Ducted gas heating typically costs $4,000-$10,000 to replace when existing ductwork is usable, while a new system with ducts can reach $8,000-$18,000 or more. The final price depends on furnace capacity, efficiency, duct condition, labor rates, and local code requirements.
| Item | Low | Average | High | Notes |
|---|---|---|---|---|
| Furnace replacement | $4,000 | $6,500 | $10,000 | Installed, existing ducts reused |
| New furnace and ductwork | $8,000 | $12,500 | $18,000 | Typical home, new duct runs included |
| Furnace equipment | $1,500 | $3,500 | $6,500 | Price varies by size and efficiency |
| Duct installation | $2,000 | $4,500 | $8,000 | Whole-home work; layout affects price |
What a Typical Ducted Gas Furnace Costs to Install
A standard replacement in a 1,500-2,500-square-foot home often lands around $5,000-$8,000, including a midrange furnace, removal of the old unit, and connection to existing ducts. A smaller, basic system with straightforward access may cost $4,000-$5,500; larger or premium systems can exceed $10,000.
New ductwork changes the budget substantially. Installing a furnace and ducts throughout a home commonly totals $8,000-$18,000, with difficult renovations or extensive duct modifications potentially costing more. Assumptions: typical U.S. home, standard access, midrange equipment, and no major structural repairs.
For a like-for-like replacement, $6,500 is a useful planning average, not a guaranteed quote. Ask whether the estimate includes thermostat, venting, permits, startup testing, and haul-away.
How Equipment, Labor, And Ductwork Shape The Quote
Quotes often combine the furnace, installation labor, venting and gas connections, and any duct repairs. Costs overlap by project, so the table gives typical line-item ranges rather than a formula to add mechanically.
| Quote component | Typical price | Pricing basis | Common scope |
|---|---|---|---|
| Gas furnace | $1,500-$6,500 | Per unit | Capacity and efficiency drive equipment price |
| Installation labor | $1,200-$3,500 | Per job | Removal, fitting, connections, testing |
| Ductwork | $2,000-$8,000 | Whole home | New runs, returns, sealing, or replacement |
| Venting and gas work | $300-$1,500 | Per job | Flue changes or gas-line adjustments |
| Permit and disposal | $100-$600 | Per job | Local permit and old-equipment removal |
Labor commonly represents $75-$150 per technician-hour, though contractors usually quote a project total. Confirm that the written quote identifies included work and any allowances for duct repairs.
Furnace Size, AFUE Rating, And Duct Condition Change Prices
Capacity is usually measured in BTU per hour. A home needing roughly 40,000-80,000 BTU/hr may fit a common residential range, but a contractor should size the system from a heating-load calculation rather than square footage alone. Oversizing can raise the equipment price and lead to less comfortable cycling.
Basic furnaces often have 80% AFUE efficiency, while high-efficiency models commonly reach 95%-98% AFUE. Equipment and venting upgrades can add roughly $1,000-$3,000 over a basic option. Existing duct leakage or undersized returns may add $500-$2,500 for sealing and modifications; extensive replacement can cost several thousand dollars more.
Capacity, efficiency, and duct repairs are the three quote details most likely to explain a large price gap. A high-efficiency unit may also require different venting and condensate drainage, so the equipment price alone does not show the complete installed cost.
Why Installation Labor Takes Longer In Some Homes
A straightforward replacement often takes 6-10 hours for a two-person crew. A new ducted system, major duct revisions, or tight attic and crawlspace access may require 2-4 days. Labor rates and travel charges tend to be higher in dense metro areas than in many rural markets.
As a broad planning comparison, urban quotes may run 10%-20% above a regional baseline, while rural work can be 5%-15% lower when contractors are nearby and access is uncomplicated. Remote travel or limited contractor availability can reverse that difference. Check whether the proposed crew hours reflect the actual access and duct scope.
Three Ducted Heating Quotes With Different Scopes
These examples illustrate how equipment and site work affect totals; local labor and permit fees can shift the numbers.
| Scenario | Scope | Labor estimate | Installed total |
|---|---|---|---|
| Basic replacement | 60,000 BTU, 80% AFUE, reuse ducts | 8-10 hours | $4,800-$6,200 |
| Efficient upgrade | 80,000 BTU, 96% AFUE, vent changes | 10-14 hours | $7,000-$10,000 |
| New ducted installation | 70,000 BTU, new ducts in 1,800-sq-ft home | 2-4 days | $10,000-$16,000 |
Compare matching capacities and included duct work before treating the lowest total as the best value. An estimate that excludes venting or duct balancing may not be comparable to a complete installation quote.
Old Duct Removal And Code Work That Add Charges
Removing an old furnace is often included, but unusual disposal requirements can add $100-$400. Duct removal and replacement may add $1,000-$3,000 or more depending on access and how many runs are affected. A new flue, gas-line adjustment, electrical work, or condensate drain may add $200-$1,500 each, depending on the repair.
Permit fees commonly fall around $50-$300, but requirements vary by city and project. Some locations require inspection or updates to venting, combustion air, or gas connections. Request a written allowance for concealed problems instead of assuming every extra is included.
When A Repair Beats Replacing The Furnace
A diagnostic visit commonly costs $75-$200, and common repairs such as an igniter or flame sensor may run $150-$500 installed. Blower motor or control-board work can reach $400-$1,200. If the furnace is relatively young and the repair is limited, fixing it may cost less than replacement.
For an older unit with repeated failures, a major repair near $1,000 or more deserves comparison with a replacement quote. Consider the furnace’s condition, parts availability, and likely future repairs rather than relying on age alone. Get a repair estimate and replacement estimate when the proposed repair approaches a meaningful share of a new system’s price.
How To Lower A Ducted Gas Heating Estimate
Keep usable ducts when an inspection confirms they are properly sized, sealed, and in sound condition. Choose furnace capacity from a documented load calculation, and compare standard and high-efficiency equipment with the venting costs listed separately. Avoid paying for a new thermostat or accessories if existing equipment is compatible.
Get at least three itemized quotes with the same furnace capacity, AFUE range, warranty, and scope. Ask contractors to separate equipment, labor, permits, duct modifications, and disposal. Scheduling outside peak cold-weather demand may improve availability, though savings are not guaranteed. Controlling the scope and comparing equivalent quotes are more dependable savings steps than choosing equipment by sticker price alone.