In Ottawa, a gas furnace replacement typically costs between $4,500 and $9,500 installed in 2026, with most homeowners paying around $6,000 to $7,500 for a properly sized, high-efficiency unit. A basic 96% AFUE single-stage furnace in a straightforward swap runs roughly $4,500–$6,000, a two-stage unit lands around $6,000–$8,000, and a fully modulating variable-speed furnace with a smart thermostat can reach $8,500–$11,000. Electric furnaces are cheaper to install ($3,000–$5,500) but far more expensive to run on Ottawa's electricity rates. The furnace itself is only part of the bill — venting c...
The single biggest driver of your price is the furnace itself. In Ottawa for 2026, a 96% AFUE single-stage natural gas furnace installed runs about $4,500–$6,000 — the workhorse choice for a typical 1,500–2,000 sq ft home. A two-stage furnace, which runs on low fire most of the winter for quieter, more even heat, costs roughly $6,000–$8,000 installed. A modulating variable-speed furnace, the most comfortable and efficient option, runs about $8,500–$11,000 and pairs well with a communicating thermostat. Mid-efficiency (80% AFUE) furnaces are no longer permitted for most residential installs in Ontario, so essentially every replacement quote you receive will be a condensing high-efficiency unit. Electric furnaces install for $3,000–$5,500 but cost substantially more to operate than natural gas in Ottawa, making them a fit mainly for homes without a gas line. Propane and oil furnaces sit at $5,500–$9,000 installed and are common in rural areas around Manotick, Osgoode, and Carp.
Most Ottawa homes need a 60,000–100,000 BTU furnace. Moving up from a 60,000 BTU to a 100,000 BTU unit typically adds $400–$900 to the equipment cost. Proper sizing comes from a heat-loss calculation, not from matching the old unit's nameplate — older homes that have since been insulated or had windows replaced often need a smaller furnace than what's being removed.
A complete Ottawa furnace replacement quote should cover far more than the box in the basement. Standard inclusions are the furnace, removal and disposal of the old unit, a new gas connection and shut-off at the appliance, sheet-metal transitions to your existing plenum and return, condensate drain and pump if needed, PVC intake and exhaust venting through the sidewall, a programmable thermostat, the City of Ottawa mechanical permit, and full commissioning with a combustion and gas-leak test. Labour typically represents $1,200–$2,500 of the total, usually a one-day job for a straightforward swap and two days when ductwork or venting has to be rebuilt. Watch for quotes that exclude permits, disposal, or the thermostat — those omissions are how a low headline number turns into a higher final invoice. Ask for the make, model, AFUE rating, and BTU output in writing so you're comparing identical equipment across contractors rather than guessing.
The extras are where budgets get blown. Converting from an old mid-efficiency furnace that vented up a masonry chimney to a modern condensing unit means new PVC sidewall venting — budget $400–$1,200 — and if a gas water heater is left orphaned on that chimney, it usually needs a stainless liner at $800–$1,800. Older Ottawa homes in Westboro, Hintonburg, and Old Ottawa South frequently need ductwork modifications or a larger return air drop, adding $500–$2,500. Undersized or corroded gas piping may need upsizing at $300–$1,200. Tight basement access, low headroom, and narrow stairways in century homes add labour. Other common line items include a new high-efficiency filter cabinet ($200–$500), a whole-home humidifier ($400–$900 installed), a smart thermostat upgrade ($250–$600), and asbestos abatement around old duct tape or boiler remnants, which must be handled by a licensed abatement firm and can add $1,000 or more.
Replacing a furnace in a January cold snap costs more — after-hours rates, limited equipment availability, and temporary heat rentals can add $500–$1,500. If your furnace is 15+ years old, planning the swap for spring or early fall almost always saves money.
A furnace replacement in Ottawa requires a mechanical (HVAC) permit from the City of Ottawa, and the work must be performed by a licensed gas technician holding a TSSA G2 or G1 certification. Permit fees are modest — generally $150–$300 for a residential furnace — and a legitimate contractor will include the permit in the quote and arrange the inspection. Any electrical work associated with the install falls under the Ontario Electrical Safety Code and may require an ESA notification. Never accept an install from someone who suggests skipping the permit: unpermitted gas work can void your home insurance, complicate a future sale, and leave carbon monoxide risks unverified. Ontario also requires a working CO alarm adjacent to sleeping areas in any home with a fuel-burning appliance, and your installer should confirm this at commissioning. Ask to see the technician's TSSA card and the contractor's liability insurance and WSIB clearance before work begins.
A high-efficiency furnace at 96–98% AFUE will usually cut gas consumption 15–25% versus a 20-year-old unit running near 80%, which in an Ottawa winter translates to roughly $200–$450 a year on a typical Enbridge bill. That payback period matters when you're choosing between a base model and a premium one: the variable-speed upgrade buys comfort and quieter operation more than dramatic fuel savings. Many Ottawa HVAC contractors offer financing in the $80–$150 per month range on a mid-tier system, and manufacturer promotions in spring and fall frequently include free thermostats or extended labour warranties. Provincial and federal rebate programs for home heating change frequently, so confirm what's active at the time you buy rather than assuming a past program still applies. If you're weighing whether to stay with gas at all, a cold-climate heat pump paired with a gas furnace as backup is increasingly common in Ottawa and worth pricing side by side.
The ranges above are planning numbers — your actual price depends on your home. Get at least three written, itemized quotes from licensed Ottawa HVAC contractors, and insist each one includes an in-person assessment rather than a phone estimate. A proper visit means measuring your home for a heat-loss calculation, inspecting the existing venting and ductwork, checking gas line size, and looking at the electrical panel. Ask each contractor to list equipment make and model, BTU output and AFUE, venting work, permit, disposal, thermostat, warranty terms on both parts and labour, and the total installed price with HST. Be skeptical of any bid dramatically below the others — it usually signals a skipped permit, a builder-grade unit, or venting and duct work that will resurface as a change order. Comparing multiple itemized quotes is free and routinely saves Ottawa homeowners $1,000 or more on the same job.
A gas furnace replacement in Ottawa costs $4,500–$9,500 installed in 2026, with most homeowners paying $6,000–$7,500. A 96% AFUE single-stage unit runs $4,500–$6,000, two-stage $6,000–$8,000, and a modulating variable-speed furnace $8,500–$11,000 installed.
In Ottawa, the furnace equipment alone typically costs $2,500–$6,000 depending on size and staging, and the installed price lands between $4,500 and $9,500 once labour, venting, permits, thermostat, and removal of the old unit are included.
A straightforward like-for-like furnace replacement in Ottawa runs about $4,500–$6,500 and takes one day. If the job requires new sidewall venting, a chimney liner, ductwork changes, or gas line upsizing, expect $7,000–$10,000 or more.
Older homes in areas like Westboro, Hintonburg, and Old Ottawa South often need extra work: PVC sidewall venting ($400–$1,200), a chimney liner for an orphaned water heater ($800–$1,800), and duct or return-air modifications ($500–$2,500). Budget $7,000–$10,000 total.
Yes. A mechanical permit from the City of Ottawa is required, and the install must be done by a TSSA-certified G2 or G1 gas technician. Permit fees are usually $150–$300 and should be included in your contractor's quote. Unpermitted gas work can void home insurance.
Most gas furnaces last 15–20 years in Ottawa, though the long heating season shortens that for units that are oversized or poorly maintained. Once a furnace is past 15 years and needs a repair over $1,500, replacement is usually the better value.