Furnace Replacement Cost Calculator
Swap a central furnace using tonnage/BTU band, AFUE tier, gas vs propane, and whether ducts need rework.
Your project
Units
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Units
Leave at 1 for a single furnace; use 2 only if you truly have separate systems. |
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Capacity
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Capacity
Match output to climate and home size — load calculations beat rules of thumb. |
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Efficiency tier
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AFUE
Standard 80% AFUE vs high-efficiency 95%+ condensing units. |
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Fuel
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Fuel
Propane and oil setups may need tank or line work outside this model. |
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Duct modifications
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Ducts
Plenum changes or adding returns show up as labor in these tiers. |
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Your state
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Your state
Scales midpoints for typical state-level labor and material costs versus the U.S. average. Not a local contractor bid. |
How to use this calculator
- Confirm one or two furnace systems.
- Select capacity, efficiency, fuel, and duct scope.
- Pick your state.
Results explained
Flat duct fees apply once per job; equipment scales per system count. AC coil pairing is not included.
Quick reference: furnace replacement
| System | Midpoint |
|---|---|
| 80% AFUE, 100k gas | $3,850 |
| 95%+ condensing | $5,450 |
| Major duct rework | +$2,850 |
How the estimate is built
(Efficiency base + capacity add-on) × units plus duct flat fees; propane fuel type is informational in copy — adjust quotes locally.
Example scenario
One 100k 95% furnace with minor duct tweaks ≈ $6,400 at U.S. average.
FAQ
Heat pump instead?
Dual-fuel or heat-pump systems differ — this tool is furnace-only.
Permits & inspection?
Often bundled in install quotes; not broken out here.
Warranty labor?
Extended labor warranties are optional upsells from contractors.