Most mould remediation jobs in the GTA cost between $1,500 and $6,000. Small, surface-only problems can be under $1,000; a whole basement or attic can be $8,000 or more. The size of the affected area, the materials involved and the containment needed make the difference.
Typical price ranges (2026)
| Area | Typical cost* |
|---|---|
| Small area under 10 sq ft (window sill, behind a toilet) | $500 – $1,500 |
| Bathroom or single room, with some drywall removal | $1,500 – $4,000 |
| Attic roof sheathing | $2,500 – $7,500 |
| Finished basement with full containment | $4,000 – $10,000+ |
| Mould testing / air sampling (optional) | $300 – $800 |
*Before HST. Rebuild after removal (new drywall, insulation, paint) is extra.
What affects the price
- Size of the growth. Health Canada and IICRC S520 treat areas over about 10 sq ft (roughly 1 m²) as jobs for trained professionals with containment.
- Containment level. Sealed poly walls, a zippered entry and HEPA air scrubbers under negative pressure add cost — and they're what keeps spores from spreading through your home. See what that looks like in our basement containment project.
- Materials. Porous materials like drywall, insulation and carpet usually come out. Wood framing and sheathing can often be cleaned.
- Access. Attics and crawlspaces take longer and need full PPE. See our attic mould project.
- Older homes. Suspect materials (old floor tiles, plaster, pipe wrap) may need an asbestos test before anything is disturbed.
Don't skip the cause
Mould comes back if the moisture does. Every quote should include the cause — a leak, poor attic ventilation, a bathroom fan venting into the attic, high basement humidity — and what it takes to fix it.
Does insurance cover mould?
Usually only when the mould follows a sudden, covered event, like a burst pipe that wasn't found for a few days. Long-term humidity or condensation is typically excluded. We document what we find so you can ask your insurer with clear evidence.
How to compare quotes
- Is containment described (poly walls, HEPA air scrubbing, negative pressure)?
- Which materials will be removed, and which cleaned?
- Is the moisture source identified?
- Is there a clearance step — a visual check, and testing if you want it?
Learn more about our mould remediation service, or send the form for a straight answer on your situation.
https://stepcarerestore.com/guides/mould-remediation-cost-toronto/.