FurnaceInstallationCost.com

Where does the money go?

Most furnace cost guides give you a single total and call it a day. But evaluating contractor quotes requires knowing what is reasonable for each line item. Here is the full breakdown of a typical 2026 furnace install, equipment, labour, permits, removal, and ductwork.

On a $6,000 furnace install: equipment $3,300 (55%), labour $1,800 (30%), permits $200, old unit removal $300, ductwork tweaks $400. The numbers shift but the proportions stay roughly constant across the $4,000-$12,000 range.

The five line items

Share50-60%

Equipment

The furnace itself: heat exchanger, burners or heating elements, blower, gas valve, controls. Varies by fuel, brand, AFUE, capacity, and stages.

$2,000–$7,500

Share25-35%

Labour

6-14 hours of work for a 2-tech crew. Standard swap: 6-8 hours. Complex install with ductwork or fuel changes: 10-14 hours. Rates: $80-$160/hr.

$1,000–$3,000

Share2-5%

Permits

Required in nearly every US jurisdiction. Includes mechanical inspection. Higher in big cities ($300-$400), lower in rural areas ($50-$150).

$50–$400

Share2-5%

Old unit removal

Disconnect, dispose of refrigerants if AC integrated, recycle metal. Oil furnace removal is higher ($500-$1,500) because of oil tank handling.

$100–$500

Share0-15%

Ductwork mods (if needed)

Most replacements need only minor return/supply adjustments ($200-$500). Full duct replacement is uncommon and runs $2,000-$5,000.

$0–$2,500

Furnace + AC combo install

Save $500–$1,500 by replacing both at once

Furnace and central AC share the blower, ductwork, and refrigerant lines. Replacing both at once means one labour visit, one permit, and matched SEER2/AFUE for paired efficiency. Combo total: $7,000 to $15,000. The bundled saving versus doing them in separate years is real, and if your AC is over 12 years old at the time of furnace replacement, the math almost always favours doing both.

Hidden costs to watch for

Smart thermostat upgrade

$150–$500

If your existing thermostat is incompatible with a new variable-speed furnace, plan on a Nest, Ecobee, or manufacturer-specific replacement.

Gas line resize

$200–$1,500

Higher-output furnaces sometimes need a larger gas line (3/4 inch instead of 1/2 inch). Inspector will catch undersized lines.

Electrical panel upgrade

$1,200–$3,500

Rare with gas furnaces. More common with electric furnaces or heat pump conversions where 60 amps of circuit capacity is needed.

PVC venting reroute

$300–$1,200

Required when upgrading from 80% AFUE (metal flue) to 95%+ AFUE (PVC vent). Distance to exterior wall determines cost.

Condensate drain

$100–$400

95%+ AFUE condensing furnaces produce water that must drain. Pump installation is needed if the unit is below the lowest drain.

Code compliance upgrades

Varies

CO detector requirements, return air resizing, combustion air provisions. Inspector will flag during permit close-out.

What the quote should show

A reasonable furnace quote in 2026 itemises these items separately. If a contractor gives you a single lump sum without a breakdown, ask for one. Compare apples-to-apples across three quotes:

  • Brand, model number, AFUE rating, BTU capacity, stage type
  • Equipment cost line item (separate from labour)
  • Labour hours estimate and hourly rate
  • Permit cost and confirmation contractor pulls it
  • Old unit removal and disposal
  • Any ductwork, gas line, or electrical work itemised separately
  • Manufacturer warranty terms and registration responsibility
  • Labour warranty (1-2 years standard)
  • Payment schedule (no more than 25-50% deposit)

Cost breakdown FAQ

How much of furnace installation cost is labour?+
Labour is typically 25 to 35% of the total install cost, about $1,000 to $3,000 on a $5,000 to $10,000 job. A standard like-for-like swap takes 6 to 8 hours. A complex install with new gas line, ductwork modifications, or fuel conversion takes 10 to 14 hours.
Do I need a permit to install a furnace?+
Yes, in nearly every US municipality. Furnace installation is regulated under mechanical code because of gas, electrical, and combustion safety. Permits cost $50 to $400. Your contractor should pull the permit (do not let them suggest skipping it, that voids warranty coverage and home insurance).
How much does it cost to replace ductwork with a new furnace?+
Minor adjustments: $200 to $500. Significant modifications (resizing returns or supplies): $500 to $1,500. Full ductwork replacement: $2,000 to $5,000+. Most furnace replacements need only minor adjustments. Full replacement is rare and only justified when existing ducts are undersized, leaking heavily, or in poor condition.

Related cost guides

Updated 2026-04-28