Mould in your house? Get rid of it
Wood. Drywall. Fabric. Dust. If any of these materials comes into contact with water or excess humidity for more than 48 hours, it will become an ideal medium for mould growth. Measures must be taken to eliminate mould, for the sake of the quality of the air in your home—and your health!
How to spot mould
There are many telltale signs of mould:
- Spots ranging in colour from pale green to black;
- Deposits that look “furry” or powdery;
- Webs of whitish filaments behind materials like wallpaper;
- An earthy or musty odour.
Locating the source and eliminating it
The presence of mould is directly linked to the presence of water: the cause may be water seeping in through the foundation walls or the roof, leaky plumbing, excess humidity, condensation due to a warm air leak inside a wall... Once the source is located and the problem is fixed, you must turn to cleaning or replacing the affected materials.
Who should do the work?
If the contaminated surface is less than 10 m2 (100 sq ft) and the mould was caused by clean water, you can do the work yourself. If you do, be sure to wear:
- a properly rated dust mask (N95 respirator or equivalent)
- safety glasses/goggles; and
- rubber gloves.
Make sure all other occupants of the home stay well away from the area to be cleaned. If need be, use vapour-barrier polyethylene sheeting to isolate the area from the rest of the house. Ensure there is negative pressure inside this enclosure, to keep the mould from spreading to other rooms. No person in fragile health should clean any surface contaminated by mould.
Keys to effective cleaning
Start by vacuuming the surfaces to be cleaned. To prevent fungal particles and spores from spreading to other areas of the house, make sure your vacuum cleaner has a HEPA filter (if you have a central vacuum, make sure it is externally exhausted). For the same reason, do not try to clean contaminated surfaces with a dry brush.
Excessively deteriorated materials, e.g., wood or drywall, must be removed, placed in bags or hermetically sealed containers, and disposed of safely.
The nature of the surface to be cleaned will determine the type of cleaner and cleaning method. If at all possible, avoid bleach and other chlorinated cleaning compounds (e.g., Javel water). They give off harmful fumes, so they should be used only as a last resort, and with caution.
Surface | Cleaning solution | Method |
|---|---|---|
Smooth, washable surfaces | Water and a mild, unscented detergent (e.g., dishwashing detergent), so that if odour returns, it will not be masked. | Scrub with a wet rag or wet sponge. Rinse. Allow to dry thoroughly. |
Drywall | Water and a mild detergent or baking soda. | Scrub with a wet rag or wet sponge. Do not over-moisten (the drywall facing is paper). Make sure the reverse side is untouched. |
Wood | Water and a mild, unscented detergent. | Scrub with a wet rag or wet sponge. Dry quickly. Sand, vacuuming away the resulting dust, if there are stubborn stains that do not come off with washing |
Concrete | Water and unscented soap. Large jobs: water and biodegradable trisodium phosphate (TSP) cleaner. | Moisten and brush surface, rinse and repeat as necessary. Caution: TSP is corrosive; ensure skin and eyes are well protected. |
All that remains is to ensure the room is well ventilated for as long as it takes for everything to dry completely.
What if mould reappears?
If there is a large amount of mould or the problem recurs despite multiple cleanings, or if the health of anyone in the house worsens, call in a specialist.
Mould and insurance
Damage resulting from gradual deterioration caused by mould is usually not covered by home insurance. You may be awarded compensation, however, if the mould was caused by sudden, accidental water damage that is covered by your insurer.