Ductwork Replacement Cost Calculator
Ducts are priced by the foot, so the first number to find is how many feet your house has. The average cost to replace ductwork across a whole house is about $3,000 to $7,500, so the length of the system and the material decide where in that range your ductwork replacement cost falls.
How much ductwork is in a house?
An average 2,500 sq ft home has about 275 linear feet of ducts. Homes of 1,800 to 3,500 sq ft typically have 190 to 350 feet, for example 255 feet in an 1,800 sq ft house and 315 feet at 2,750 sq ft. The calculator starts at 250 feet.
Ductwork replacement cost by length
| Duct length | Installed cost |
|---|---|
| 100 ft | $1,600 to $1,900 |
| 200 ft | $3,100 to $3,700 |
| 300 ft | $4,700 to $5,600 |
| 400 ft | $6,200 to $7,500 |
| 500 ft | $7,800 to $9,300 |
That works out to roughly $16 to $19 per foot, a common general rate.
Sheet metal or flex duct
Installed sheet metal runs $10 to $30 per foot, including sealing and hangers, and flex duct $4 to $12. Material alone is $7 to $15 a foot for sheet metal and $1 to $4 for flexible duct, insulated or not.
Some price lists quote about twice these per-foot rates for galvanized steel, up to $62 a foot, yet put the cost of new ductwork in an average home at $3,000 to $6,000, in line with everything else. We have not used the higher per-foot figures.
These rates assume open framing; in a finished home the same job can cost two to four times as much.
Replace all of it, or just a run?
Not every duct problem calls for new ductwork throughout. A partial replacement of one floor or the attic costs $800 to $6,000, with $2,200 typical. For a single damaged section, expect $250 to $3,000; the average air duct repair cost is about $600.
Full replacement is a bigger commitment. For a 1,500 to 2,000 sq ft home, whole-house quotes run from $3,000 to $15,000, with $7,500 typical.
What else goes on the quote
| Line | Typical cost |
|---|---|
| Removing old ducts | $100 to $800 |
| Sealing the system | $1,000 to $3,000 |
| Insulating ducts | $1,000 to $2,500 |
| Hard attic or crawl space access | $200 to $2,000 |
| Permit | $50 to $400 |
| Asbestos or mold found in old ducts | $300 to $3,000 |
Cleaning is a different job altogether: air duct cleaning costs $300 to $700 for a 2,000 sq ft home.
Is it really the ducts?
ENERGY STAR says about 20 to 30 percent of the air moving through a typical duct system is lost to leaks, holes and poor connections. Its warning signs are high summer and winter bills, rooms that are hard to heat or cool, stuffy rooms and kinked flex ducts. Widespread corrosion or physical damage is another.
Age alone is a weak reason. Flex ducts last 10 to 20 years and metal ducts 20 years or more, but old ducts in good shape do not need replacing just because of their age. Sealing, at $1,000 to $3,000, costs less than the air duct replacement cost for a whole system.
Ductwork cost per linear foot by duct type
| Duct type | Low | High |
|---|---|---|
| Flexible duct | $4.00 | $12.00 |
| Sheet metal | $10.00 | $30.00 |