Indoor mould (fungus) is very common in humid areas and in homes that have damp areas such as basements. Mould may trigger symptoms, such as wheezing or coughing, or another allergic reaction, such as the rash of atopic dermatitis or the stuffy nose of allergic rhinitis. Substances that trigger these reactions are called allergens.
Mould can get into a building through open doorways, windows, vents, and heating and air conditioning systems. Mould in the air outside can also attach itself to clothing, shoes, bags, and pets and can be carried indoors. Mould will grow in places that have a lot of moisture, such as around leaky roofs, windows, or pipes, or flooded areas. Mould grows well on paper products, cardboard, ceiling tiles, and wood products. Mould can also grow in dust, paints, wallpaper, insulation, drywall, carpet, and fabrics.
- Control mould in your home.
- Clean bathroom surfaces with soap and water, mould-killing products, or liquid bleach mixed with water. If you have mould in your home, remove it with one of these methods. Use bleach with caution, because it may irritate your nose and lungs.
- Add a mould inhibitor product to paint that you use in the home.
- Store fireplace wood outside the home. Drying green firewood can contain mould spores.
- Check houseplants for mould. Repot or move them outside if the soil contains mould.
- Control moisture.
- Remove carpeting from rooms that may have a lot of moisture, such as the bathroom and basement.
- Inspect closets for items, such as shoes, that may retain moisture.
- Keep the house aired out and dry. This may be difficult in some seasons and some climates.
- Use an exhaust fan in bathrooms and the kitchen to vent excess moisture.
- Make sure your clothes dryer vents moist air to the outside.
- Use a dehumidifier or air conditioner during humid weather. Try to keep the humidity in the home below 50%. Moulds thrive in higher humidity. You can use a moisture or humidity meter to find out how humid it is in your home. Many hardware stores sell this device.
- Seal off or avoid damp areas, such as crawl spaces, attics, or basements. Use a dehumidifier to control mould growth in these areas. Try to avoid materials that have been stored in these areas.
- Repair any water-damaged areas from leaking roofs or basements. Also, check the areas under sinks and around other plumbing for leaks. These areas can be prime mould-growing areas.
Current as of:
February 18, 2021
Author: Healthwise Staff
E. Gregory Thompson MD - Internal Medicine
Adam Husney MD - Family Medicine
Martin J. Gabica MD - Family Medicine
Kathleen Romito MD - Family Medicine
Rohit K Katial MD - Allergy and Immunology
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