New furnace prices in Ottawa and Ontario, 2026

Typical installed prices for an Ottawa-area house in 2026: a 96 percent AFUE single-stage gas furnace $4,800 to $6,300; a two-stage furnace $5,800 to $7,800; a modulating furnace with a variable-speed blower $7,400 to $9,900. Those are typical ranges, not quotes. The number for your house comes from a heat-loss calculation and a look at the basement, and the written quote is the one that counts.

What an installed price has to include

Compare furnace prices on what is inside them, because the cheapest number is usually the one with the most left out. An installed price should cover:

• The furnace itself, with the model number on the quote so you can look it up.
• Removal and disposal of the old unit.
• New intake and exhaust venting. A high-efficiency furnace vents in plastic pipe through the wall, not up the chimney, and the pipe, the terminations and the sealing are part of the job.
• The condensate drain, trap and, where it drains to a floor drain, a neutralizer.
• Sheet metal to connect the new cabinet to the old plenum and return.
• Gas connection, pressure test and the Ontario gas inspection.
• Start-up, combustion test and a thermostat that works with the furnace you bought.
• Warranty terms in writing: the manufacturer parts warranty and the installer labour warranty, which are two different things.

A quote missing any of these lines is not cheaper. It is incomplete.

Which tier fits which Ottawa house

The three tiers differ in how the burner runs. A single-stage furnace is either on at full output or off. A two-stage furnace runs at roughly two-thirds output most of the time and steps up only when the house is losing heat faster than that. A modulating furnace adjusts in small increments and pairs with a blower that does the same.

• A century home in Centretown, the Glebe or Old Ottawa South, with high ceilings, original windows and ductwork retrofitted decades ago, loses heat unevenly. A two-stage furnace with a variable-speed blower smooths that out better than a single-stage, and the longer, gentler cycles are kinder to old ducts.
• A 1960s bungalow in Alta Vista, Nepean or Gloucester is usually simple to heat: one floor, a straightforward duct run, moderate heat loss once the attic insulation has been topped up. A good single-stage 96 percent furnace, correctly sized, is often the right buy, and the money saved goes further on attic insulation.
• A 1990s to 2010s two-storey in Kanata, Barrhaven, Orléans or Stittsville usually has a bedroom floor that runs warm in summer and cool in winter. A two-stage furnace with a variable-speed blower helps, and if an air conditioner is also due, a hybrid heat pump on the same blower is worth pricing.
• A modulating furnace earns its price in a large or hard-to-heat house, or where someone in the house feels every temperature swing. In an average subdivision home the extra cost takes a long time to recover in gas.

Why Ottawa furnaces are sized differently

Furnace sizing starts from a design temperature, the outdoor cold the system must hold the house against. Ottawa's is around minus 25, well below Toronto's, so a house here needs more furnace than the same house would in southern Ontario. That does not mean bigger is safer. An oversized furnace heats the house in short bursts, satisfies the thermostat in minutes, shuts down, and does it again all night, which wears out the igniter and the blower and leaves the far bedrooms cold. The right size comes from a heat-loss calculation that measures the house: wall area, windows, insulation, air leakage, exposure. Copying the output off the old furnace label is a guess, and in Ottawa's older housing the old label is often wrong by a third.

The extras that move a quote

• Venting runs. A short run through the rim joist is included in the ranges above. A long run, a run through finished space, or a termination moved to a wall where it will not drift over costs a few hundred dollars more, and it is worth paying for in Ottawa.
• An orphaned chimney. If the water heater used to share the chimney with an 80 percent furnace, it may now be venting alone into a flue that is too big for it. A liner or a power-vented water heater is a separate line.
• Gas line. A furnace larger than the old one, or a propane home in Manotick, North Gower or the rural fringes, may need a larger supply or different orifices.
• Ductwork. Sealing and a new plenum are normal. Replacing an undersized trunk in a century home is a separate job and should be quoted separately.
• Electrical. A modulating furnace with a communicating thermostat sometimes needs a new thermostat cable.
• Permits. Furnace replacement in Ottawa needs the gas inspection; some duct and electrical work needs a city permit.

Reading three quotes side by side

Get each contractor to state the model number, the AFUE, the number of stages, the blower type, the warranty on parts and on labour, and whether removal, venting, condensate, inspection and start-up are included. Ask whether a heat-loss calculation was done and ask to see it. Three quotes for the same specification should sit within a thousand dollars or so of each other. One far below is missing something; one far above is charging for a brand name.

Buy in a month you choose

A furnace bought in February, on the night the old one quit, is the most expensive furnace there is: no time to compare, whatever the supplier has on the shelf, and no rebate paperwork. If your furnace is past fifteen years, price the replacement in September. The reasoning for that cut-off is in fix the furnace or replace it?, and what the current programs will contribute is in the rebates guide.

For a written installed price for your house, sized from a heat-loss calculation rather than the old label, ask for a furnace installation quote. If the furnace is still running and the question is whether it needs replacing at all, a repair visit gives you both numbers on the same trip.