Estimated HVAC replacement cost: $8,500, ranging from $6,700 to $11,100.
Estimated HVAC replacement cost
low confidence
$8,500Installed, before contingency
$6,700 lowhigh $11,100
What makes up the typical figure
Gas furnace + air conditioner — equipment$6,200
Installation labor$1,600
Remove and dispose of old system$400
Everything else$300
United States average
+15% contingency advised
Assumptions 2026.07.1
Why low: no state was resolved, so national averages were used; the modeled range spans about 52% of the typical value.
Quick facts
System size
3.5 tonsSized from 2,000 sq ft in IECC zone 4. A contractor should confirm with a Manual J load calculation.
Cooling capacity
42,000 BTU/hr
Cost per ton installed
$2,429($1,904 – $3,174)
Climate zone
4Unweighted mean of state degree days (2021–2025 mean); no state resolved.
Cost breakdown
Estimated cost of each component, with low, typical, and high values.
Component
Low
Typical
High
Gas furnace + air conditioner — equipmentEquipment3.5 tons at mid efficiency, mainstream brand.
$4,500
$6,200
$8,500
Installation laborLabor22 technician-hours at $73/hr billed.
$1,000
$1,600
$2,550
Remove and dispose of old systemRemovalIncludes refrigerant recovery, which is legally required.
$200
$400
$800
Permit and inspectionPermit
$100
$300
$750
Estimated HVAC replacement cost
$6,700
$8,500
$11,100
Recommended contingency (15%)HVAC contingency covers what the installer finds behind the old unit: undersized returns, a condensate path that does not drain, a flue that no longer meets code, or a panel with no room for the new circuit.
$1,000
$1,300
$1,650
Total to budget
$7,700
$9,800
$12,750
The low and high columns above will not add up to the headline range. Each line has its own uncertainty, and every line landing at its worst case at the same time is unlikely, so the total combines them as partially independent rather than summing the extremes.
How this number was produced+
Sizing2,000 sq ft / 550 sq ft per ton (zone 4)3.5 tons
Equipment$1450/ton x 3.5 tons x 1.22 efficiency x 1 brand$6,191
Labor22 hr x $73/hr$1,610
Totalcomponents combined as partially independent uncertainties$8,501
Adjustments applied
Climate-based sizing×1.17
Unweighted mean of state degree days (2021–2025 mean); no state resolved. At 550 sq ft per ton for zone 4, 2,000 sq ft sizes to 3.5 tons.
Efficiency tier — Mid efficiency×1.22
Higher efficiency raises equipment cost and lowers running cost. Whether it pays back depends on your electricity price and how long the cooling season is.
Regional labor — national×1.00
National 49-9021 Heating, Air Conditioning, and Refrigeration Mechanics and Installers mean wage of $31.14/hr (BLS OEWS May 2025), times the contractor burden multiplier.
Installation access×1.00
Easy — garage, basement, or ground-level closet
Notes and sources3 notes, 3 sources
Worth knowing
Square-foot sizing is a shortcut. A proper Manual J load calculation accounts for insulation, window area and orientation, air leakage, and ceiling height, and it routinely lands a half-ton to a full ton away from the rule of thumb.
Oversizing is a real problem, not a safety margin: an oversized system short cycles, never runs long enough to pull humidity out of the air, and wears itself out faster.
Utility rebates and federal tax credits for high-efficiency equipment can be substantial and are not included in these figures.
Sources
U.S. Bureau of Labor Statistics, Occupational Employment and Wage Statistics (OEWS), State cross-industry estimatesprimaryMay 2025retrieved 2026-07-31
PlainTotal editorial baseline, reviewed against publicly advertised supplier pricing, manufacturer specifications, and published trade guidanceassumption2026 national baselineretrieved 2026-07-31
NOAA Climate Prediction Center, population-weighted daily degree days (StatesCONUS), 5-year mean. Alaska and Hawaii from U.S. Energy Information Administration State Energy Data System indicators.mixed2021–2025 meanretrieved 2026-07-31
It is system type, efficiency tier, whether the ductwork is being replaced, and how hard the equipment is to reach. This calculator sizes a system from your square footage and local climate, then prices each of those pieces separately so you can see which one is driving the number.
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Methodology
How this calculator works
How the system is sized
Cooling capacity is measured in tons, where one ton is 12,000 BTU per hour. We divide your conditioned floor area by a square-feet-per-ton figure that varies with your climate zone: about 430 sq ft per ton on the Gulf Coast, about 680 further north, because a hot-humid climate needs more capacity for the same house.
Your climate zone is derived from population-weighted cooling and heating degree days published by NOAA, averaged over five years so a single hot summer does not skew it.
This is a shortcut and we want to be plain about that. The real method is a Manual J load calculation, which accounts for insulation levels, window area and orientation, infiltration, and ceiling height. It commonly disagrees with the rule of thumb by half a ton or more. Any contractor who sizes your system by square footage alone is guessing too.
How equipment and labor are priced
Equipment is priced per ton for the system type you selected, then multiplied by an efficiency premium and a brand tier. A premium variable-speed system runs close to twice the cost of builder-grade equipment of the same capacity.
Labor uses the Bureau of Labor Statistics mean hourly wage for HVAC mechanics and installers in your state, multiplied by a contractor burden factor covering insurance, overhead, vehicles, and profit. Installation hours come from the system type, adjusted for how hard the equipment is to reach.
What is not included
Utility rebates, manufacturer promotions, and federal efficiency tax credits are excluded. For high-efficiency heat pumps these can be worth thousands of dollars and materially change the comparison between tiers.
Nor is running cost. A premium system costs more to buy and less to operate; which one wins over ten years depends on your electricity price and climate. Our air conditioner running cost calculator covers the operating side.
Location and data
Where the numbers come from
Location is optional, and we only ask for a ZIP code or a state — never a street address. A ZIP code is matched to its state using published postal prefix ranges, and that state is used to look up labor and price rows in the tables below. If you leave it blank, or your ZIP cannot be matched, the estimate falls back to a national average and says so on the result.
Nothing you enter is transmitted or stored. The calculation runs entirely in your browser, and the only place your inputs appear is in the page URL, so you can bookmark or share a result if you choose to.
primaryMay 2025v2025.05
U.S. Bureau of Labor Statistics, Occupational Employment and Wage Statistics (OEWS), State cross-industry estimates
Hourly mean wage (H_MEAN) for each trade. These are employee wages, not billed contractor rates. Billed rates are derived in the engine by applying a documented burden-and-overhead multiplier; see docs/calculator-methodology.md.
mixed2021–2025 meanv2026.07
NOAA Climate Prediction Center, population-weighted daily degree days (StatesCONUS), 5-year mean. Alaska and Hawaii from U.S. Energy Information Administration State Energy Data System indicators.
Degree days are population-weighted state means over a 5-year window, which smooths single-year weather swings. IECC zone is DERIVED from HDD65 threshold bands and is the dominant zone for the state only; IECC assigns zones by county and large states span several. Alaska and Hawaii are not in the NOAA CONUS product and use EIA SEDS values. The District of Columbia inherits Maryland.
assumption2026 national baselinev2026.07.1
PlainTotal editorial baseline, reviewed against publicly advertised supplier pricing, manufacturer specifications, and published trade guidance
These are NOT published statistics. No public agency publishes a national residential material price index at this granularity, and proprietary construction cost databases cannot be reproduced. Each figure is a documented editorial baseline for material only, excluding labor, delivered to a metropolitan supply yard, before regional adjustment and before sales tax. They are the least certain inputs in the project calculators and are the first thing to replace with surveyed data. Labor hours are crew-hours for a competent crew under normal conditions.
These are the figures we chose rather than measured. For each one we record the range of values found across references, what we selected, and why — because an estimate you cannot interrogate is not much better than a guess. The 2 marked high risk are the ones most likely to be wrong and most consequential when they are.
Published contractor pricing guidance and trade-association break-even material put the wage-to-billed-rate multiplier between roughly 1.8x for an owner-operator with minimal overhead and 3.0x for an insured company with vehicles, office staff, and target profit. We narrowed the shipped band to 2.0-2.75 because the extremes describe business models a homeowner rarely encounters: below 2.0 usually means an uninsured single operator, above 2.75 usually means commercial or specialty work. Roofing sits at the top of the band because workers' compensation for roofers is several times the rate of other trades.
Applies to
United States, all states. The multiplier itself is not regionally adjusted — regional variation enters through the underlying BLS wage, not through the burden.
Known limits
The single largest lever in every project calculator. A 10% error here moves every project estimate by roughly 6%.
Sources
Recorded before the richer schema; see rationale for provenance
Last verified
2026-07-31 · reviewed annual
Square feet served per ton of cooling, by climate zonehigh risklow confidence+
Observed range
350 — 900 (typical 550)square feet per ton
Why this value
Rules of thumb span 350 sq ft per ton for older leaky housing in hot climates to 900 for new tight construction in mild ones. We selected a zone-graded ladder centred on 550 for zone 4. This is explicitly a shortcut: a Manual J load calculation accounts for insulation, glazing, orientation, and infiltration, and routinely disagrees by half a ton or more. The page says so.
Applies to
United States, by IECC climate zone.
Known limits
Sizing drives equipment cost almost linearly, so a half-ton error moves the estimate by roughly 15%.
Sources
Recorded before the richer schema; see rationale for provenance
Last verified
2026-07-31 · reviewed biennial
Recommended contingency by job charactermedium confidence+
Observed range
0.05 — 0.25 (typical 0.15)share of project cost
Why this value
Published renovation guidance clusters at 10% for like-for-like replacement, 15% where hidden damage is common, and 20% for work crossing several trades. Values below 10% assume a job where nothing is opened up; values above 25% are usually quoted for historic or structurally compromised properties, which is outside what these calculators model.
Applies to
United States. Older housing stock warrants the upper figure regardless of region.
Known limits
No additional limitation recorded.
Sources
Recorded before the richer schema; see rationale for provenance
Last verified
2026-07-31 · reviewed annual
Regional material price sensitivitymedium confidence+
Observed range
0 — 0.5 (typical 0.25)share of the local labor differential
Why this value
Building materials are nationally traded commodities, so the floor case is 0.0 — no regional variation at all beyond freight. The ceiling case of 0.5 would imply materials track local wages half as strongly as labor does, which overstates it: what actually varies locally is freight, yard margin, distribution labor, and sales tax, not the commodity. We selected 0.25 as a single point rather than a band because modelling it as uncertain would double-count uncertainty already carried by the material price band itself.
Applies to
Continental United States. Alaska and Hawaii almost certainly warrant a higher figure because of shipping, and are not currently distinguished.
Known limits
No additional limitation recorded.
Sources
Recorded before the richer schema; see rationale for provenance
Last verified
2026-07-31 · reviewed annual
HVAC permit and inspection feemedium confidence+
Observed range
0 — 1200 (typical 300)USD
Why this value
Mechanical permits are more consistently required than roofing permits and more consistently flat-fee. The band reflects small-town flat fees at the bottom and metropolitan mechanical-plus-electrical combinations at the top.
Applies to
United States, highly local.
Known limits
No additional limitation recorded.
Sources
Recorded before the richer schema; see rationale for provenance
Last verified
2026-07-31 · reviewed annual
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Cost factors
What changes the price most
System type
Reusing an existing furnace and replacing only the air conditioner is the cheapest path. A ground-source heat pump can cost five times as much because of the loop field.
Ductwork
Often the difference between two wildly different quotes. Full replacement can rival the equipment cost.
Efficiency tier
Roughly a 2x spread between federal-minimum and premium variable-speed equipment of the same capacity.
Sizing
Capacity drives equipment cost almost linearly. Oversizing wastes money twice — once at purchase, and again in comfort and equipment life.
Access
A tight attic in August adds hours and makes future service more expensive too.
Electrical capacity
Heat pumps and larger air handlers sometimes need a service upgrade, which is a separate trade and a separate permit.
Questions
Frequently asked
How much does it cost to replace an HVAC system?
+
For a typical 2,000 square foot home, a mid-efficiency furnace and air conditioner with sound existing ductwork usually lands in the high four figures to mid five figures installed. Replacing ductwork, choosing premium efficiency, or moving to a ground-source system can multiply that. Enter your details above for a state-adjusted figure.
What size HVAC system do I need?
+
As a starting point, one ton per 430 to 680 square feet depending on your climate. This calculator applies the right figure for your zone automatically. Insist on a Manual J load calculation before signing anything — square footage alone misses insulation, windows, and air leakage, which are exactly the things that determine the real load.
Is a high-efficiency system worth the extra cost?
+
It depends on your electricity price and how many hours a year the system runs. In a hot climate with expensive power, the payback can be reasonable. In a mild climate with cheap power, the premium often outlives the equipment. The stronger arguments for premium equipment are usually comfort and humidity control rather than the energy bill.
Should I replace the furnace and air conditioner at the same time?
+
If both are near end of life, usually yes. They share the indoor coil and blower, and matched equipment is rated as a system. Replacing one and reusing an old blower can leave you paying twice for labor and not getting the efficiency you paid for.
How long should an HVAC system last?
+
Fifteen to twenty years is typical for a furnace and twelve to eighteen for an air conditioner or heat pump, with wide variation for maintenance, climate, and whether the system was correctly sized. An oversized system that short cycles will not reach the top of that range.