Why test the air quality in your home
The air inside a typical Canadian home is two to five times more polluted than the air outside, according to Health Canada — and most of those pollutants are invisible. Mold spores, radon gas, VOCs from building materials, formaldehyde from new furniture, particulates from cooking and combustion, and CO from gas appliances all sit at concentrations you cannot see, smell, or feel until they affect someone’s health.
A professional home air quality test identifies exactly what is in the air you are breathing, in what concentration, and where it is coming from. It gives you data — not guesses — to act on.
We have tested air in 15,000+ Canadian homes since 2005. The results almost always surprise homeowners: the worst contaminants are rarely the ones they were originally worried about.
Signs you need a home air quality test
Signs it’s time to test the air quality in your home:
- Persistent musty, chemical, or “off” odours that don’t clear with ventilation
- Visible mold spots, water staining, or recurring window condensation
- Respiratory or allergy symptoms that improve when you leave the house
- Recent renovation, new flooring, new furniture, or a flood / pipe burst
- You’re buying or selling a home and want a baseline before closing
- You live in a basement, slab-on-grade, or older home and have never tested for radon
What we test for in your home’s air
Signs it’s time to test the air quality in your home:
Mold spores. We collect spore-trap cassettes with a calibrated bioaerosol pump (Buck BioAire) and identify mold by genus at the lab — typically Stachybotrys, Aspergillus, Penicillium, Cladosporium and Alternaria. Spore counts indoors are compared to a simultaneous outdoor reference sample so we can tell whether the indoor air has an active mold source.
Radon gas. Radon is a naturally occurring radioactive gas from soil and rock; Health Canada’s action level is 200 Bq/m³. We can drop a long-term radon detector for 91+ days, or run a short-term grab sample if a faster result is needed.
Asbestos fibres. For homes built before 1990 or where vermiculite, popcorn ceilings or old vinyl flooring is being disturbed, we collect air samples on cassettes and analyze by phase-contrast microscopy or, if needed, transmission electron microscopy.
Volatile organic compounds (VOCs) and formaldehyde. Sorbent tubes or canisters capture VOCs from new furniture, paint, adhesives, cleaning products and combustion. The lab quantifies total VOCs (TVOC) and individual species by GC-MS. Formaldehyde is sampled separately on dinitrophenylhydrazine cartridges.
Particulate matter (PM2.5 and PM10). A laser particle counter measures airborne particles in real time. Sources include cooking, candles, fireplaces, smoking, pet dander, dust and outdoor pollution infiltrating the home.
Carbon monoxide and carbon dioxide. Continuous CO and CO2 sensors during the visit identify combustion-appliance leaks (gas furnaces, water heaters, fireplaces) and inadequate ventilation. CO above 9 ppm or CO2 sustained above 1,000 ppm both flag an issue worth investigating.
How air quality testing works
A professional residential air quality test in Canada follows four steps:
1. Consultation. A certified technician reviews your concerns by phone or in person and scopes which contaminants to test for. There is no point sampling for asbestos in a 2015 home, or for radon in a tenth-floor condo — we tailor the panel to your situation.
2. On-site air sampling. The technician arrives with calibrated equipment: a bioaerosol pump for mold spore traps, a particle counter for PM2.5 and PM10, and dedicated media for VOCs, formaldehyde, asbestos, or radon. The on-site visit takes 60–90 minutes for a typical Canadian home.
3. Accredited laboratory analysis. Samples ship the same day to an accredited Canadian laboratory. Mold cassettes are read by a microbiologist, VOC tubes by GC-MS, and asbestos by microscopy. Most panels return in 3–5 business days.
4. Report and action plan. You receive a written report with the raw lab data, a plain-English interpretation, comparison against published Canadian guidelines (Health Canada, ASHRAE 62.2), and recommended next steps — source removal, remediation, ventilation changes, or no action needed.
Professional vs DIY home air quality tests
Consumer air quality monitors (Airthings, uHoo, Awair, Atmotube) have come a long way. They are excellent for tracking daily CO2, PM2.5, basic VOCs and humidity in a single room, and at $200–$400 they are a worthwhile investment for ongoing awareness.
What they cannot do is identify a specific pathogen, certify a result for an insurer or real-estate transaction, or detect species or fibres that need a microscope. A consumer monitor can tell you “there is something in the air” — only a lab can tell you exactly what.
Here is when each makes sense:
| Situation | DIY consumer monitor | Professional lab test |
|---|---|---|
| Daily awareness of CO2, PM2.5, basic VOCs | ✓ best fit | overkill |
| Suspected mold problem | only flags “VOCs high” | ✓ identifies species + counts |
| Real estate transaction | not certified | ✓ accepted by lawyers, lenders |
| Post-renovation off-gassing | shows TVOC trend | ✓ identifies which compounds |
| Radon (long-term exposure risk) | a few monitors include it | ✓ Health Canada-grade detector |
| Asbestos suspicion | cannot detect | ✓ microscopy required |
| Insurance claim documentation | not accepted | ✓ accredited report |
Many of our clients run a consumer monitor between professional tests — the monitor flags a change, and the professional test identifies the cause. If you’d prefer to start with a DIY kit, we maintain a buying guide of the best air quality testing kits for Canadian homes.
Where we test — Ontario & Quebec service areas
Our technicians service homes across Ontario and Quebec from our Montreal and Ottawa hubs, with same-week appointments available in most service areas. We also offer remote-collection kits and partner referrals for cities outside our direct coverage.
Where we test — Ontario & Quebec service areas
Same-week appointments across our 8 primary service areas. Click a city for local details.
Outside these areas? Call 1-866-528-2897 — we offer remote-collection kits and partner referrals across Ontario and Quebec.
How much does residential air quality testing cost?
Residential air quality testing in Canada typically falls in the $300–$700 range, depending on how many sample locations you need (most homes are one or two rooms), which contaminant panels you choose (mold-only is cheapest; full multi-pollutant the most), and whether the laboratory analysis fees are included or billed separately. Multi-room and multi-contaminant tests scale up from there. Quotes are free — call 1-866-528-2897 or book a callback and we will scope a panel for your specific concern before any work begins.
Customer stories & reviews
Real feedback from recent residential air quality inspections across Ontario & Quebec
"We just moved into a 1970s house and wanted to be sure the air was safe before unpacking the kids' rooms. The technician walked us through every sample — what he was collecting, why, and what the lab would look for. Got the full report in four days, and the recommendations were genuinely actionable."
"My doctor recommended a professional air quality test to help manage my asthma. Three years on, the testing has paid for itself in fewer flare-ups — we found a hidden mold issue behind a basement vanity that no DIY monitor would have caught. Polite, thorough technicians who answer every question."
"Skeptical going in — the price was competitive but I half-expected a sales pitch. Got the opposite: technician spent an hour, packed up, said 'we'll see what the lab finds, you may not need anything done.' The lab found mild VOC elevation from new flooring; he recommended ventilation tweaks, no remediation, no upsell. Recommend without reservation."
"Persistent odours in the basement that wouldn't clear with ventilation. The team came out within the week, tested for mold and VOCs, and explained the lab report in plain English so I could share it with my insurer. They identified an old foundation crack as the moisture source. Five stars."
Mold assessment: how to tell if you have a mold problem
In addition to air quality testing, we also offer mold (mould) assessment services. This is a more general visual inspection of the area you believe is affected by mold. Because mold spores are microscopic, the main purpose of our mold inspections is to map the extent of contamination and identify the source — typically a moisture intrusion, condensation point, or hidden plumbing leak.
We use the assessment in two ways: to plan the mold remediation project and the prep work it requires, and to give you a clear, accurate quote.
Frequently Asked Questions
For most Canadian homeowners, a one-time test is enough unless something changes — new symptoms, a renovation, a flood or pipe burst, a new pet, or a real estate transaction. Health Canada recommends every home test for radon at least once (radon levels can change over years), and any home with a history of moisture issues should re-test for mold spores annually until the source is fully resolved.
The on-site visit takes 60–90 minutes for a typical Canadian home (longer for multi-storey or commercial buildings). Samples ship to the lab the same day. Most contaminant panels return results in 3–5 business days; rush turnaround is usually available for an additional fee. You receive a written report with raw lab data, a plain-English interpretation, and recommended next steps.
The most common signs reported in Health Canada’s IAQ guidance are headaches, fatigue, irritated eyes/nose/throat, congestion, worsening asthma or allergy symptoms indoors that improve when you leave the house, persistent musty or chemical odours, visible mold growth, and recurring condensation on windows. If symptoms cluster around a specific room or worsen seasonally, that room is the place to start sampling.
For a one-time consumer monitor used to track daily CO2 and PM levels — usually yes, they cost $200–$400 and give you ongoing peace of mind. For diagnosing a specific issue (suspected mold, persistent headaches, post-renovation off-gassing, real-estate due diligence, post-flood remediation), a professional test is worth several DIY kits because it produces a lab-certified report you can act on with a remediation contractor, an insurer, or in a real estate transaction.
A professional residential air quality test in Canada typically detects mold spores (by genus — Stachybotrys, Aspergillus, Penicillium, Cladosporium), particulate matter (PM2.5 and PM10), volatile organic compounds (VOCs), formaldehyde, carbon monoxide, carbon dioxide, and on request, asbestos fibres or radon gas. The exact panel depends on what concerns you — the technician scopes the test to your situation during the on-site visit.
You have two options: a DIY consumer monitor (Airthings, uHoo, Awair) for ongoing readings of CO2, PM2.5, VOCs and humidity, or a one-time professional inspection where a certified technician collects air samples with a calibrated pump and sends them to an accredited Canadian laboratory for analysis. DIY monitors are good for daily awareness; professional testing is what you want when you suspect a specific contaminant — mold, radon, asbestos, or unexplained symptoms — because the lab can identify and quantify exactly what’s in your air.