Mould

Mould can make your home uncomfortable and unhealthy, but there’s good news: you can prevent it, clean it, and keep it from coming back.

What is mould, and why does it grow?

Mould is a type of fungus that grows in damp areas. Outdoors, it helps break down leaves and wood. Inside, it can grow on walls, ceilings, carpets, and other surfaces if there’s too much moisture.

Common causes of mould:

• Leaks in your roof, walls, or plumbing

• Humidity from cooking, showering, or drying clothes indoors

• Poor airflow in damp spaces like basements or bathrooms

• Flooding or water damage

Mould spreads through tiny particles in the air. These can get into your home through windows, doors, or even on your clothes and pets.

How can you stop mould before it starts?

The best way to deal with mould is to stop it before it starts. Since mould needs moisture to grow, keeping your home dry is key.

Easy ways to prevent mould:

• Fix leaks in roofs, walls, or plumbing as soon as possible

• Use fans or open windows when cooking or showering

• Run a dehumidifier in damp areas, like your basement

• Clean your gutters regularly and make sure water drains away from your home

• Avoid drying clothes indoors, or use a room with good airflow

• Check for damp spots, especially in bathrooms and kitchens

How can you tell if you have mould?

Mould isn’t always easy to spot, but here are some signs to look for:

• Discolouration: Mould can appear as black, white, green, or orange patches.

• Musty smell: A strong, earthy smell could mean mould is growing.

• Damp spots: Water stains, condensation, or past flooding may lead to mould.

Can mould make you sick?

Mould doesn’t affect everyone the same way. Some people may not notice any symptoms, while others could experience:

• Itchy eyes, a runny nose, or a sore throat

• Coughing, wheezing, or trouble breathing

• Worsening asthma symptoms

People more sensitive to mould include:

• Children and seniors

• People with asthma, allergies, or breathing problems

If you think mould is making you sick, talk to your doctor.

What should you do if you find mould?

If you find mould, it’s important to clean it up and fix the moisture problem that caused it. Small areas (less than half a wall) can often be cleaned yourself. For bigger areas, call a professional.

What you’ll need to clean small areas:

• Safety glasses

• A disposable dust mask (an N95 mask works well)

• Gloves

• Soap and water (you don’t need bleach)

Steps to clean small areas:

1. Scrub washable surfaces with soap and water. Dry the area quickly with fans or a dehumidifier.

2. For drywall or similar materials, use a damp cloth with a little water and baking soda. Avoid using too much water.

3. Throw away cleaning supplies and damaged items, like mouldy carpets, that can’t be cleaned.

4. Fix the moisture problem, like repairing a leak or improving airflow.

When should you call a professional?

• If the mould covers a large area, like more than half a wall

• If mould is growing in your heating, ventilation, or air conditioning system

What should I do next?

Here’s a quick summary of what to do:

1. Check your home for mould: Look for damp spots, musty smells, or patches of discolouration.

2. Clean small areas safely: Use soap and water, and fix any moisture issues.

3. Call a professional for bigger problems: They can remove mould safely and keep it from spreading.

4. Keep mould away: Stay on top of leaks, humidity, and ventilation to prevent mould in the future

Additional information

Check out these resources for more information:

• Health Canada: Addressing Moisture and Mould in Your Home

• Canadian Mortgage and Housing Corporation: Mould in Housing

• Canadian Centre for Occupational Health and Safety: Indoor Air Quality