How Calgary is built
- Before 1961 10%
- 1961–1990 38%
- 1991–2000 17%
- 2001 or later 36%
Why it matters in Calgary
In the Calgary area, 74% of households heat mainly with a forced-air furnace and 8% with a boiler and radiators; natural gas is the main heating energy for 73% of households and electricity for 13% (Statistics Canada, 2023).
The risk rises after air sealing: a tighter house plus a strong exhaust fan or dryer can pull exhaust back down a chimney. That's why advisors test for spillage during an evaluation and why it should be repeated after serious tightening.
The CO alarm rule in Alberta
Alberta requires CO alarms in new homes with a fuel-burning appliance or attached garage; for existing homes the province calls them highly recommended rather than mandatory.
What the check involves
- Worst-case depressurization: exhaust fans and the dryer on, doors set to make the appliance room as negative as it gets.
- A spillage and draft check at each appliance, with a CO reading.
- A plan if anything fails: often a sealed-combustion appliance or a fix to the venting, done by a licensed gas or oil technician.
Prairies Alberta, Saskatchewan and Manitoba
What this means in Calgary’s climate
Long, very cold, very dry winters: air sealing, radon testing and humidity balance lead.
Why it matters here: Checks that gas furnaces and water heaters vent safely in a tighter house.
Best timing: During the blower door visit, especially after air sealing.
- Check gas appliances after tightening. Most homes here burn natural gas. Air sealing can depressurize the house and pull exhaust back inside, so appliances need a combustion safety test and working CO alarms. Ask: Ask for a combustion safety test during the blower door visit, and again after air sealing.
What else homes in Calgary need →
Sources for this climate guide · checked October 26, 2026
- National Building Code of Canada 2020, climate data (NRC)
- Canadian Climate Normals 1991–2020 (ECCC)
- Keeping the Heat In (NRCan)
- Air-Source Heat Pump Sizing and Selection Guide (NRCan)
- Heating and Cooling With a Heat Pump (NRCan)
- Heat pumps, Canada Greener Homes (NRCan)
- Gas and heat pump hybrid systems (NRCan)
- Primary heating systems by household, Table 38-10-0286-01 (Statistics Canada)
- Electricity price comparison, April 2025 (Hydro-Québec)
- 2024 Cross-Canada Survey of Radon Exposure
- Guide for Radon Measurements in Homes (Health Canada)
- Canada's top weather stories of 2021 (ECCC)
- Canada's most impactful weather stories of 2024 (ECCC)
- Canada's top weather stories of 2025 (ECCC)
- Conditions for thermal scans, ASTM C1060 summary (Cx Associates)
- Canada's top weather stories of 2020 (ECCC)
NRCan-licensed service organizations serving Calgary
A service organization is a company that Natural Resources Canada (NRCan) licenses to deliver EnerGuide evaluations; its registered energy advisors do the home visit. Energy advisors check for combustion spillage during an evaluation; fixing a venting problem is work for a licensed gas or oil technician.
- Acacia Engineering
- All Season Inspection Profile
- AmeriSpec Profile
- Buildingexpert
- Clean Energy Solutions
- CoEfficient Building Science
- Energy Werx Profile
- EnerHome Consulting
- EnerQuality
- EnerSolution Profile
- EnerVision
- GETS Energy
- Green Canada Home Advisors Profile
- Green Think
- Isle Energy Consulting
- Map Energy
- Sensible Home Inspections
- The Energuy Profile
- VerdaTech Energy Management and Consulting
- Enerspec Energy Consulting and Home Inspections
- Homesol Building Solutions
- NRGwise (A1 NRGwise Consulting) Profile
- Air Barrier Canada
- Greenbrain Profile
- Enerhold Engineering Solutions
- The Home Inspectors Group Profile
Programs in Calgary
Combustion safety test in Calgary: common questions
Are CO alarms required in Calgary homes?
Alberta requires CO alarms in new homes with a fuel-burning appliance or attached garage; for existing homes the province calls them highly recommended rather than mandatory.
Who does combustion safety testing?
Energy advisors check for spillage during an EnerGuide evaluation. Repairs to venting or appliances are done by a licensed gas or oil technician.
I have CO alarms. Isn't that enough?
Alarms warn you once CO is already in the house. A spillage test finds a venting problem before it produces CO.