HVAC Cost Methodology

General approach

Replacement and installation estimates are built bottom-up: equipment cost + labor + additional work (ductwork, permits, disposal, electrical), then multiplied by a regional factor and widened into a low-to-high range. Repair estimates use category cost bands drawn from typical installed prices, adjusted for system age and timing.

Sizing

• Cooling: about 1 ton per 500–600 square feet of conditioned space, adjusted for climate, then clamped to a 1.5–5 ton range for typical homes
• Heating: roughly 30–40 BTU per square foot for furnace sizing, clamped to 40,000–150,000 BTU/h
• A contractor should confirm sizing with a Manual J load calculation; our figure is a starting point, not a spec

Equipment cost bands (installed, per unit of capacity)

• Central AC: roughly $1,150–$1,500 per ton at standard efficiency, higher for high-efficiency and premium variable-speed equipment
• Gas furnace: roughly $22–$32 per 1,000 BTU/h installed, varying by fuel type and efficiency (AFUE)
• Air-source heat pump: roughly $1,650–$2,600 per ton depending on standard vs. cold-climate models and efficiency
• Ductless mini-split: an outdoor-unit base plus a per-zone cost for each indoor head and its line set
• Geothermal: equipment plus a ground-loop cost that scales with home size and site conditions

Labor

Labor is modeled as a base amount plus an hourly or per-capacity component, using a blended rate of roughly $80–$150 per hour. After-hours, weekend, and peak-season work carries a premium of about 1.1x to 1.6x.

Efficiency multipliers

• Standard efficiency: 1.0x on equipment
• High-efficiency: about 1.2x–1.25x
• Premium / variable-speed: about 1.45x–1.55x

Regional multipliers

• Northeast: about 1.15x
• West: about 1.12x
• Midwest: about 0.95x–0.97x
• South: about 0.90x
• National average: 1.0x

Repair cost bands

Repair calculators use typical installed price ranges by part — for example a capacitor at roughly $100–$400, a compressor at roughly $800–$2,800 — scaled for system size where relevant, and higher for R-22 systems. A diagnostic or service-call fee of roughly $75–$169 is added when selected. These are not diagnoses.

Operating and lifetime cost

Operating-cost tools estimate annual energy use from your climate's heating and cooling load, the system's efficiency (SEER2, HSPF2, AFUE, COP), and the energy prices you enter. The Heat Pump vs. Furnace + AC comparison adds a simplified electric backup-heat fraction for standard heat pumps in cold climates and projects total cost over a 10-, 15-, or 20-year horizon.

What we deliberately leave out

• Your home's actual insulation, air-sealing, and duct leakage
• Local permit and inspection fee schedules
• Individual contractor pricing, promotions, and financing
• Incentive amounts — we describe programs but do not deduct a rebate from the estimate

Limitations

These are planning estimates. Actual costs regularly fall outside the range for homes with difficult access, undersized electrical service, failed refrigerant lines, or non-standard configurations. Always get written quotes.

Data sources are listed on our Data Sources page. Our content review process is described in our Editorial Policy.

Last reviewed: August 31, 2026. Questions about this page? Contact us.