Introduction
Ductwork is one of the least visible line items in an HVAC project and one of the most variable in price: the same 2,000 sq ft home can see ductwork quotes thousands of dollars apart depending on material, access, and region. Understanding what drives the cost — linear footage, fitting count, material choice, and labor conditions — lets you read a quote intelligently instead of just comparing bottom lines. The Ductwork Calculator helps with the first half of any estimate by sizing every run and trunk, which is the basis for counting materials; this guide covers the second half — what those materials and the labor to install them typically cost in the US.
All figures below are typical US planning ranges for 2026, not quotes. Labor rates vary sharply by metro area, and material prices move with steel markets — treat every number here as a budgeting bracket, then confirm with local contractors.
What Drives Ductwork Cost
Five factors explain most of the spread between a $3,000 job and a $9,000 job:
- Material type. Flexible duct is cheapest to buy and fastest to install; fabricated sheet metal costs more in both material and labor; duct board sits between. The trade-offs are covered in the material guide.
- Total linear footage and fitting count. Every takeoff, elbow, transition, and boot is material plus labor. A compact single-trunk layout costs far less than a sprawling multi-trunk one serving the same rooms.
- Access conditions. Open basement or new construction: fast and cheap. Finished attic with blown insulation, tight crawlspace, or cutting open drywall: slow and expensive.
- System scope. Adding two branch runs is a half-day job; a full whole-house replacement with new trunk, returns, and sealing is a multi-day project.
- Region and labor market. Installed prices in high-cost coastal metros can run 30–50% above the same job in lower-cost markets. Always get at least three local quotes.
Typical Cost Ranges
Per linear foot, installed
| Scope | Typical installed range (US) | Metric equivalent |
|---|---|---|
| Flexible duct run (insulated, R-6/R-8) | $15–$30 per linear ft | $49–$98 per meter |
| Sheet metal trunk / branch | $25–$55 per linear ft | $82–$180 per meter |
| Duct board trunk | $20–$40 per linear ft | $66–$131 per meter |
Per supply run, installed
A “run” means one complete branch: takeoff with damper, duct, elbows, boot, and register. Typical installed cost per run:
| Run type | Typical installed range |
|---|---|
| Flex run, easy attic/basement access | $150–$300 |
| Flex run, difficult access | $250–$450 |
| Sheet metal run | $300–$600 |
Whole-house systems
Full duct replacement for a typical single-family home (1,500–2,500 sq ft / 140–230 m², 8–14 supply runs plus returns):
- Flex-duct system: $3,000–$6,000 installed
- Sheet metal trunk + flex branches (hybrid): $4,500–$8,000 installed
- Full sheet metal system: $6,000–$12,000+ installed
- Duct sealing only (existing ducts): $1,000–$3,500 depending on method and access
New-construction ductwork typically lands 15–25% below replacement cost for the same house because access is open and no demolition or patching is needed.
Material-Only Costs
For DIY budgeting or checking a contractor’s material allowance:
| Material | Typical material cost |
|---|---|
| Insulated flex duct, 25-ft box | $40–$90 ($1.60–$3.60/ft) |
| Round sheet metal pipe, per 5-ft section | $15–$40 depending on diameter |
| Fabricated rectangular trunk, per linear ft | $8–$20 |
| Takeoff with damper | $8–$20 each |
| 90° elbow (round metal) | $8–$18 each |
| Register boot + grille | $15–$40 each |
| Duct mastic, 1-gallon | $15–$30 |
Rule of thumb: on a professionally installed job, labor typically represents 50–65% of the total — materials are the smaller half. A quote that’s dramatically below these ranges usually means corners on sealing, supports, or balancing dampers. The estimating guide walks through counting every fitting so a material list is complete before pricing.
Cost Factors Worth Paying For
Not every upcharge is worth it, but these usually are:
- Proper sealing (mastic, not just tape). Leaky ducts waste 20–30% of conditioned air in typical older systems. Sealing is the highest-ROI ductwork spending there is.
- R-8 insulation in unconditioned spaces. Required by energy code in many jurisdictions now; the incremental cost over R-6 is small.
- Balancing dampers at every takeoff. A few dollars per run at install time; enormously expensive to retrofit.
- Correct sizing per Manual D. An undersized trunk starves distant rooms forever. Paying for proper design — or verifying a proposal with the complete sizing guide — costs nothing next to living with the mistake.
Ways to Keep Costs Down
- Keep the layout compact. Every extra foot of trunk and every extra fitting costs money twice (material + labor). A central trunk with short branches beats a perimeter loop.
- Bundle with equipment replacement. Doing ducts when the furnace/air handler is already being replaced saves on access labor and coordination.
- Choose hybrid construction. Sheet metal trunk for the long, high-airflow mains plus flex branches is the sweet spot of performance and price for most homes.
- Handle the easy parts yourself — but know the boundary. Sealing accessible ducts with mastic is very DIY-friendly; full system design and sheet metal fabrication are not. See DIY vs pro for where the line sits.
- Get itemized quotes. Ask for material vs. labor and per-run pricing, not just a lump sum — it makes competing bids comparable and exposes padded line items.
Sample Budget: 10-Run Retrofit
A planning sketch for a 1,800 sq ft (167 m²) single-story home, hybrid system, moderate access:
| Item | Qty | Planning figure |
|---|---|---|
| Sheet metal trunk, ~40 ft (12 m) | 1 | $1,000–$2,200 |
| Flex branch runs with boots/grilles | 10 | $1,500–$3,000 |
| Return trunk + 2 return grilles | 1 | $600–$1,200 |
| Takeoffs with dampers | 10 | $150–$300 (materials) |
| Sealing (mastic, all joints) | — | $300–$700 |
| Planning total | $3,550–$7,400 |
Before committing to a retrofit budget, check what your jurisdiction requires — insulation levels, sealing standards, and permits all affect the final number, as detailed in the code compliance guide.
Related Guides
- Complete Guide — how duct sizes are calculated, with a worked example.
- Estimating Guide — counting fittings and building a material list.
- Material Guide — sheet metal vs flex vs duct board compared.
- DIY vs Pro — which ductwork tasks are worth doing yourself.
- FAQ — quick answers on sizing and costs.
Frequently Asked Questions
How much does it cost to replace ductwork in a 2,000 sq ft house?
Typical US planning range: $4,000–$9,000 installed for a full replacement, depending on material (flex vs sheet metal), access difficulty, and region. High-cost metros can exceed this; get three local quotes.
What does ductwork cost per linear foot?
Installed: roughly $15–$30/ft ($49–$98/m) for insulated flex runs, $25–$55/ft ($82–$180/m) for sheet metal. Material-only is roughly half those figures.
Is it cheaper to repair or replace ductwork?
Sealing and repairing accessible ducts ($1,000–$3,500) beats replacement when the layout is sound and ducts are intact. Replace when ducts are crushed, undersized, mold-contaminated, or over 20–25 years old.
Does new ductwork improve efficiency?
Properly sized and sealed new ductwork can cut duct losses from 20–30% to under 5–10%, which often shows up directly in energy bills — especially when the old ducts ran through a hot attic.
Why do ductwork quotes vary so much?
Material choice, fitting count, access difficulty, scope (runs vs full system), and local labor rates each swing the total by thousands. Itemized per-run quotes are the only way to compare bids fairly.
Get Your Number
Every ductwork budget starts with quantities: how many feet of trunk, how many branch runs, how many takeoffs, elbows, and boots. Size the system first with the Ductwork Calculator, count the fittings from that layout, apply the ranges above with a regional adjustment — and then get itemized local quotes to replace every planning figure with a real one.
Disclaimer: All cost figures are typical US planning ranges for budgeting purposes only and vary significantly by region, access conditions, and material prices. They are not quotes. Verify requirements with your local building authority and consult a licensed HVAC professional before committing to a project.
