Mould Remediation in Ottawa
Find, contain, and remove mould at the source.
Mould remediation means finding the water feeding the growth, containing the area so spores do not spread, removing material that cannot be cleaned, and drying what is left. Mould and mold are the same word, Canadian and American spelling, and the job is identical either way. Health Canada publishes a size chart for deciding who does it: three patches or fewer totalling under one square metre is usually a homeowner job with the right mask and gloves. A single patch larger than three square metres needs a professional assessment first.
What we handle.
Mould thrives where moisture lingers, and painting over it never solves the problem. We locate the source, contain the affected area, and remove mould-damaged material safely so spores do not spread through the home. Then we treat and dry the space so it does not come back.
- Inspection to trace mould back to its moisture source
- Containment and safe removal of affected materials
- Air scrubbing and treatment of salvageable surfaces
- Guidance on fixing the leak or humidity that caused it
Everything the job covers.
Finding the water first
Mould is a moisture problem wearing a costume. Health Canada's residential guideline lists four usual causes: condensation from excessive humidity, lack of ventilation or low temperature; water leakage such as a broken pipe; water entering through a leaking roof or a cracked basement; and a flood. Its 2023 guide to addressing moisture and mould indoors adds that mould will begin to grow in an area with excessive moisture within 48 hours. We trace the source before scoping removal, because remediation that leaves the water in place is a repeat visit.
Containment sized to the job
The Environmental Abatement Council of Canada's mould abatement guideline, written to help meet duties under Ontario's Occupational Health and Safety Act, sets three levels by area. Under 10 square feet is small scale: dust suppression, a drop sheet, HVAC shut down. Ten to 100 square feet is medium and calls for a sealed polyethylene enclosure held under continuous negative pressure, a minimum of 5 Pascals and at least four air changes an hour. Over 100 square feet is large scale and needs a site-specific plan from a health and safety professional.
Removing what cannot be cleaned
Non-porous surfaces such as glass, tile, metal and vinyl can be washed. Porous material usually cannot: Health Canada says to discard mouldy fabrics, carpet and cushions, and that a mouldy mattress cannot be properly cleaned. On building materials the abatement guideline says to cut porous substrate such as drywall and ceiling tile back at least 30 cm past the edge of visible growth, because the edge you can see is not the edge of the colony. Sealing or painting over it is not a substitute, and Health Canada's markers of a qualified company include prioritising removal over sealing or chemical treatment.
Drying, then haul-away
Removal is not the end of it. Wet material has to leave the building and the structure has to be dried, and Health Canada recommends a dehumidifier wherever condensation shows on cold surfaces or relative humidity sits above 50 percent. Junk removal is our core service, so the bagged material, cut drywall and ruined carpet go on the same truck instead of waiting for a second contractor.
What we do not do, said plainly
We are a removal and cleanup crew. We are not indoor air quality consultants, we do not run clearance sampling, and we do not write the site-specific work plan a large-scale job needs. Health Canada suggests that where extensive cleanup involves structural elements, a separate firm handle the post-remediation clearance study. Where your job needs that, we will say so rather than quote around it.
Start to finish.
Tell us what you can see, and we size it
Call or text (613) 852-4059 and describe it, or send photos. Then we walk the space and size the affected area against Health Canada's chart and the abatement levels above. If you land in the small or medium band, that is work you can do yourself with an N95, goggles and gloves, which is Health Canada's own minimum kit, and we will tell you so.
Contain before anything is disturbed
Poly sheeting with taped seams, HVAC shut down and adjacent diffusers sealed, and negative pressure where the size calls for it. Disturbing mould without containment is how a bathroom problem becomes a whole-house problem.
Remove, clean, dry
Porous material comes out and is bagged at the work area, non-porous surfaces are washed and dried, then air movers and dehumidifiers run until the substrate is dry rather than until it looks dry.
Haul it out and hand you the moisture list
Everything removed leaves on our truck, the part most remediation quotes price separately. You also get the list of what was wet and why, because the leak, the grading or the humidity is what decides whether the mould comes back.
Ottawa basements make their own water
Two local cycles feed this. Through winter, warm indoor air meets cold surfaces at rim joists, window frames and uninsulated foundation walls, and condensation forms on the cold side. Health Canada's advice is to hold indoor relative humidity between 30 and 50 percent and run a dehumidifier as soon as condensation shows. Then in spring the melt arrives at a foundation that spent months freezing and thawing, and finds every crack that opened. One City of Ottawa rule is worth checking before you spend anything on the mould itself. Property Standards By-law No. 2013-416 requires roof drainage to discharge at least 1.2 metres, four feet, from the building where physically possible. A downspout emptying at the foundation is both a by-law issue and a standing invitation to the wet wall under the mould.
What drives the price.
Mould work is priced on the size of the affected area and the containment that size forces, not on the room it sits in. What moves the number: how many square feet of material are genuinely affected, whether the growth is on non-porous surfaces that can be washed or in porous material that has to come out, whether a sealed enclosure and negative pressure are required, how much drying the structure needs, and access, since a crawl space costs more in labour than an open basement wall. Budget separately for two things outside our quote: repairing the leak or humidity that caused the growth, and, on a large job, independent clearance work. We look at the space and quote it up front. Call (613) 852-4059.
Mould Remediation, answered.
Still unsure? Call or text (613) 852-4059 and we will tell you straight.
Often, yes. Health Canada's decision chart calls an area small when there are three patches or fewer totalling under one square metre, and says a small area can be cleaned by the occupant with proper precautions. Medium, meaning more than three patches or a total between one and three square metres, can usually still be do-it-yourself work, though an expert assessment is recommended. A single patch larger than three square metres needs a professional.
Health Canada's Residential Indoor Air Quality Guideline for moulds, published 2007-03-31, is explicit that its recommendations, control the humidity, repair the water damage, clean the mould thoroughly, apply regardless of the mould species found growing in the building. Colour is not a diagnosis. Identifying the strain does not change what has to be removed, and no strain makes it safe to leave.
In most situations Health Canada does not recommend testing the air for mould. An air test cannot predict health effects and usually says little about the cause of the damage. The exception it allows is narrow: where concerns remain unexplained after a proper visual inspection, especially with a history of flooding or leaks, a qualified professional may recommend a non-viable spore test to locate hidden growth in cavities. If a company leads with a test, ask what decision the result will change.
Health Canada's guidance says not to use bleach to clean up mould. The method it publishes for washable surfaces is a cloth with an unscented soap solution, then dried completely and quickly. Bleach also does nothing about the reason the mould is there. If the moisture stays, the growth comes back whatever you wiped it with, and porous material that absorbed water still has to come out.
Health Canada publishes the checklist, so use it on every quote you get, ours included. Ask what certification and training the company holds, since Health Canada names IICRC certification as one marker. Ask whether the liability insurance specifically covers mould removal, and ask to see it. Ask whether they remove damaged material or seal and chemically treat it, because Health Canada favours removal. And get the inspection and cleanup procedures in writing before work starts.
The City of Ottawa's Property Standards By-law No. 2013-416 is the lever. Section 19 requires interior floors, ceilings and walls to be kept free from dampness entering through an exterior wall, a roof, or a cellar, basement or crawl space floor. Its residential walls and ceilings section requires finishes to be free of holes, cracks, loose coverings, mould or other defects. The by-law text is published on ottawa.ca, and enforcement is a City matter, not a contractor one.
Where these facts come from
Two authorities answering two different questions. Health Canada sets the size chart, the 48 hour figure and the advice on what can be washed and what has to be discarded; the City's Property Standards By-law sets the dampness and roof drainage conditions a building is held to, and enforcing it is a City matter rather than a contractor one.
Need mould remediation?
Call or text for an up-front quote. Same-day and next-day service across Ottawa and Gatineau.