Mould remediation in the GTA
Guardian Emergency Response performs containment-first mould remediation across the GTA, removing affected materials safely and correcting the moisture source so growth does not return.
When to call for mould
Visible growth, musty odours after a leak, or damp materials left wet for more than a day or two are signals to get a professional assessment.
Remediation approach
- Inspect — growth, moisture source, affected materials.
- Contain — isolate the zone and control airflow.
- Remove — controlled removal of contaminated materials.
- Clean & verify — HEPA cleaning where required; confirm dry conditions.
How big is the problem?
Health Canada sorts mould by area:
- Small: 1 to 3 patches, each under 1 m² (10 sq. ft.).
- Medium: more than 3 patches, or patches between 1 m² and 3 m² (32 sq. ft.).
- Extensive: a patch larger than 3 m².
Health Canada says small and medium areas can generally be cleaned by the homeowner with the right precautions. It suggests professional help for extensive growth, or when mould keeps coming back after cleaning. Large amounts of mould often point to a bigger problem, such as a foundation leak or a past flood.
Find and fix the moisture first
Health Canada notes that in most cases there is no need to measure the mould concentration in the air or identify the species. You need to find and fix the moisture problem. Remediation that skips the water source tends to come back. Health Canada recommends keeping indoor relative humidity between 30% and 50%.
Renting?
If you rent, speak to your landlord about mould. See Ontario rental water damage: tenant vs landlord and how to prevent mould after a flood.