What should do I if I have Mould growth?

Treating mould in place or covering it up is not an industry-recommended practice.  If mould growth is identified indoors it should be removed.  If not, it can lead to a deterioration of building materials and may cause adverse health effects for susceptible building occupants.

Unless considered minor and because of the potential for adverse health effects, indoor mould growth should be removed by trained personnel using appropriate personal protective equipment (PPE) and control measures to prevent the spread of mould outside of the work area.  Although there are no regulations in Canada specific to mould, there are several reputable organizations that provide standards and guidelines for the assessment and remediation of mould contamination.  In general, the level of PPE and extent of control measures recommended by these standards and guidelines is based on the amount of mould growth present (and not the type of mould).

In addition to removing the mould, the underlying cause of mould growth needs to be determined and fixed.  Otherwise, there is a good chance that the mould will grow back.  There are many potential causes of mould growth.  A few common causes include:

• Poor building design or construction

• Leaks from water supply lines and associated appliances/fixtures

• Roof leaks or other building envelope failures

• Poor building or equipment maintenance

• A lack of or improper operation of ventilation, dehumidification or humidification equipment

• Tenant-related activities/hobbies (e.g., excessive indoor plants, fish tanks, cooking)

• Poor housekeeping

• Catastrophic events (e.g., floods, tornados, hurricanes, heavy rains, ice storms)