Fighting Mold — The Homeowners' Guide from CMHC- Series # 2-

What makes molds grow?

Molds will grow if we provide them with moisture and nutrients. If we keep things dry, molds do not grow.
High moisture levels can be the result of water coming in from the outside, through the floor, walls or roof; or from plumbing leaks; or moisture produced by the people living in the home, through daily activities like bathing, washing clothes or cooking. Water enters the building when there is a weakness or failure in the structure. Moisture accumulates within the home when there is not enough ventilation to expel that moisture.
Different kinds of molds grow on different materials. Certain kinds of molds like an extremely wet environment. Other kinds of molds may be growing even if no water can be seen. Dampness inside the material can be enough to allow them to grow.
Why are molds a concern?

Damage to materials is one concern. Materials get stained or discoloured, and over time they are ruined. Moldy paper and cardboard disintegrate over time. Fabrics are damaged. Continued mold growth can be indicative of moisture conditions favourable for growth of fungi that cause wood rot and structural damage.
When molds are growing inside the home, there may be health concerns. Molds release chemicals and spores.
Health experts indicate that, depending on the type of mold present in a home, the amount and degree of exposure, and the health condition of the occupant, the health effects of mold can range from being insignificant to causing allergic reactions and illness.
Pregnant women, infants, the elderly and those with health problems, such as respiratory disease or a weakened immune system, are more at risk when exposed to mold. Consult your family physician if you believe there is someone who may be at risk.
Is there a mold problem?

Molds are always found in the air outside and in all buildings. They come into the home in many ways - through open windows or doors, on clothing, pets, food or furniture. The problem starts when mold grows inside the home.
Some mold growing, for example on the window sill but not elsewhere, is not a cause of concern. You can clean the mold yourself. The presence of mold is a sign that there is too much moisture in your home - a situation which must be corrected.
Inspect the home to find the extent of the mold.
How can you tell if it is mold?

Discoloration
Discoloration is a sign of mold. However, all discoloration is not due to mold. Carpeting near baseboards, for example, can be stained by outdoor pollution entering the home. Stains or soot may also be caused by the smoke from burning candles or cigarettes.
Mold may be any colour: black, white, red, orange, yellow, blue or violet. Dab a drop of household bleach onto a suspected spot. If the stain loses its colour or disappears, it may be mold. If there is no change, it probably isn't mold.
Smell/Odour
Sometimes molds are hidden and cannot be seen. A musty or earthy smell often indicates the presence of molds. But a smell may not be present for all molds. Even when you don't notice a smell, wet spots, dampness or evidence of a water leak are indications of moisture problems and mold may follow.