HVAC COST CALCULATOR
Free tool
Quotes for the same job routinely differ by thousands. This gives you a defensible range for your home size and system type — plus the extras that get added at the end.
- Low, typical and high
- Shows the hidden extras
- Regional adjustment
Gas furnace · 1,200 sq ft · existing ducts · mid efficiency
Have a quote already? Check it against this.
What this calculator does
It gives you a defensible price range for a new heating system before you take quotes, so you can tell a fair number from an inflated one.
How the estimate is built
- Base + area — equipment scales in fixed capacity steps, not smoothly
- Efficiency tier — high-efficiency equipment runs about 30% more upfront
- Region — labour rates swing the total by 40% or more
- Access — attics and crawl spaces add roughly 15%
Sizing the system
This is a sanity check, not a substitute for a Manual J load calculation. A contractor who sizes purely on square footage is guessing, and oversized equipment short-cycles, costs more and dehumidifies poorly.
Why quotes differ by thousands
Usually equipment tier, warranty length, and whether ductwork, permits and disposal are included. A quote that is dramatically cheaper is normally builder-grade equipment, a shorter labour warranty, or work excluded now and charged later. Compare the itemised list, not the total.
Get three written quotes. This tool tells you whether they are reasonable — it does not replace them.
A quote that does not itemise these is a quote you cannot compare.
| Line item | Typical share | Your estimate | Watch for |
|---|
Ranges are US national averages for a like-for-like replacement, updated August 2026. Always get three itemised written quotes — this tool tells you whether they are reasonable, it does not replace them.
Get your estimate plus the quote comparison sheet
We'll email your range along with the sheet that makes three quotes directly comparable.
- Your low, typical and high range
- The 11 line items every quote should show
- Rebates and tax credits people forget to claim
How much does HVAC cost for a 1,200 sq ft house?
For a gas furnace replacement with existing ducts in good condition, expect roughly $4,100 to $7,850 installed, with most landing near $5,700. Adding air conditioning, replacing ductwork, or choosing high-efficiency equipment moves the top of that range considerably.
What does HVAC cost per square foot?
Between $4 and $10 per square foot for a full system in a typical home. Per-square-foot figures are a sanity check rather than a quoting method — equipment is sold in fixed capacity steps, so a 1,000 and a 1,300 sq ft home often need the same unit.
Why are my quotes so different?
Usually equipment tier, warranty length, and whether ductwork, permits and disposal are included. A quote that is thousands cheaper is normally builder-grade equipment, a shorter labour warranty, or work excluded that will be charged later. Compare the itemised list, not the total.
Is high efficiency worth the extra upfront?
It depends on your climate and fuel price. In a cold climate with long heating seasons, the payback on a high-efficiency furnace is often 6–10 years. In a mild climate it can outlast the equipment. Work out the annual saving first, then divide the price difference by it.
Should the contractor do a load calculation?
Yes. A proper Manual J load calculation sizes equipment to your actual home rather than a rule of thumb. A contractor who sizes purely on square footage is guessing, and oversized equipment short-cycles, costs more, and dehumidifies poorly.
