Updated August 15, 2026 · WattCostLab Editorial Team
Furnace Replacement Cost
A furnace replacement can range from a straightforward equipment swap to a broader HVAC project involving venting, ducts, controls and utility work.
What changes furnace replacement cost?
| Factor | Why it matters |
|---|---|
| Capacity and efficiency | Equipment selection changes upfront price and operating characteristics. |
| Venting / combustion air | High-efficiency equipment can require different venting and condensate handling. |
| Ductwork | Existing airflow problems may need repair rather than another like-for-like swap. |
| Gas and electrical work | Connections, controls or circuits can expand scope. |
| Removal / permits | Old-equipment disposal, permits and inspections should be explicit. |
Replacement is a good time to revisit sizing
Do not assume the existing furnace capacity is correct simply because it was already installed. Insulation, windows, air sealing and prior oversizing can change the appropriate design load.
Compare furnace replacement with a heat pump
If you are already replacing major HVAC equipment, compare a furnace-only path with a heat-pump or dual-fuel alternative using local electricity and fuel prices.
Related tools and guides
FAQs
Is a furnace replacement the same as a new HVAC system?
Not always. A furnace-only replacement can leave the existing air conditioner and ducts in place, while a full HVAC replacement can include both heating and cooling equipment.
Should I choose the same furnace size as the old one?
Not automatically. A current load assessment is more useful than assuming the old capacity was correct.
What should be itemized in the quote?
Equipment model, labor, venting, gas/electrical work, controls, permits, removal, startup, warranties and exclusions should be clear.
Comparing contractor proposals?
Use the free WattCostLab worksheet to compare price, warranty, included scope and exclusions.
Educational planning guide only. Verify current local prices, permits, technical requirements, incentives and contractor scope before purchase.