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Comfort & Heating Savings Estimator

A broad range, with every assumption showing.

This is a conservative educational model, not an audit. If the range it produces looks uncomfortably wide, that is the honest answer to a question asked from a web form.

Roughly what you spend on space heating in a year, in dollars.


Enter a figure and a simple payback range appears. Leave it blank and none is calculated, because a payback period without a cost is a made-up number.

−2%0%+6%

Applies only to the five- and ten-year figures. The headline range contains no escalation.

In words

What the numbers above are saying

Enter an annual cost to see an estimated range. Nothing is calculated until you do.

Comfort, which is the part people notice

    Recommended next step

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    What could change this result

    • Weather. A mild winter and a severe one differ by more than most upgrades do.
    • Energy prices, which are set quarterly and not by us.
    • Thermostat behaviour, occupancy patterns and how many rooms you actually heat.
    • The condition and efficiency of your existing heating equipment.
    • How much of the leakage is actually reachable once someone is in the attic.
    • Ventilation changes that may be needed alongside the work.
    • Installation quality, which varies more between contractors than materials vary between brands.
    • Whether hidden conditions turn up and change the scope.
    • Whether the model's assumptions match your house at all.
    Estimator disclaimer

    This tool provides a broad educational estimate using user-entered information and general assumptions. It is not an energy audit, quote, rebate determination or guarantee. Actual results depend on weather, energy prices, occupant behaviour, existing equipment, building condition, ventilation, project scope and installation quality.

    The model

    How this calculator actually works.

    Every number the estimator uses lives in a single configuration file. Nothing is hidden inside the interface, and nothing is tuned to make a result look better than it is.

    Where energy goes in an average Canadian homeA single horizontal bar divided into five parts: space heating about 63 per cent, water heating about 17 per cent, appliances about 13 per cent, lighting about 4 per cent and space cooling about 2 per cent. Figures are national averages reported by Natural Resources Canada and describe energy use, not dollars spent.63.5%17.2%13.5%Space heatingWater heatingAppliancesLightingSpace coolingSHARE OF ENERGY USED — NATIONAL AVERAGE, NOT YOUR HOUSESource: Natural Resources Canada. Shares describe energy, not dollars — a house heated with cheap fuel and run on costlier electricity will show a different split on its bills.
    ReferenceThis is the figure the estimator uses for context in Path B, and the reason it asks you to check the assumption rather than accepting it silently.

    Savings bands, as a share of heating cost

    ScopeBand
    Attic insulation and preparation10–25%
    Targeted air sealing5–15%
    Basement or rim-joist improvement5–12%
    Attic plus air sealing15–30%
    Whole-envelope package18–35%

    Combined scopes use their own band. Percentages are never added together, because two measures treating the same heat loss do not each save it independently. A hard ceiling of 42% applies regardless of inputs.

    How your answers move the band

    • Home age. Older construction shifts the band up; a house built after 2010 shifts it down considerably.
    • Existing insulation. Deep, even insulation reduces what a top-up can add. Little or none increases it.
    • Draft severity. Weighted heavily for air-sealing scopes and lightly for basement-only work.
    • Treatment breadth. A first phase covering one area is modelled well below a broad treatment.
    • Uncertainty. Every “not sure” widens the range rather than narrowing it. This is the opposite of what a sales tool would do, and it is deliberate.
    Reference figures used for context

    Toronto heating degree days of about 3,520 (18 °C basis). Natural gas at roughly $0.42 per cubic metre all-in, electricity at about $0.175 per kilowatt-hour all-in. These are used to sanity-check what you enter and to provide context, never to overwrite your own numbers. Ontario energy rates are reset periodically and should be checked against your own bill.

    Programs

    Incentives, stated carefully.

    Programs, funding levels, eligible measures and required sequences change, sometimes at short notice, and eligibility is determined by the program administrators rather than by a contractor. Some pathways require a pre-retrofit home energy assessment before any work begins, so the order in which you do things can matter more than the work itself.

    The current sources worth reading are below. Information on this page was last checked in May 2026.

    Latchline is not affiliated with any of these organisations, is not an energy advisor, and does not conduct official EnerGuide evaluations.

    A number is not a plan.

    The Scope Planner turns what you have noticed into a preliminary scope, and will carry your estimator answers across for you.