How to Start in Canada

How to Start a Mould Remediation Business in Canada

Start a mould remediation business in Canada: no national mould licence, the voluntary IICRC certification clients and insurers check, the asbestos survey required before you disturb building materials, and the containment, safety, and documentation routines the work runs on.

Written October 26, 2026 · Edited November 8, 2026 · 19 min read

Applies in: across Canada

The short answer

There is no mould licence to apply for in Canada, and that changes what you are actually selling. With no licence to hold up, clients, insurers, and adjusters judge you on three things instead: a voluntary certification they can verify, a safety routine that follows the provincial rules, and a written record for every job. The work itself is narrower than most new operators expect. Mould grows where moisture sits, so the job is always two jobs: remove the growth, and find and fix the water that fed it. Clean the surface and leave the leak, and the mould comes back on the same wall. The other trap is the wall itself. Mould work often means cutting drywall, lifting flooring, or opening insulation, and in an older building those materials may contain asbestos. The survey that answers that question comes before the cutting starts, under rules that are written down province by province. Learn the size classes, earn the voluntary credential, set up the asbestos check, and document everything. That is the business.

Step 1: Learn what the work is, starting with Health Canada's size classes

Health Canada's guidance is the plain-language anchor for the whole trade, and clients can read it themselves, so your language should match it. Health Canada's mould page sets out the size classes and the cleaning precautions. Mould is classed by area:

  • Small: one to three patches, each less than 1 square metre (10 square feet).
  • Medium-sized: more than three patches, or patches greater than 1 square metre but less than 3 square metres (32 square feet).
  • Extensive: a patch larger than 3 square metres.

Small and medium areas can generally be cleaned by following the precautions Health Canada sets out: safety glasses or goggles, a disposable N95 respirator, household disposable gloves, isolating the area with plastic sheeting taped to the walls and ceiling, vacuuming with a HEPA vacuum cleaner before and after cleaning, and cleaning with water and dish detergent. There is no need to use bleach, and drywall should be cleaned with a damp cloth so it does not get wet. People who are susceptible should not be in the same room or near the area being cleaned. Health Canada says to consider professional help with extensive mould growth, and to seek professional help when a large area is involved or the mould comes back after a previous cleanup, which points to a moisture cause that was never corrected.

Two working rules follow from that guidance and should shape how you scope and talk about jobs. First, the moisture source is the job. Health Canada recommends controlling dampness indoors and cleaning up visible mould regardless of the type of mould present, and it lists the usual sources plainly: plumbing leaks, water getting in through cracks or leaks in the foundation, floor, walls, or roof, condensation on cold surfaces, flooding, and exhaust fans that do not work, are not vented outside, or are not used. Keep indoor relative humidity between 30% and 50%. If you cannot name the water source, say so, and do not promise the mould will not return. Second, do not sell certainty you do not have. Do not promise a home is mould-free, do not present yourself as giving health advice, and do not tell a client what a mould type means for their health. Your scope is the building: find the moisture, remove the growth, dry the structure, and leave a record.

Step 2: Get the voluntary certification, and never call it a licence

The credential to understand first is the IICRC Applied Microbial Remediation Technician, or AMRT. It is built on the ANSI/IICRC S520 Standard for Professional Mold Remediation, which is the industry standard of care document for mould remediation work. The S520 sets out conditions used across the trade: Condition 1 is a normal indoor environment with no treatment necessary, Condition 2 is settled spores dispersed from a contaminated area without active growth, and Condition 3 is actual mould growth, active or dormant, visible or hidden. Two companion credentials cover the jobs that arrive with the mould call: the Water Damage Restoration Technician credential, for water categories, extraction, and drying, and the Health and Safety Technician credential, for jobsite safety, protective equipment, and hazard recognition. A new operator who plans to take insurance work should expect adjusters to ask about these by their initials, and should be able to say what each one covers.

All of them are voluntary. No federal mould remediation regulation makes them a legal requirement, and none of them is a government licence. That distinction belongs in your quotes, your website, and your conversations with clients: describe the certification as voluntary and industry-issued, name the issuing body, and never let a course certificate read as government certification. The certification also does not replace the provincial safety rules in Step 3, which apply whether or not you hold a credential. Budget for the training from the certifying body's current schedule, because course fees and requirements change, and keep the certificate where a client or adjuster can see it.

Step 3: Set up the asbestos and hazardous-materials check before you disturb anything

This is the step that decides whether a mould job is a straightforward remediation or a regulated hazardous-materials job, and it must be settled before work starts. Mould remediation routinely involves handling, disturbing, or removing drywall, joint compound, ceiling texture, insulation, vinyl flooring, and pipe wrapping. In older buildings, those materials can contain asbestos, lead, or other hazardous substances. Two provincial regimes show how the duty is written, and both put the inspection and the written record ahead of the work:

  • Ontario: under O. Reg. 278/05, the owner must have an examination carried out to establish whether material likely to be handled, dealt with, disturbed, or removed is asbestos-containing material, before requesting tenders for demolition, alteration, or repair, or arranging or contracting for that work without tendering. Whether or not an examination was required, the owner must have a report prepared stating whether the material is asbestos-containing or is to be treated as such, describing its condition and whether it is friable or non-friable, and containing drawings, plans, or specifications showing where it is. The owner must give any prospective constructor a copy of the complete report. As the contractor coming onto that job, ask for the report, read it, and keep a copy with the job file. If there is no report and no examination, do not start cutting until the question is answered.
  • British Columbia: under section 20.112 of the Occupational Health and Safety Regulation, before work begins on demolition, salvage, or renovation, the employer or owner must ensure a qualified person inspects the site to identify asbestos-containing materials, lead, or other heavy metals or toxic, flammable, or explosive materials that may be handled, disturbed, or removed. The inspection results, including drawings, plans, or specifications showing the locations of hazardous substances, must be available at the worksite, and any hazardous materials found must be safely contained or removed. If hazardous materials are discovered during the work that the inspection did not identify, all work must cease until they are contained or removed. The asbestos survey is carried out by a qualified person holding a valid asbestos Level S certificate.

Other provinces have their own occupational health and safety rules for asbestos and designated substances. The working rule is the same everywhere: do not sand, drill, cut, scrape, or demolish suspect material to find out whether it is hazardous. Stop, get the survey or the report, and treat material as asbestos-containing until proven otherwise. Asbestos abatement itself is a separate regulated trade with its own training, notification, and disposal rules: a mould remediation business that finds asbestos should bring in the qualified abatement contractor or surveyor rather than improvising the removal inside a mould job. Keep the survey and the report with the job file permanently, because the next contractor, the insurer, and a future buyer may all ask for it.

Step 4: Register the business

The paperwork is the same as for any Canadian service business:

  • Structure: most operators start as sole proprietors and incorporate later, when revenue and liability justify it. If you trade under a name other than your own legal name, register that name provincially.
  • Ontario: registering a sole proprietorship under a business name costs $60 through the Ontario Business Registry and lasts five years. Operating under your own name does not require registration.
  • British Columbia: request name approval first ($30), then register the sole proprietorship ($40) using the name request number within 56 days, or the approval lapses.
  • CRA business number: free, and needed for payroll, import, and GST/HST accounts. Register for GST/HST once taxable supplies exceed $30,000 over four consecutive calendar quarters, or voluntarily before that.
  • BizPaL: the federal-provincial BizPaL service lists the permits and licences for a business by location and activity. Run it for each city you work in before you advertise, because it surfaces municipal requirements a provincial registration page never mentions.

Registration gives you a business number for tax purposes. It does not give you the right to do remediation work at any particular address, and it does not replace the safety and survey duties in Steps 2 and 3. A municipal business licence is a separate question, and some cities license general contractors, renovation work, or hazardous-materials work differently. Check each city's licensing page for the work you plan to do there, and get the answer in writing.

Step 5: Build the safety, containment, and equipment routine

The routine is what keeps spores out of the clean parts of the building and keeps workers safe, and it should be written down, used on every job, and reviewed after any job that goes wrong. The elements below come from Health Canada's guidance and the S520 approach, and they scale with the size class from Step 1:

  • Containment: isolate the work area with plastic sheeting taped to walls and ceiling to prevent the spread of dust and mould particles, shut down or seal HVAC openings into the work area so spores are not carried through the ductwork, and keep the contained area under a routine the crew follows every time, including how materials leave the containment without crossing clean rooms.
  • Protective equipment: safety glasses or goggles, gloves, and respiratory protection matched to the job. Small-area cleaning uses a disposable N95 respirator. Larger or more contaminated work needs a respirator programme, not just a better mask: medical evaluation, training in putting the respirator on and taking it off and caring for it, and a fit test that proves the seal on the person wearing it. Do not let a worker rely on a respirator that has never been fit-tested for that worker.
  • Cleaning and removal: HEPA-vacuum the area before and after cleaning, clean washable surfaces with water and unscented soap or dish detergent, and remove and dispose of porous materials that cannot be cleaned, such as saturated drywall and insulation, rather than painting over mould or sealing it in. Painting over mould does not stop the issue. Bag and seal contaminated material for disposal, and check the municipal disposal rules for the waste before the job starts, because contaminated building waste does not always go in the ordinary stream.
  • Drying and verification: dry the structure and confirm it is dry with a moisture meter before closing the wall back up. The moisture reading is part of the job record, not a courtesy. If the moisture source was a plumbing leak, a roof leak, or a failed exhaust fan, the repair that stops the water belongs in the scope or in a written referral to the trade that does it. Closing a wall over wet framing guarantees a return visit.
  • Chemical safety: any cleaning or antimicrobial product used on the job needs its WHMIS safety data sheet on site, its label directions followed, and its storage and disposal handled under the label. Do not mix products, do not use a product in a way its label forbids, and do not promise a client that a sprayed treatment prevents mould from returning. The prevention is the dry building, not the chemical.

Hire the first worker only when the routine is written and the equipment is bought. A new hire who learns containment by watching one job will improvise the second, and the second job is where containment fails.

Step 6: Get the work, and document it so the next job follows

Mould work arrives through four channels, and each one asks for different proof. Homeowners and landlords call after a leak, a flood, or a failed inspection. Property managers call when a tenant reports mould or a unit turns over with visible growth. Real estate transactions generate work when an inspection finds mould or moisture and the sale depends on a written remediation record. Insurance and restoration work arrives through adjusters and restoration contractors, and it asks for the most proof of all: certification, coverage, and a file that shows what was found, what was done, and what was verified.

The file is the marketing. For every job, keep one record that holds:

  • The initial inspection: where the mould was, the size class, photographs, moisture readings, the suspected water source, and whether the moisture source is fixed, scheduled, or referred out.
  • The survey position: the asbestos or hazardous-materials report or survey relied on, or the written note that no building materials were disturbed and no survey was required.
  • The scope in writing: what will be removed, what will be cleaned, what containment will be used, what happens to the waste, and what is excluded, including any rebuild work that belongs to another trade.
  • The work record: containment photographs, removal and cleaning notes, drying readings over time, and the final moisture readings before close-up.
  • The verification: a post-remediation check that the area is dry, the growth is removed, and the moisture source is addressed, with photographs. Say what was checked and what the readings were. Do not claim a health outcome, and do not present a routine air test as proof of safety.

Price by scope, not by the square metre alone. The factors are the size class, the containment and access, how much material must be removed rather than cleaned, the drying time, the disposal route, and the verification step. A quote that lists those factors reads as professional; a single flat figure for any mould job reads as a guess. State payment terms, the change-order rule for concealed growth found behind a wall, and what happens if asbestos is found mid-job, before work starts. Concealed contamination is common in this trade, and a client who agreed to the rule in writing accepts the pause, while a client who never heard it argues about the bill.

What not to do

  • Do not start cutting, demolishing, or removing building materials in an older building until the asbestos and hazardous-materials question is answered in writing.
  • Do not advertise a voluntary certification as a licence, and do not claim a course certificate is government certification.
  • Do not promise a home is mould-free, do not give health advice, and do not present routine air testing as proof that a home is safe.
  • Do not clean the surface and leave the leak. If the water source is not fixed, say so in writing.
  • Do not paint over mould, seal it behind a new wall, or close up wet framing.
  • Do not let a worker rely on a respirator that has not been fit-tested for that worker.
  • Do not take asbestos abatement work inside a mould job without the qualified surveyor and the regulated abatement procedure behind it.
  • Do not skip the written scope, the moisture readings, or the photographs because the client seems easy. The easy client is the one whose insurer asks for the file.
  • Do not give medical advice, and do not advise a client on a health condition. Refer health questions to the client's own clinician.

Related guides:

Starting a mould remediation business in Canada, in six steps

  1. Learn the size classesHealth Canada classes mould as small, medium-sized, or extensive by area. The class decides whether the work is a cleaning job or professional remediation, and it shapes every quote you write.
  2. Earn the voluntary certificationNo national mould licence exists. The IICRC AMRT credential, built on the S520 standard, is the voluntary certification insurers and clients ask for. It is not a licence.
  3. Set up the asbestos checkBefore you cut, demolish, or remove building materials, the material likely to be disturbed must be checked for asbestos under the provincial rules. In Ontario and British Columbia the check and the written report come before the work, not during it.
  4. Register the businessRegister a business name if you trade under one, get a CRA business number, and register for GST/HST once you cross the threshold.
  5. Build the safety and containment routineIsolation with plastic sheeting, HEPA vacuuming, protective equipment, and a fit-tested respirator programme for larger work. The routine is the same on every job, not improvised per job.
  6. Document every job for the insurerMoisture readings, photographs, scope, containment, drying records, and verification. The file you hand over is what gets the next referral.

Official registration figures used in this guide

Ontario sole proprietorship registration$60, five years
BC name request plus registration$30 plus $40
CRA business number$0 — free
GST/HST registrationMandatory once taxable supplies pass $30,000 in a single calendar quarter or over four consecutive calendar quarters

No certification, insurance, or equipment figures are given in this guide, because they vary by provider and province. Price them from your own quotes.

Questions people ask

Do I need a licence to do mould remediation in Canada?

There is no national mould remediation licence in Canada, and no province issues a general mould licence. What does exist is a voluntary industry certification, provincial occupational health and safety law that governs the work, and separate rules for asbestos that apply when you disturb building materials. Anyone who tells a client they hold a government mould licence is misstating the position. Say plainly that your certification is voluntary and industry-issued, and point to the provincial safety rules you follow instead.

What certification should I get for mould remediation?

The credential insurers and adjusters most often ask about is the IICRC Applied Microbial Remediation Technician, or AMRT, which is built on the ANSI/IICRC S520 Standard for Professional Mold Remediation. The S520 is the industry standard of care document for the work. The Water Damage Restoration Technician and Health and Safety Technician credentials cover the water-loss and safety sides of the same jobs. All of these are voluntary certifications, not government licences. The first step on any microbial remediation project is to identify and eliminate the water source, so water-damage training matters as much as mould training.

When does mould work need professional remediation rather than cleaning?

[Health Canada classes the amount of mould as small](https://healthycanadians.gc.ca/environment-environnement/home-maison/mould-moisissures-eng.php) if there are one to three patches, each less than one square metre; medium-sized if there are more than three patches or patches greater than one square metre but less than three square metres; and extensive if a patch is larger than three square metres. Small and medium areas can generally be cleaned with protective equipment, a HEPA vacuum, and water and dish detergent, with no need for bleach. Health Canada says to consider professional help with extensive mould growth. Fixing the moisture source matters more than the cleaning itself: unless the cause is found and solved, mould will grow back.

Do I have to check for asbestos before mould remediation work?

Yes, when the work will handle, disturb, or remove building materials. In Ontario, [O. Reg. 278/05](https://www.ontario.ca/laws/regulation/r05278) requires the owner to have material likely to be disturbed examined for asbestos before requesting tenders or arranging demolition, alteration, or repair work, and to have a report prepared stating whether the material is asbestos-containing, describing its condition and friability, and showing its location, with a copy of the complete report given to a prospective constructor. In British Columbia, [section 20.112 of the Occupational Health and Safety Regulation](https://www.bclaws.gov.bc.ca/civix/document/id/loo65/loo65/296_97-20) requires the employer or owner to ensure a qualified person inspects the site to identify asbestos-containing materials, lead, and other hazardous materials before demolition, salvage, or renovation work begins, with the results available at the worksite. If hazardous material is found during the work that the inspection did not identify, all work must stop until it is contained or removed. Do not cut into suspect drywall, insulation, ceiling texture, or flooring in an older building until the survey question is answered.

Should I offer mould testing to clients?

Usually no, and Health Canada explains why: in most cases there is no need to measure the actual concentration of mould in indoor air or to determine the specific species. Find and fix the moisture and mould problems instead. Visible mould and evidence of moisture are normally enough to decide that corrective action is needed. Testing has a role when it answers a defined investigation question, such as unexplained concerns after an inspection or suspected concealed contamination. Do not sell routine air testing as proof that a home is safe, and do not present a test result as a health assessment.

What insurance does a mould remediation business need?

Ask a commercial broker about commercial general liability and workers' compensation coverage for your province before the first job, and ask specifically whether your general liability policy covers mould remediation work or whether separate pollution liability cover is needed. Insurers and adjusters are the source of much of this work, and they ask about coverage and certification before they refer jobs. Keep the answers in writing: the certificate, the policy wording on mould and pollution, and the workers' compensation account are part of the file a client or adjuster can ask to see.

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