Rigid duct typically costs $10-$20 per linear foot installed, while flex duct runs about $5-$10 per linear foot. For a typical 1,500- to 2,000-square-foot home, replacing accessible ductwork may cost roughly $2,000-$6,000, with layout, insulation, labor access, and local rates driving the final quote.
| Item | Low | Average | High | Notes |
|---|---|---|---|---|
| Flex duct installed | $5/linear ft | $7/linear ft | $10/linear ft | Common insulated residential runs |
| Rigid duct installed | $10/linear ft | $14/linear ft | $20/linear ft | Sheet metal, fittings, and installation |
| Whole-home replacement | $2,000 | $3,800 | $6,000+ | Accessible 1,500-2,000 sq ft home |
| Small repair or added run | $250 | $600 | $1,500 | Depends on access and connection work |
Typical prices for residential rigid and flex duct
Flex duct is usually the lower-cost choice for short, accessible branches because it installs quickly and bends around framing. Rigid sheet-metal duct costs more per foot, but can suit long trunk lines and installations where a smooth, durable interior is preferred. These ranges cover ordinary residential work, not commercial duct systems or major HVAC redesigns.
For a similar run, rigid duct commonly costs about 40%-100% more installed than flex duct. A 100-foot flex installation may land around $500-$1,000; the same length in rigid duct may run $1,000-$2,000. Those totals can rise when the job needs new plenums, many branch connections, or difficult attic or crawlspace access.
Assumptions: U.S. midrange labor, standard insulated residential duct, accessible installation, and no major framing or HVAC equipment changes.
What sheet metal, insulation, and labor add to the quote
A duct quote can combine material, installation, fittings, and removal. Ask whether the per-foot rate includes insulation, hangers, takeoffs, sealing, and disposal; two quotes can look different simply because one excludes these items.
| Quote component | Flex duct | Rigid duct | What changes the charge |
|---|---|---|---|
| Duct material | $1-$3/linear ft | $3-$7/linear ft | Diameter, insulation, and metal gauge |
| Labor | $3-$6/linear ft | $6-$12/linear ft | Cutting, fitting, supports, and access |
| Fittings and sealing | $50-$300/project | $150-$700/project | Branches, elbows, boots, and transitions |
| Removal and disposal | $100-$500/project | $150-$700/project | Old duct volume and haul distance |
| Permits or inspection | $0-$300 | $0-$300 | Local rules and scope of work |
Labor is often the largest variable, especially when rigid sections require custom measuring and multiple connections. HVAC labor commonly bills at about $75-$125 per hour, though contractors may quote a fixed project price instead.
How duct diameter, run length, and access shift the price
Duct dimensions and routing affect material use and installation time. A 6-inch branch usually costs less per foot than a 10- to 14-inch trunk line, while long routes need more supports and careful airflow sizing. A properly sized quote should identify duct diameters and approximate lengths rather than list only a lump sum.
Flex duct is sensitive to installation quality: tight bends, compression, or unsupported spans can restrict airflow. Runs longer than about 25 feet or with several sharp turns may need redesign or rigid sections to maintain performance. Rigid duct requires more fittings and labor where routes change direction, but it can be a practical choice for long straight trunks.
Attic or crawlspace work can add roughly 10%-30% when clearance is tight, temperatures are extreme, or existing lines obstruct access. Replacing damaged insulation, moving equipment, or opening and patching finished ceilings is typically quoted separately.
Flex branch runs versus rigid trunk lines
Many homes use a hybrid layout: rigid duct for the main supply trunk and flex duct for shorter branches to room registers. This can balance installation cost and routing flexibility. For example, 40 feet of rigid trunk at $12-$18 per foot plus 80 feet of flex branches at $5-$9 per foot suggests about $880-$1,440 before complex fittings, removal, or repairs.
Using flex throughout may lower the initial quote, but long or kinked runs can hurt airflow and increase heating or cooling strain. Rigid throughout can cost more and take longer to fit in crowded framing. The right comparison is a correctly sized, sealed system—not just the material price per foot.
Installation hours and crew rates for a duct replacement
A small accessible repair may take 2-5 labor hours, while a partial replacement can take 1-2 days. A whole-home replacement commonly requires a two-person crew for 1-3 days, depending on house layout, removal, and whether the system stays operational during work. These are planning ranges; a contractor should confirm timing after inspecting the routes.
Compare estimates by total installed scope and labor assumptions, not by hourly rate alone. A lower labor rate may not produce a lower bill if the estimate includes extra hours or excludes sealing and cleanup. Request the proposed duct length, number of runs, crew size, and any separate minimum service charge.
Regional labor rates and attic access across the U.S.
Prices in high-cost metro areas, including parts of the Northeast and West Coast, may run 15%-30% above the national midrange. Smaller Midwestern and Southern markets may be 5%-15% below it, although high summer demand can narrow that gap. Travel distance in rural areas can also add a service or trip charge.
Regional differences reflect wages, contractor availability, permit rules, and seasonal workload. An attic with limited clearance can cost more in any market, while an open basement with clear runs may keep labor near the lower end. Quotes should specify local taxes and permit fees where applicable.
Which quote reductions preserve airflow and duct life
Keep the job limited to damaged, leaking, or poorly sized runs when the rest of the system is sound. If the contractor recommends full replacement, ask for evidence such as crushed flex, disconnected joints, failed insulation, or leakage. A repair of one accessible branch may cost $250-$600, while replacing all ductwork is a much larger commitment.
Compare at least three written quotes using the same duct lengths, diameters, insulation levels, and removal scope. Scheduling outside peak heating or cooling demand may improve availability, though discounts vary. Avoid choosing undersized duct, skipping sealing, or accepting unsupported flex to cut the bid; poor airflow can erase the initial savings through comfort problems and added system strain.
The most reliable savings come from reducing unnecessary replacement while retaining correct sizing, insulation, support, and sealing. Ask the contractor to separate optional upgrades from required repairs and to list any warranty terms for materials and workmanship.