Beware: the main causes of mould in your home

If you’ve found mould in your home, you don’t necessarily need to panic. Learn the main causes of mould, and what you can do to avoid it.

Moulds are organisms that are part of the fungi kingdom. They digest or “eat” the material they are growing on and break down decaying matter like plants, leaves, or even dead animals.

In nature, you’re likely to find mould in places like soil, wood, and decaying plants and animals. But within the home, mould is prone to grow in places like carpet, paper, clothes, leather, drywall, wood, insulation, and food.

In your house, the main requirement mould needs to flourish is moisture. Mould can be found growing just about anywhere, as long as there’s enough of a moisture source, and other things like oxygen and organic materials to provide it with the nutrients it needs.

Mould problems cannot develop in houses unless there is a moisture problem. The moisture accumulation might be due to humidity, condensation, or water intrusion from leaks, spills, or floods. Most moulds only require the right materials to be wet for about 24-48 hours before they start to grow.

Mould needs these conditions before it can begin to grow in a home:

• Mould spores
• A food source (like wood, drywall, cotton)
• Darkness (mould can't grow under ultraviolet light)
• Warmth (mould can't grow in freezing temperatures)
• Oxygen
• Moisture (like water leaks or humidity)
• Enough time (most moulds can begin to grow in 24-48 hours if the conditions are right)

Of all of these factors, moisture is the key. If your home has a humidity problem, it’s likely you have mould. Other causes of mould include leaking pipes, leaks in the roof, condensation, poor ventilation, wet clothes, a damp basement, flooding, and water in the house’s foundation.