Why radon testing matters in Ottawa
Ottawa sits on a mix of Canadian Shield bedrock and clay soils, both of which can release radon gas that enters homes through foundation cracks, sump pits, and floor drains. Health Canada's cross-Canada survey found that a meaningful share of Ottawa-area homes exceed the 200 Bq/m³ action guideline — but radon levels vary house to house, even on the same street. Testing is the only way to know where yours stands.
Because radon is invisible, odourless, and tasteless, there is no way to guess. A neighbour's low result doesn't mean your home is safe, and a high result on your street doesn't mean yours is dangerous. Every home needs its own test.
Short-term vs long-term radon tests
There are two main types of radon test. A short-term test runs for 2–7 days and gives you a quick snapshot. It's useful when you need an answer fast — for a real-estate transaction or a renovation timeline — but radon fluctuates daily and with the seasons, so a short-term result is just a screening.
A long-term test runs for 91 days or more and gives the most accurate picture of your annual exposure. Health Canada recommends long-term testing in the lowest lived-in level of your home (typically a basement bedroom or family room). If a short-term test comes back near or above 200 Bq/m³, follow up with a long-term test to confirm.
Where to place the radon detector
Placement matters. The detector goes in the lowest lived-in level of your home — not a crawlspace or unfinished basement you rarely enter, but the room where you actually spend time. A basement bedroom or family room is ideal. Place it at least 20 cm from the wall, away from windows, doors, vents, direct sunlight, and sources of humidity like a dehumidifier or dryer.
Don't place it in a kitchen, bathroom, or laundry room — humidity and air movement skew results. And don't place it near a radon mitigation system fan or sump pit if you already have one. We help you position the detector correctly during setup.
Reading your results
Your lab report gives a number in becquerels per cubic metre (Bq/m³). Health Canada's guideline is 200 Bq/m³. Below that, no action is needed. Between 200 and 600 Bq/m³, mitigation is recommended within 2 years. Above 600 Bq/m³, mitigation is recommended within 1 year. The World Health Organization suggests considering action even below 200, because there is no truly safe radon level — lower is always better.
If your result is high, don't panic. Radon mitigation is proven, affordable, and fast. A properly installed sub-slab depressurization system reduces indoor radon by up to 99%. We'll walk you through your result and your options with no pressure.