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Mould growth at baseboard level in a Toronto home

Mould Remediation in Toronto

Mould inspection, containment, and removal for homes and businesses across Toronto. IICRC certified specialists.

647-563-9966 · Available 24/7

Mould removal and inspection in Toronto

Toronto's housing stock covers more than a century of construction, and each era has its own mould story. Victorian and Edwardian brick semis in Cabbagetown, Leslieville, and the Annex were built with balloon-frame walls that run continuously from foundation to attic. Moisture that enters at the basement level can travel upward inside the wall cavity, and mould can establish itself at multiple heights without any visible sign at the surface.

Post-war bungalows across the inner suburbs, many of which have since been finished in the basement by subsequent owners, present a different challenge. Bathroom exhaust fans in those finished spaces frequently terminate inside the floor joist cavity rather than venting outside. Warm, moist air gets trapped in the framing and mould follows over months and years. The July 2013 storm overwhelmed the combined sewer system in dozens of neighbourhoods simultaneously; homes that were flooded and mopped up but never professionally dried are still carrying that moisture in their wall cavities.

In Toronto's condo towers, balcony door seal failures and inadequate bathroom ventilation in older buildings create slow, chronic moisture sources that allow mould to establish itself long before anyone notices. We inspect for all of these scenarios, find the source, and remediate properly so it does not come back.

Cleaning mould without containment spreads it further

Disturbing mould without negative air pressure containment sends spores through your HVAC system and into every room. What starts as a contained problem becomes a whole-house one. Proper remediation requires the right equipment and training.

Our mould services in Toronto include

  • Mould inspection and visual assessment
  • Air quality and spore count testing
  • Containment with negative air pressure to prevent cross-contamination
  • Mould removal and disposal of contaminated material
  • Antimicrobial treatment with eco-friendly products
  • Attic mould assessment and remediation
  • Post-remediation clearance air testing
  • Residential houses, condominiums, and multi-unit buildings
Significant mould growth in corner of a Toronto basement wall

Think you have mould in Toronto?

Call us for an inspection. We find the source, scope the problem, and tell you what is needed.

647-563-9966

Mould is usually a consequence of water damage that was not fully dried. If you have had a recent flood or backup, see our water damage restoration in Toronto. To test the air quality before or after remediation, see our air quality testing service.

Questions from Toronto homeowners about mould

We found mould in our Victorian semi near Leslieville. Is that a different problem from a newer home?
In some ways, yes. Balloon-frame construction common in Victorian semis means wall cavities run continuously from the basement to the attic, so moisture that enters at the lower level can wick upward and mould can establish itself at multiple heights inside the same wall. Older plaster walls also absorb and release moisture differently than drywall. We account for this during inspection and adjust drying and treatment accordingly.
Our condo has mould around the exterior wall in the bedroom. What is causing that?
Exterior wall mould in a condo unit almost always traces back to one of two sources: a failed window or balcony door seal allowing water to enter the wall assembly, or a thermal bridge where cold outside air chills the interior wall surface below the dew point and condensation accumulates. Both need to be identified and fixed before remediation, otherwise the mould returns. We inspect both possibilities.
Our basement in the Junction has a persistent musty smell but we cannot see anything visible.
Smell without visible mould is common and usually means the growth is inside the wall cavity or under the flooring rather than on the surface. Post-war homes with finished basements often have mould established behind the drywall for years before anyone sees it. A moisture meter inspection will find the elevated readings that point to where it is growing.
Does the 2013 storm still matter? We bought the house in 2015.
If the previous owner had water in the basement during the 2013 storm and it was not professionally dried and inspected, mould that established itself then can still be present. Mould in a wall cavity does not disappear on its own. If you have noticed any smell or seen any staining since moving in, an inspection is worth doing regardless of how long ago the event occurred.
Do you offer post-remediation air testing in Toronto?
Yes. After remediation is complete we coordinate clearance air testing to confirm that spore counts in the affected area have returned to normal background levels. This is standard practice for insurance claims and provides independent confirmation that the work was done properly.

Mould problem in Toronto?

Call 647-563-9966 to talk to a certified mould specialist.

647-563-9966 Get a Free Assessment

Available 24/7 • Greater Toronto Area • Bills directly to insurance

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