeowners can mitigate the hidden mould risk and create a healthier living space. This includes regular cleaning of fly screens, monitoring humidity levels, and ensuring proper air circulation when opening windows.
