Mould and Your Health
Home is where the heart is - it's where we spend time with family, friends and loved
ones. Because we spend much of our time at home, home is also where our health is.
That's why it's important to make sure that our homes are healthy environments.
The steps to make your home a healthy environment may not all come as a surprise
to you. But you may be surprised at just how much those little actions can help
On this page:
Take Action - Get Rid of Mould
Take Action - Prevent Mould
What are the Potential Health Risks of Mould?
There is a relationship between indoor mould, damp conditions and increased:
- Eye, nose and throat irritation
- Coughing and phlegm build-up
- Wheezing and shortness of breath
- Symptoms of asthma
- Allergic reactions
If you suspect that you or your family's health is being affected by mould, talk
to your health care provider as soon as possible.
People respond to mould in different ways, depending upon the amount of exposure
and the person's overall health. Some people are more vulnerable to the effects
of mould than others. This includes children, the elderly and those with a weakened
immune system or other medical condition(s), such as asthma, severe allergies or
other respiratory conditions.
What is Mould?
Mould is the common word for any fungus that grows on food or damp materials. Mould
can be black, white or almost any colour. It often looks like a stain or smudge
and it may smell musty.
In order to grow, mould needs moisture and a material it can live on. It then releases
"spores" into the air which are small enough that people can actually breathe them
in. Breathing in large amounts of these spores and the by-products they produce
can negatively impact your health.
Common places for mould to grow indoors are on window sills, fabrics, carpets, and
walls in kitchens, bathrooms, and laundry areas.
Recognizing mould is an important step in protecting your health and your family's
health. Check your home often.
Common sources of moisture
- Condensation on surfaces due to excessive humidity, lack of ventilation, or low
- Steam or excess moisture in the air from baths/showers and cooking
- Water leakage, such as from a roof or plumbing leak, a cracked basement, or flooding
Common household materials mould can live on
- Wood, such as window sills, wall framing and firewood
- Paper products such as cardboard boxes
- Damp materials such as carpeting or furniture
Find out if you have mould in your home. Check:
- The basement
- Under or behind stored items
- Under the kitchen or bathroom sink
- On the wall or floor next to the bathtub or shower
- At the bottom edge of windows
- Other damp places in your home
Not all mould is obvious. It can grow inside walls or above ceiling tiles. Check
for mould in damp places or where water damage has happened.
Take Action - Get Rid of Mould
What do I do if I find Mould?
Before beginning any mould clean-up take steps to ensure that you do not expose
yourself or others to mould spores. It is recommended that you wear an adequate
breathing mask (N95 or better respirator), safety glasses or goggles and rubber
Even with adequate precautions, mould spores may become airborne. As a precaution
during clean-up, children, the elderly and sensitive people such as those with asthma,
allergies or other health problems should leave the house. Consult your physician
if in doubt.
Clean up small areas
You can clean mould areas that are less than the size of a standard large garbage
bag folded in half (1 square meter). Follow these steps:
Find and fix the source.
Try to find and fix the causes of the mould. For example, a plumbing leak could
cause mould growth.
The source of moisture should be fixed to try to make sure the mould cannot grow
back once it's cleaned.
- Put on protective wear including a long sleeve shirt, appropriate and properly fitted
dust mask, safety glasses or goggles and rubber gloves. These items are generally
available in local stores.
- Prepare a bucket with water and a bit of dish detergent (preferably unscented) and
another with clean water. If you are cleaning drywall, you can use baking soda instead
of dish detergent.
- Clean the surface
- Wipe the surface with a rag dipped in the soapy water
- Sponge with a clean, damp rag and dry quickly
- Do not allow the drywall to get too wet
Replace porous or absorbent materials (such as ceiling tiles, upholstery and carpeting)
that become mouldy or are badly damaged. Dispose of the mouldy or damaged material appropriately.
Get Help with Larger Areas
Contact your housing manager or your local Environmental Health Officer (EHO) if
you suspect that your home has:
- One or more patches of mould larger than 1 square meter
- More than three patches of mould less than 1 square meter
- Patches of mould that keep coming back after cleaning
- A mould problem that you cannot solve on your own
If there is a lot of mould, (greater than 1 square meter), if mould comes back after
repeated cleanings, or if a family member suffers from asthma or other respiratory
problems as a result of mould, it is recommend that you contact your housing manager
or your local Environmental Health Officer (EHO) to obtain advice on the cleaning
of the mould in your house.
Take Action - Prevent Mould
How do I Prevent Mould?
Simple things that you can do:
When you see water or moisture act quickly
- Check home foundation, walls, windows, roof, plumbing, tubs and sinks for water
leaks. If you find a leak or a spill, dry the area and fix the leak.
- Check window sills regularly for condensation or moisture, particularly during the
cold months. If found, act quickly to dry the wet surface.
Ventilate your home
- Turn on an exhaust fan or open a window when showering or cooking. Let the fan run
for a few minutes after you are finished.
- Check clothes dryer, bathroom and kitchen fans, stoves, and oil or propane heaters
to be sure they are vented outside.
- Open windows, when practical. Use fans as needed.
Did you know
Controlling moisture and keeping your home dry is the key to preventing and stopping
Keep your home warm and ensure good air circulation.
- Rooms or areas that become cold can encourage condensation to form and surrounding
materials to become damp and mouldy.
- Keep furniture and other belongings away from exterior walls to allow warm air to
Remove items that may cause mould
- Reduce the amount of stored materials, especially in the basement and closets.
- Throw out wet and badly damaged or musty smelling items.
- Do not store firewood inside the home.
- Remove carpet in bathroom and basements that are damp.
- Avoid storing items in cardboard boxes on basement floors.
Keep your home clean and dry
- Clean and dry surfaces that get wet, such as:
- Drip pans in your air conditioner, refrigerator, and dehumidifier.
- Washing machine/tub, bathtub/shower, and surrounding walls.
- Vacuum carpets and furniture often.
- Keep drains in kitchen, bathroom and basement floor clear of debris.
- Use air conditioners and dehumidifiers during humid weather, if possible.
Minimize other indoor moisture sources
- Avoid hanging laundry to dry indoors when possible. Remove dryer lint after each
- Don't over-water plants and watch for signs of mould in the plants.
- Take out garbage regularly.
- Keep your sump pit covered.
Prevent water from entering your home
- Install downspout extensions to take rainwater and melted snow away from the home.
- Make sure eaves troughs/roof gutters and downspouts are connected and working. Clean
and repair regularly.
- Make sure the ground slopes away from the home foundation, so that water does not
collect around the foundation and enter the home.
"Mould in housing is one of the issues that can impact your health and your family's
health. Yes, when there's a lot of mould in a home, it's not a simple problem to
address and usually requires professional help. However, everyone has a role to
play in preventing mould and understanding what to do to clean up small areas and
how to get help with larger areas. Even the little things you do can help your health!"
Learn More About Mould