Dufferin Mutual Insurance Company


What is mould?

"Mould" refers to naturally occurring, simple microscopic organisms that have existed for millions of years. There are thousands of different mould species, each a member of the kingdom Fungi.

Fungi are parasitic organisms that lack chlorophyll. They can often be identified visually as spots or fuzzy masses and include mould, yeast and mushrooms.

Mould requires three important components to grow:

  • Moisture
  • Heat (between 2 and 40 degrees Clesius)
  • An organic food source

MouldMould decomposes its host food source (organic matter), using it for moisture and nutrients to reproduce itself. Nutrients are then absorbed by long filament strands, which grow to form the "fuzz" you see with certain types of mould. The food source can be anything from drywall, ceiling tiles, carpet, insulation and draperies, to wood or paper.

Mould on the move

Mould is most commonly found outdoors but it is also found indoors. It reproduces through spores that can be air-, water-, or insect-borne and can settle on virtually any surface. Generally mould flourishes when there is little to no air movement; increased air movement results in less mould. Damage caused by indoor mould can be minimized if it is properly treated and removed at an early stage. Common indoor locations for mould include moist areas such as bathroom walls, wood window frames and basements. Mould can enter homes, offices and other buildings through open doors, air vents, windows, cracks and crevices, and can be carried indoors by pets or on shoes and clothing. Often, mould becomes air-borne when materials are disturbed during renovations. Building materials left outside in the rain are also prone to mould growth.

Is mould harmful?

All types of mould have the potential to cause health problems and many people are allergic to it. The severity of the health effects depends on the type or amount of mould and any pre-existing health problems. People with asthma or allergies are more susceptible to mould-related problems. Mould may be present all year long. Mould weakens its host food source and can cause structural damage to buildings. Mould can develop on organic materials if they remain wet for 24 to 48 hours. It is not the quantity of water, but the time the material has been exposed to water or moisture that determines the growth of mould. The effects of mould are not always harmful. There are many examples of the controlled use of mould in the everyday production of food. As yeast, mould is used in the production of red wine, bread and beer. In other forms, it is used to make cheese or yogurt. Used in science laboratories, mould initially led scientists to the discovery of penicillin and has since led to the development of other helpful medicines.

How can mould be controlled?

Controlling indoor moisture is the number one way to avoid mould and its possible health effects. Other ways you can avoid mould or reduce mould damage are as follows:

  • Do not overuse humidifiers and maintain the moisture level in your home between 30 - 50%.
  • Check your house for signs of water leaks at least once a year and repair leaky roofs, eaves troughs and pipes. Downspouts should be positioned to drain away from the house.
  • Have water damage attended to immediately by a professional. Mould growth can start in less than 48 hours.
  • Ensure that all kitchen and/or bathroom exhaust fans are clean and that they vent directly to the outside of your home. Remember to turn them on whenever you produce steam.
  • If you can smell mould, you probably have a mould problem. Identify the source of the odour and immediately have it attended to.
  • Clean and vacuum carpets and furniture frequently, and regularly flush basement floor drains and sump pumps.
  • Remove moisture-trapping carpets and wallpaper in high-humidity areas such as basements, bathrooms and kitchens.
  • Increase ventilation and allow for sufficient airflow, which prevents moisture from getting trapped.

You've got mould

It's your house. Work with your insurance adjuster to see that all mould is removed.

Mould grows quickly; your adjuster should make sure you have a contractor in your house promptly.

Follow these steps:1.  Hire a contractor.

  • Look for a restoration contractor who is properly trained and experienced in removing mould.

2. Remove the mould safely.

To protect you and your family and limit exposure to mould, the contractor must:

  • Seal the affected area off room the rest of your house
  • Exhaust air continuously from the affected area to the outside
  • Safely dispose of mouldy materials (e.g., by not carrying them through the house)
  • Avoid the use of chemical cleaners.

3. Check that the work is done.

Ensure the contractor inspects all areas to make sure there are no wet areas or mould left in your house, before you tell your adjuster you are satisfied. Ask yourself:

  • Do you see mould?
  • Do you smell mould?
  • Have all wet or mouldy items been properly cleaned and dried, or discarded if cleaning was not effective?


Act quickly! You should not live in a mouldy house.

Insurance Bureau of Canada

Insurance Bureau of Canada (IBC) is the voice of companies that insure the homes, cars and businesses of Canadians. Member insurance companies provide about 90% of the private property and casualty insurance sold in Canada.

To learn more about IBC, visit www.ibc.ca

802 Main St E Unit 4, Shelburne, Ontario. Canada. L9V 2Z4
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Fax: 519 925 3357
email: info@dufferinmutual.com
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