Tips & Tricks
How to Prepare Your Home for Extreme Weather
March 28, 2026 · 9 min read
Key Takeaways
- Seal air leaks around windows, doors, and electrical outlets before extreme cold hits
- Insulate exposed pipes and keep the thermostat above 16°C even when away
- Have your furnace serviced before the season — breakdowns spike during cold snaps
- Keep a power outage kit ready: flashlights, blankets, battery radio, and bottled water
Ontario winters can drop below -30°C with wind chill. Ice storms knock out power for days. Polar vortex events push furnaces to their absolute limits. Here's how to protect your home, your HVAC system, and your family when extreme weather hits the GTA.
Weatherproof Before It's Cold
Most heat loss happens through air leaks, not through walls. Check weatherstripping around doors and windows — if you can see daylight or feel a draft, replace it. Apply caulk around window frames and use foam gaskets behind electrical outlet covers on exterior walls. These $20 fixes can cut heating costs by 10–15%.
Insulate the attic hatch if it's just a loose piece of plywood. Add pipe insulation to any exposed pipes in unheated spaces — basement crawlspaces, garages, and exterior walls are the most vulnerable.
Get Your Furnace Ready
Extreme cold events push furnaces to run continuously for hours or days. A furnace that barely keeps up at -10°C will fail at -25°C if it's not operating at peak efficiency. Schedule a professional inspection that includes:
- Heat exchanger inspection: Cracks leak carbon monoxide — the risk increases under sustained heavy loads
- Blower motor and bearings: A marginal motor that works fine for 20 minutes will overheat during 8-hour continuous runs
- Flame sensor cleaning: A dirty flame sensor causes intermittent shutoffs — exactly when you need heat most
- Fresh filter: A clogged filter during extreme cold can trigger limit switch shutdowns from overheating
Prevent Frozen Pipes
Burst pipes cause more insurance claims in Ontario than any other winter event. When temperatures drop below -15°C:
- Open cabinet doors under sinks on exterior walls to let warm air circulate
- Let a pencil-thin stream of water run from the farthest faucet — moving water resists freezing
- Keep the thermostat at a minimum of 16°C, even when travelling. Set it to the same temperature day and night during extreme cold — setback schedules save money normally, but not during a polar vortex
- Disconnect and drain outdoor garden hoses. Close the interior shutoff valve for outdoor faucets
Prepare for Power Outages
Ice storms are the GTA's most common cause of extended power outages. Your gas furnace won't run without electricity — the blower motor, control board, and ignition system all need power. Here's what to have ready:
- Flashlights and battery radio: Don't rely on phones — battery life drops fast in cold houses
- Extra blankets and sleeping bags: A well-insulated house drops about 1°C per hour without heat. By hour 12, it's uncomfortable. By hour 24, pipes are at risk
- Bottled water: If pipes freeze, you lose water supply
- Portable phone charger: Full charge before the storm hits
- Generator (optional): A portable generator can run the furnace blower. Never run a generator indoors or in a garage — carbon monoxide kills. Place it outside, at least 6 metres from any door or window
Protect Your Outdoor HVAC Equipment
If you have a heat pump or AC condenser outside, clear snow and ice from around it after every storm. Ice buildup on a heat pump restricts airflow and forces the defrost cycle to run constantly — driving up your electricity bill and reducing output. Keep a 2-foot clearance around the unit.
Don't cover the AC condenser with a tarp or plastic — trapped moisture causes more corrosion than snow exposure. A breathable cover designed for outdoor units is fine.
During the Storm: What to Do
- Don't constantly adjust the thermostat: Set it and leave it. Frequent changes cause short-cycling
- Close rooms you're not using: Concentrate heat in living spaces
- Keep curtains closed at night, open during the day: Windows are a major heat loss surface. Solar gain during the day is free heat
- If the furnace stops working: Check the filter, thermostat batteries, and circuit breaker before calling for repair. If none of those fix it, call us at 1-855-539-4328 — we respond to emergency calls 24/7
After the Storm: Post-Event Checklist
Once temperatures normalize, walk through your home and check for water damage from condensation or minor pipe leaks. Clear any remaining ice from the outdoor HVAC unit. If your furnace ran continuously for several days, schedule a maintenance check — extended heavy use accelerates wear on blower motors and bearings.
Frequently Asked Questions
Should I turn up the thermostat before a cold snap?
Set it to your normal comfort temperature and leave it there. Cranking it to 25°C doesn't heat the house faster — the furnace puts out the same BTUs regardless. It just runs longer and overshoots once the cold snap passes.
My furnace runs constantly during extreme cold. Is that normal?
Yes, if it's maintaining temperature. During extreme cold, continuous running is expected. If the house temperature is dropping despite the furnace running, you likely have an undersized unit or significant air leaks that need addressing.
Do I need a whole-home generator?
It depends on your risk tolerance and budget. A whole-home standby generator ($5,000–$15,000 installed) starts automatically during outages. A portable generator ($500–$2,000) requires manual setup but can run the furnace blower and a few essentials. Either way, never run it indoors.
Be Ready Before the Weather Hits
Extreme weather preparation takes a weekend — recovery from an unprepared disaster takes weeks. Book a pre-winter inspection or call 1-855-539-4328 to ensure your system is ready for whatever Ontario throws at it.