Drafty doors and windows in winter causing rising heating bills? Practical DIY leak sealing tips to save on heating costs

Every winter around Toronto, many people notice cold drafts near windows and doors; uneven room temperatures; heating running constantly with bills rising monthly. Usually no major work is needed; just seal air leaks and set the thermostat correctly. A few dollars and an afternoon can make a noticeable difference. This article covers what you can do yourself and when to call a pro.

Step 1: Find the drafts first

Invisible drafts cost the most. A few simple tricks can help you find them:

• Feel for drafts with the back of your hand: When it's cold, hold the back of your hand near door and window gaps, wall outlets, attic entrances, basement edges—if you feel cool air, it's leaking.
• Light an incense stick or candle: Hold a flame or smoke next to door and window cracks; where it flickers or bends is where air leaks (stay safe, keep away from curtains).
• During the day, turn off lights and check for gaps around doors: From inside, check around the door for any light showing through gaps—that’s where wind gets in.

Common draft spots: Gaps around the front door and under it, old window cracks, basement window wells, attic access, wall outlets, HVAC pipe wall penetrations, pet doors, mailbox openings。

Step 2: You can seal it yourself for a few bucks

Hardware stores (Home Depot, Canadian Tire, Dollarama) carry ready-made materials you can apply yourself:

• Door sweep: Install under front doors to block door gaps, usually the biggest source of drafts.
• Door and window weatherstripping: Self-adhesive foam or V-shaped strips applied where door or window frames meet. Replace when old strips harden or fall off.
• Window insulation film: Clear plastic film smooths out when heated with a hair dryer; adding a layer on old single-pane windows adds insulation and helps a lot in winter, peel off in spring with no residue.
• Insulating outlet pads: Remove the cover plate behind outdoor wall sockets and switches, insert a piece of foam padding, then reinstall the cover.
• Caulking: Seal fixed gaps between window frames and walls with caulk, only where it won't affect opening or closing.
• Temporary cold barrier: Use draft stoppers and heavy curtains in basement window wells and rarely used rooms.

Why is heating getting more expensive?

Besides air leaks, higher bills often relate to these issues:

• Dirty filter: Changing a Furnaces filter every 1–2 months when dirty reduces airflow and makes the furnace work harder. Thin filters replaced every 1–3 months is a cheap way to save.
• Thermostat set incorrectly: Keeping one high temperature all day wastes the most.
• Insufficient insulation: Thin or deteriorated attic and basement insulation causes heat loss from the top and edges.
• Furnaces worn out: Furnaces over 10-20 years old are less efficient, burn more fuel, and heat slower.

Adjust the thermostat for the most noticeable savings

• When home and awake, set atAround 20°C(Lowering by one or two degrees saves more if acceptable).
• No one home during sleep or work hours: Turn it down a few degrees(e.g. 17–18°C). Lowering the temperature by 1 degrees saves money over time.
• 用Programmable or smart thermostats, Set it to automatically adjust with your schedule so you don’t have to change it daily.
• 但Don’t lower the temperature too much just to save money: Keep temperature at least Above 13°C, Otherwise, pipes risk freezing and cracking (seePrevent frozen pipes）。

When to hire a professional

You can do sealing, change filters, and adjust thermostats yourself; for the following, hire a professional:

• Window replacement, door replacement: If old windows leak badly or fog between panes (seal failure), film is a temporary fix; replacement is needed (hire a Doors & Windows specialist).
• Add insulation or spray foam in the attic/basement: For large areas with dust and ventilation needs, hiring an insulation specialist is more effective.
• Furnaces maintenance or low efficiency: If it burns inefficiently, heats slowly or makes noise, have an HVAC technician check and service it (seeFurnaces maintenance) , Old furnace replacement can also be evaluated at the same timeFurnace Replacement cost）。
• Smell of gas: Leave immediately, go outside and call for repair; do not attempt to fix it yourself.

Is there any subsidy for Toronto?

Ontario and some energy companies occasionally offer energy upgrade programs (insulation, high-efficiency Furnaces/heat pumps, window replacement, etc.)Rebates or cashbackProjects and costs vary yearly. Check current official info (ontario.ca, your gas/electric provider) to see what's available and how much you can claim, Don’t blindly trust door-to-door sales pitches about “Fully government-subsidized”.

Seal air leaks, replace filters regularly, adjust the thermostat properly—most people will see lower bills this winter. When you need window replacement, extra insulation, or maintenance for Furnaces, post a request on LingGong.ca to get free quotes from nearby pros, then compare and choose.

FAQ

Do window insulation films really work?

For old single-pane or poorly sealed windows, applying film adds a layer of still air, blocks drafts, and reduces cold glass edges for a few dollars per roll lasting a winter; for new double-glazed, well-sealed windows, effect is minimal.

Is it more energy-efficient to keep the heater on continuously or only turn it on when needed?

For most households, Lower thermostat setting when asleep or awayMore savings than keeping a constant temperature all day, which is the point of a programmable thermostat. But don’t set it too low (keep above 13°C when away long to prevent freezing). Only consider lower and shut off water for true long-term vacancy.

If the windows in an old house are drafty, is it necessary to replace them?

Not necessarily. First, seal gaps with weatherstrips, draft stoppers, or insulation film—it often suffices. But if window frames are warped, sealed panes fogged (failed seals), or severe winter icing occurs, film is only a temporary fix. Replacing windows is more thorough, saves heating costs long-term. You can have window and door pros evaluate on-site.

Should you add insulation in the attic?

If upstairs is noticeably colder than downstairs in winter, Roofing tends to ice dam, or attic insulation is thin and compressed, adding thicker insulation is usually a cost-effective heating upgrade. For large dusty jobs, hire an insulation expert who can also check attic ventilation and air leaks around inspection hatches.