How Much Does It Cost to Install New Ductwork? A Complete 2026 Pricing Guide

Installing new ductwork costs $3,000 to $7,000 for a typical 2,000-square-foot single-family home in 2026, with the national average around $4,500. The price per linear foot of duct runs $12 to $25 for supply ducts and $15 to $30 for return ducts, including materials, labor, fittings, hangers, and insulation. The total cost depends on four variables: whether the installation is new construction (open walls) or retrofit (finished walls), what material the ducts are made of, how many linear feet of duct the house requires, and how accessible the installation path is.

A new construction duct installation in a house with open stud walls and an unfinished basement costs $1.50 to $3.00 per square foot of living space. The same duct system installed as a retrofit in a finished house — where the installer must work through existing wall cavities, cut access holes in drywall, and navigate around plumbing and electrical — costs $3.00 to $6.00 per square foot. The labor difference between new construction and retrofit is roughly double, because the installer spends as much time figuring out how to route each duct as they spend actually installing it.

Ductwork Installation Cost by Home Size

The duct length estimates assume a central HVAC system with a single furnace or air handler in the basement or a mechanical room. Houses with the HVAC equipment in an attic or a crawlspace typically have shorter duct runs because the equipment is closer to the rooms. Houses with the equipment in a basement and bedrooms on the second floor have longer duct runs because the ducts must travel vertically through walls and horizontally across ceilings. Two-story houses cost 20% to 40% more to duct than single-story houses of the same square footage.

Ductwork Material Costs: Flex vs. Rigid vs. Fiberboard

Flexible duct (a wire-reinforced plastic tube with fiberglass insulation) is the most common material for residential retrofit installations because it can be snaked through wall cavities, around corners, and across attics without requiring fabricated metal fittings at every turn.

The trade-off is airflow: flex duct has roughly 3 to 5 times more airflow resistance per foot than smooth metal duct because the interior surface is ribbed, not smooth. An HVAC system designed for metal duct that is installed with flex duct will deliver less airflow to the registers.

A system designed for flex duct will work fine, but the duct runs must be shorter and the ducts must be pulled tight. Sagging flex duct creates a U-bend that doubles the airflow resistance of that section.

Galvanized steel duct is the premium material. It is rigid, smooth on the inside (minimal airflow resistance), and lasts the life of the house. But it must be fabricated to fit the specific dimensions of each duct run, which requires a sheet metal shop or a contractor with an on-site fabrication trailer.

Rectangular galvanized duct is standard for main trunk lines in basements. Round spiral duct is used for exposed ductwork in finished basements, restaurants, and commercial spaces where the duct is a visible design element.

The cost premium for spiral duct over rectangular galvanized is $3 to $10 per linear foot, and that premium buys a product that looks like it was meant to be seen.

What Else Is Included in a Ductwork Installation

A ductwork installation quote that covers only the linear feet of duct is not a complete quote. The duct is the largest line item, but the fittings, the registers, the insulation, and the labor to connect everything add up to 40% to 60% of the total cost.

• Fittings: Elbows, wyes, reducers, takeoffs, and end caps connect the ducts to each other and to the main trunk line. Fittings cost $10 to $50 each, and a typical installation uses 15 to 30 fittings. Fabricated metal fittings cost more than pre-made flex duct fittings.
• Registers and grilles: Each supply register costs $10 to $30. Each return grille costs $15 to $50. A 15-vent house has roughly $200 to $500 in register and grille costs. The visible registers in the living space are the only part of the duct system the homeowner ever sees, and cheap plastic registers look exactly like what they cost.
• Volume dampers: Manual dampers inside the branch ducts allow the installer to balance airflow between rooms. Each damper costs $10 to $20, and one is installed in every branch duct. Motorized dampers for zoned systems cost $80 to $150 each and require wiring back to the zone control panel.
• Duct insulation: Ducts in unconditioned spaces — attics, crawlspaces, garages — must be insulated to prevent condensation in summer and heat loss in winter. Wrap insulation costs $2 to $4 per linear foot. Flex duct has insulation built in. Metal duct requires a separate insulation wrap.
• Duct sealing: Every seam and joint in a metal duct system must be sealed with mastic or aluminum tape to prevent air leakage. An unsealed duct system leaks 20% to 30% of its conditioned air into the attic, the basement, or the wall cavities. Mastic sealing adds $1 to $2 per linear foot and is not optional.
• Permits: A mechanical permit for ductwork installation costs $100 to $300 depending on the municipality. The permit ensures the installation is inspected for compliance with the International Mechanical Code.

The most important line item: Duct sealing with mastic — a thick, brush-on paste that hardens to a flexible seal — is the difference between a duct system that delivers the BTUs you paid for and one that air-conditions the attic. An unsealed duct system loses 20% to 30% of its conditioned air through leaks. Metal tape (not cloth “duct tape,” which is not for ducts) is acceptable for some seams, but mastic is the standard for a permanent seal. Verify that the quote includes mastic sealing of all accessible seams and joints.

When to Replace Ductwork vs. Repair It

Ductwork does not have a fixed replacement interval like a roof or a water heater. It is replaced when it is damaged, undersized, leaky beyond repair, or made of a material that has deteriorated. The decision to replace rather than repair is driven by the condition of the existing ducts, not by their age.

The most common duct replacement scenario is the installation of a new high-efficiency HVAC system on existing ductwork that was sized for the original equipment 30 years ago. New systems move more air at lower static pressure, and ducts that were marginally adequate for a 1980s furnace are undersized for a modern variable-speed system. Replacing the equipment without addressing the ductwork is like putting a new engine in a car with a clogged exhaust. The engine can produce the power. The ductwork cannot deliver it to the rooms.

Regional Ductwork Installation Costs

FAQ: Common Questions About Ductwork Installation

Is flex duct as good as metal duct?

Flex duct is not as good as metal duct for airflow — it has higher friction loss per foot — but it is adequate if the duct runs are kept short (under 15 feet), pulled tight (no sags or kinks), and the HVAC system is designed with flex duct’s higher resistance in mind. A metal duct system retrofitted with flex duct without adjusting the blower speed or the duct sizing will underperform. A flex duct system designed from the start with Manual D calculations will deliver the specified airflow. The problem is not flex duct. The problem is flex duct installed by an installer who treats it like a Slinky and pulls it around corners with no regard for airflow.

Do I need ductwork for a mini-split system?

No. Ductless mini-split systems do not use ductwork. Each indoor unit is mounted on the wall or ceiling in the room it serves, and refrigerant lines — not air ducts — connect the indoor units to the outdoor condenser. A ductless system eliminates the cost of installing new ductwork entirely, which is one of the primary reasons mini-splits are the preferred HVAC solution for older homes that never had central air conditioning. The trade-off is that each room or zone needs its own indoor unit, and the indoor units are visible on the wall.

New Ductwork Is a System Investment, Not a Commodity Purchase

A $4,500 ductwork installation is not $4,500 worth of metal tubes. It is $1,500 to $2,000 in materials — the ducts, the fittings, the registers, the dampers, the insulation, the mastic — and $2,500 to $3,000 in skilled labor to fabricate, route, hang, seal, and balance the system. The labor cost is the value: an installer who routes ducts to minimize bends, sizes each branch correctly, pulls flex duct tight, and mastic-seals every seam produces a system that delivers the BTUs the equipment produces. An installer who takes shortcuts produces a system that delivers 70% of those BTUs to the attic.

When comparing quotes, look for a Manual D load calculation — the ACCA standard for residential duct design. A contractor who cannot produce one is guessing at the duct sizes. A contractor who does produce one sized every branch duct to deliver a specific CFM of airflow to each room within the system’s available static pressure. The Manual D is the difference between a duct system that works and one that leaves the farthest bedroom cold in January and hot in July.