Where exactly should carbon monoxide detectors go if I have a gas fireplace in a two-storey Ottawa home?

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Ottawa Fireplaces · Accepted Answer

Carbon monoxide detectors should be installed on every level of your home where someone sleeps or spends significant time, with specific priority placement near your gas fireplace and in bedrooms — this is not just a recommendation in Ontario, it is a legal requirement for homes with fuel-burning appliances, and it is genuinely lifesaving protection in a city where winter temperatures can trap carbon monoxide indoors for months at a time.

Why this matters in Ottawa specifically: Your gas fireplace is one of multiple potential CO sources in an Ottawa home — furnaces, water heaters, car exhaust from attached garages, and even improperly vented dryer exhausts can all produce carbon monoxide. The risk is amplified during Ottawa's long, brutally cold winters when homes are sealed tight, air exchangers may not be functioning optimally, and people spend 12 to 16 hours per day indoors. Carbon monoxide is odourless, colourless, and deadly — it binds to hemoglobin in your blood with an affinity 200 times stronger than oxygen, meaning your body's oxygen-carrying capacity drops dangerously while you feel almost nothing until it is too late. People have died in their sleep from carbon monoxide poisoning in Ottawa homes with faulty gas fireplaces or improper venting, and in every case, the tragedy was preventable with proper detectors.

Install carbon monoxide detectors in these specific locations: (1) Within 3 to 5 metres horizontally of your gas fireplace — this is the primary detection zone where CO concentration is highest if there is a problem. If your fireplace is in a living room or den, mount the detector on the wall at breathing height (4 to 6 feet above the floor) or on a shelf nearby. (2) In the hallway outside each bedroom on every level — this ensures the alarm will wake sleeping occupants if CO levels rise. Bedroom placement is critical because carbon monoxide poisoning progresses silently while people sleep; the alarm needs to sound before unconsciousness sets in. (3) On the main floor if your furnace is located there (basement furnaces also require bedroom-level detection, but main-floor placement covers the shared living space). (4) In the basement near your water heater or furnace if these appliances are fuel-burning. (5) On each level of a two-storey home — at minimum, one detector per storey, ideally two per level (one in bedrooms, one near the fireplace or furnace).

For a typical two-storey Ottawa home with a gas fireplace in the living room, the minimum acceptable setup is: one detector within 3 to 5 metres of the fireplace on the main floor, one detector in the upstairs hallway outside the primary bedroom, and optionally one additional detector in a second upstairs bedroom or hallway if your family spends significant time there. Many fire safety experts recommend going beyond the minimum — place detectors in every bedroom hallway and near every potential CO source. The detectors are inexpensive ($30 to $80 each), and a life is priceless.

Critical specifications for CO detectors: Purchase detectors that meet CSA (Canadian Standards Association) certification — look for the CSA mark on the packaging. Do not buy uncertified or imported detectors; they may not meet Ontario safety standards. Battery-powered detectors are acceptable, but hardwired detectors with battery backup are more reliable because they cannot be disabled by a missing battery. Test your detectors monthly by pressing the test button — if you do not hear the alarm, replace the batteries immediately or replace the unit if it fails the test. Replace all detectors every 7 to 10 years; they degrade over time and lose sensitivity. Mount detectors on walls or shelves at breathing height (4 to 6 feet for wall mounting, or on a shelf at similar height) — do not mount them on the ceiling or in corners where CO may not reach the sensor. Avoid mounting detectors in kitchens near gas stoves or in bathrooms with steam, as these can trigger false alarms.

Important warning signs that your gas fireplace may be producing dangerous CO levels: A yellow or orange flame instead of blue (indicates incomplete combustion), soot or discoloration around the fireplace or vent pipe, cold spots on the exterior vent pipe (suggests blockage or poor draft), intermittent smoke entering the room, or a smell of gas or combustion byproducts. If you notice any of these signs, stop using the fireplace immediately, turn off the gas, open windows, and call a TSSA-licensed gas fitter for emergency inspection. Do not try to troubleshoot a potentially dangerous gas appliance yourself.

Service and maintenance tie-in: Your gas fireplace should be professionally serviced annually by a TSSA-licensed gas fitter — ideally in early fall before you start using it regularly. A proper service includes checking the flame colour, verifying that the vent system is clear and properly sealed, testing for CO leakage, inspecting the burner assembly, and confirming that the appliance is ope

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