Converting a radiator-heated home to central air typically costs $8,000-$22,000 when new ductwork is needed; an average retrofit is about $14,000. The main price drivers are home size, duct access, cooling capacity, electrical work, and whether the radiator heating system stays in place or is also removed.
| Item | Low | Average | High | Notes |
|---|---|---|---|---|
| Central air with existing ducts | $4,500 | $7,500 | $12,000 | Cooling equipment and standard installation |
| Central air with new ducts | $8,000 | $14,000 | $22,000 | Typical radiator-home retrofit |
| Radiator removal | $100 each | $250 each | $500 each | Varies by size and disposal needs |
| Forced-air heat and central air conversion | $10,000 | $18,000 | $30,000 | May include furnace, ductwork, and cooling |
What central air costs in a radiator-heated home
Most radiator homes lack the supply and return ducts needed for central air. Installing a 2- to 3-ton system with new ducts usually runs $8,000-$22,000 for a 1,500- to 2,000-square-foot home, with the midpoint near $14,000. Homes with usable ductwork may pay less, while older houses with plaster walls, tight joist bays, or multiple floors can exceed the high estimate.
Central air can be added without replacing a working boiler or removing radiators. These estimates assume a standard-efficiency central AC system, typical access, and ordinary electrical conditions; local labor and equipment choices affect the quote. Assumptions: 1,500-2,000 sq ft, standard materials, normal access, no major electrical upgrade.
How equipment, ductwork, and labor shape the quote
Contractors generally separate the air conditioner, distribution system, installation work, and job-specific expenses. A site visit should confirm whether ducts can run through an attic, basement, closets, or soffits before pricing is treated as final.
| Quote component | Low | Average | High |
|---|---|---|---|
| AC condenser and indoor coil | $3,000 | $5,500 | $9,000 |
| Ducts, returns, and registers | $2,000 | $5,000 | $10,000 |
| Installation labor | $1,500 | $3,500 | $6,000 |
| Electrical work and thermostat | $300 | $900 | $2,000 |
| Permit, testing, and cleanup | $150 | $500 | $1,200 |
Duct installation and access often explain more of the price difference than the AC unit alone. Duct sealing or balancing may add $300-$1,500; extensive wall or ceiling repairs are often quoted separately.
Which home size and duct route push costs higher?
Cooling capacity and duct length need to match the home, not just its square footage. A 1,000- to 1,400-square-foot house may need roughly 1.5-2 tons, while a 2,000- to 2,500-square-foot home may need 3-4 tons. These are rough planning ranges; insulation, windows, ceiling height, and climate change the load calculation.
Long duct runs and difficult routing can add thousands even when the home is modest in size. New ducts in an accessible basement or attic may cost $2-$5 per square foot of conditioned area. Routing through finished ceilings, narrow cavities, or several floors can push the installed ductwork toward $6-$10 per square foot. A system above 3 tons may also require larger ducts, returns, or electrical service.
Which conversion choices can lower the final bill?
Keeping the boiler and radiators operational avoids the expense of replacing a separate heating system. If the goal is cooling only, request an AC-only bid rather than a combined furnace-and-AC package. Where ducts would require extensive remodeling, compare central air with ductless mini-splits; a multi-zone system often costs $8,000-$18,000, depending on the number of indoor units and installation complexity.
Compare bids with the same cooling capacity, duct scope, warranty, and electrical assumptions. A load calculation helps prevent oversizing, which can increase equipment cost and contribute to short cycling. Clearing attic or basement access before installation and scheduling outside peak summer demand may also reduce labor complications or rush charges.
How regional labor rates change radiator-home pricing
Costs vary with contractor rates, housing stock, and how much retrofit work is common locally. A straightforward installation in a lower-cost rural or Midwestern market may land 10%-15% below the national midpoint. Major Northeast and West Coast metros can run 15%-30% above it, especially where historic construction, permits, or tight access complicate duct routing.
Use regional differences as a comparison range, not a substitute for a measured quote. A $14,000 national-average project could be roughly $12,000-$13,000 in a lower-cost market or $16,000-$18,000 in a high-cost metro. Local building codes may require duct insulation, electrical updates, or inspections that shift the total.
How many installation hours should the estimate include?
An AC installation using existing ducts may take 1-2 days with a crew of 2-4 technicians. A full retrofit with new ducts commonly takes 3-7 working days, and longer if crews must open and repair finished walls or ceilings. Typical HVAC labor billing rates are about $75-$150 per technician-hour, although many contractors price the complete job rather than billing hourly.
Ask whether the bid includes duct design, startup testing, balancing, and cleanup. For example, 40-70 crew labor hours at $75-$150 per hour imply $3,000-$10,500 in labor value before differences in crew size, equipment, and packaged pricing.
What radiator and boiler removal adds to the project
Radiator removal is optional when adding central air. Taking out a typical radiator may cost $100-$300, including basic disconnection and disposal; large cast-iron units or difficult stairs can raise the charge to $300-$500 each. Removing a boiler or decommissioning hydronic heating can add about $500-$2,000, depending on piping, fuel connections, and disposal.
Do not assume radiator removal is included in an AC installation price. If the boiler stays, a heating technician should confirm the system can remain safely capped or operating as intended. If forced-air heating is planned, ask for a separate line item covering furnace installation, gas or electrical work, and any required changes to the heating controls.
Three retrofit quotes for different home layouts
A smaller 1,200-square-foot home with an accessible attic might receive a $9,500 quote: a 2-ton AC system, about 180 linear feet of ducts at roughly $4 per foot, and 35 labor hours. A 1,800-square-foot two-story home with moderate access could total $14,800, including a 3-ton system, 250 linear feet of ducts, and 55 labor hours.
Complex access can make a larger project cost substantially more than its floor area suggests. A 2,400-square-foot older home with finished ceilings might be quoted at $23,500 for a 4-ton system, 320 linear feet of ducts at about $8 per foot, 75 labor hours, and added electrical and finish work. These examples are planning estimates, not fixed regional prices; site inspection and a cooling-load calculation determine the actual scope.