Ductwork Replacement Cost (2026): DIY vs Hiring a Pro
Updated
Verdict Do it yourself · Whole house, flex ducts in the attic
Replacing ductwork costs $1,120–$1,518 to do yourself and $3,000–$7,000 to hire a pro, per 1,500 sq ft house (about 200 ft of duct, 10 registers).
Replace flex ductwork yourself if it's a like-for-like job in an attic or crawl space you can work in: materials and tools for a 1,500 sq ft house come to $1,120–$1,518 against a $4,500 quote — a saving of about $3,200, or roughly $170 for every hour of hot, dusty work — and a few damaged runs are a $290 saving for an afternoon. Hire an HVAC contractor for a sheet metal trunk system, for any job that changes duct sizes, adds returns or moves registers, for ducts buried in finished walls, and wherever the code requires a licensed installer.
- DIY A few damaged runs
- DIY Whole house, flex ducts in the attic
- DIY Whole house, ducts in a crawl space
- Hire Two-story, sheet metal trunk and branches
- DIY cost
- $1,120–$1,518
- 14–24 hours of your time · whole house, flex ducts in the attic
- Pro cost
- $3,000–$7,000
- typical $4,500 · per 1,500 sq ft house (about 200 ft of duct, 10 registers)
- Typical savings
- $3,181
- 71% less than a pro · ≈ $167/hour for your time
- Pros charge $10–$25 per linear foot for insulated flex and $25–$55 for sheet metal, removal included: about $750 for a few damaged runs, $4,500 for a 1,500 sq ft house with attic flex, $5,500 on a crawl space, $10,000 for a two-story sheet metal system.
- Ductwork is mostly labor. Materials for a whole-house flex replacement are $1,120–$1,518 including tools, against a $4,500 quote — a $3,200 saving, or about $170 an hour for 14–24 hours in an attic.
- That saving is real only for like-for-like flex replacement. Resizing runs, adding returns, a sheet metal trunk, or ducts in finished walls are design and fabrication work — hire those.
- The system is only as good as the sealing and support: mastic on every joint, straps every 4 ft, runs pulled tight. ENERGY STAR puts leakage in typical duct systems at 20–30% of the air moved.
DIY vs pro at a glance
| DIY | Pro | |
|---|---|---|
| Cost per job (whole house, flex ducts in the attic) | $1,120–$1,518 | $3,000–$7,000 |
| Cost range (all sizes) | $327–$6,762 | $450–$15,000 |
| Your time | 14–24 hours | Getting quotes, ~1–2 hours |
| Skill needed | Intermediate | None |
| Injury / damage risk | Medium | Carried by the contractor (if insured) |
| Equipment you'd need to buy or rent | Duct strap tensioning tool, Aviation tin snips, Respirator, gloves, coveralls, headlamp, knee pads | None |
| Permit | Sometimes — you apply | Sometimes — usually pulled by the pro |
| Best when | The ducts are flex, in an attic or crawl space you can move through, and you're replacing them size-for-size on the same layout | The system is sheet metal, or you want to upgrade to it — trunk fabrication and fitting is a trade |
What pros charge for replacing ductwork
| Job size | Low | Typical | High |
|---|---|---|---|
| A few damaged runs — three crushed, torn or rodent-damaged flex branch runs in an attic, about 60 ft of 6–8 in insulated flex | $450 | $750 | $1,200 |
| Whole house, flex ducts in the attic — 1,500 sq ft single-story: about 200 ft of R-8 flex, 10 supply runs and boots, one or two returns; plenum reused or replaced | $3,000 | $4,500 | $7,000 |
| Whole house, ducts in a crawl space — 1,500 sq ft on a crawl space: same duct count, but working on your back in 24 in of clearance | $3,500 | $5,500 | $8,000 |
| Two-story, sheet metal trunk and branches — 2,000 sq ft: fabricated rectangular trunk, round metal branches, about 300 ft, 14 registers, insulated | $7,000 | $10,000 | $15,000 |
What moves the price
- Linear feet and register count
- Pros price by the run or by the foot: $10–$25 per linear foot for insulated flex including removal, $25–$55 for sheet metal. A 1,500 sq ft single-story has 150–250 ft of duct and 8–12 supply registers; a 2,500 sq ft two-story can have 350 ft and 18 registers.
- Material
- Insulated flex duct is the cheapest to buy and the fastest to install; it's standard in attics and crawl spaces. Sheet metal costs 2–3 times more installed, lasts 30+ years, moves air with less friction and is what a trunk-and-branch system on a two-story house needs. Duct board is a middle option some contractors use for plenums and trunks.
- Where the ducts are
- An open attic with a walkable path is the baseline. A crawl space with 18–24 inches of clearance adds 20–40%. Ducts inside finished walls, floors or a dropped ceiling mean opening and repairing drywall, and can double the price.
- Trunk and plenums
- Replacing only the branch runs and reusing the supply and return plenums is the cheapest job. A new plenum is $400–$1,500; a new fabricated metal trunk line is $1,500–$4,000 on its own.
- Sealing, insulation and testing
- R-8 insulated duct is code in unconditioned spaces. Mastic-sealed joints and a duct-leakage test (required at permit in many jurisdictions) add $300–$1,200 and are what makes the new system actually deliver the air.
- Design changes
- Like-for-like replacement is priced on the existing layout. Resizing runs to fix a room that never cools, adding returns, moving registers or zoning means a Manual D load-and-duct design, more fittings and more labor — often $1,000–$3,000 on top.
- Bundled with a new system
- Contractors discount ductwork 15–30% when it's done alongside a furnace, AC or heat-pump replacement, because the crew and the permit are already there. If the equipment is within a few years of replacement, price them together.
Common add-ons
| Add-on | Typical cost |
|---|---|
| New supply and return plenums | $400–$1,500 |
| Add a return-air duct and grille | $400–$1,500 |
| Mastic sealing and duct-leakage test | $300–$1,200 |
| Manual D design for resized or relocated runs | $500–$3,000 |
| Upgrade flex branches to sheet metal | $2,000–$8,000 |
| Drywall and ceiling repair for ducts in finished spaces | $500–$3,000 |
| Asbestos testing and abatement (pre-1980 duct tape or wrap) | $300–$4,000 |
| Zoning dampers and controller | $1,500–$4,000 |
| Mechanical permit and inspection | $50–$400 |
What it costs to do it yourself
A few damaged runs: $327–$587 and 3–5 hours
| Item | Cost | Note |
|---|---|---|
| Duct strap tensioning tool | $30 | Purchase · pulls nylon straps tight on collars; zip ties by hand leak |
| Aviation tin snips | $22 | Purchase |
| Respirator, gloves, coveralls, headlamp, knee pads | $45 | Purchase · old duct insulation and attic dust; fiberglass everywhere |
| Drill/driver with hex bits | $80 | Purchase · most homeowners already own this |
| Utility knife, tape measure, marker | $15 | Purchase · most homeowners already own this |
| Ladder and attic walk boards | $120 | Purchase · most homeowners already own this |
| R-8 insulated flex duct, 6–8 in | $150 | $45–$65 per 25 ft box; three boxes for a few runs, eight to ten for a house |
| Take-off collars, dampers and elbows | $25 | Materials |
| Duct mastic, foil tape and mesh | $32 | mastic on every joint; cloth duct tape is not a duct sealant |
| Nylon straps, hanger strap and inner-core zip ties | $23 | Materials |
| Disposal | $0–$60 | Dump fees, haul-away or bagging |
| Permit | $0–$200 | replacing a few runs rarely needs one; most jurisdictions require a mechanical permit and often a duct-leakage test for a whole-house replacement, and a few restrict HVAC work to licensed contractors — check before buying materials |
| Total (own common tools) | $327–$587 | typical $457 |
| Total (own nothing) | $542–$802 | buying every tool listed |
Whole house, flex ducts in the attic: $1,120–$1,518 and 14–24 hours
| Item | Cost | Note |
|---|---|---|
| Duct strap tensioning tool | $30 | Purchase · pulls nylon straps tight on collars; zip ties by hand leak |
| Aviation tin snips | $22 | Purchase |
| Respirator, gloves, coveralls, headlamp, knee pads | $45 | Purchase · old duct insulation and attic dust; fiberglass everywhere |
| Drill/driver with hex bits | $80 | Purchase · most homeowners already own this |
| Utility knife, tape measure, marker | $15 | Purchase · most homeowners already own this |
| Ladder and attic walk boards | $120 | Purchase · most homeowners already own this |
| R-8 insulated flex duct, 6–8 in | $495 | $45–$65 per 25 ft box; three boxes for a few runs, eight to ten for a house |
| Take-off collars, dampers and elbows | $83 | Materials |
| Duct mastic, foil tape and mesh | $106 | mastic on every joint; cloth duct tape is not a duct sealant |
| Nylon straps, hanger strap and inner-core zip ties | $76 | Materials |
| Register boots and grilles | $264 | $15–$30 per boot-and-grille set; reuse them if they're sound |
| Disposal | $0–$198 | Dump fees, haul-away or bagging |
| Permit | $0–$200 | replacing a few runs rarely needs one; most jurisdictions require a mechanical permit and often a duct-leakage test for a whole-house replacement, and a few restrict HVAC work to licensed contractors — check before buying materials |
| Total (own common tools) | $1,120–$1,518 | typical $1,319 |
| Total (own nothing) | $1,335–$1,733 | buying every tool listed |
Whole house, ducts in a crawl space: $1,182–$1,592 and 18–30 hours
| Item | Cost | Note |
|---|---|---|
| Duct strap tensioning tool | $30 | Purchase · pulls nylon straps tight on collars; zip ties by hand leak |
| Aviation tin snips | $22 | Purchase |
| Respirator, gloves, coveralls, headlamp, knee pads | $45 | Purchase · old duct insulation and attic dust; fiberglass everywhere |
| Drill/driver with hex bits | $80 | Purchase · most homeowners already own this |
| Utility knife, tape measure, marker | $15 | Purchase · most homeowners already own this |
| Ladder and attic walk boards | $120 | Purchase · most homeowners already own this |
| R-8 insulated flex duct, 6–8 in | $525 | $45–$65 per 25 ft box; three boxes for a few runs, eight to ten for a house |
| Take-off collars, dampers and elbows | $88 | Materials |
| Duct mastic, foil tape and mesh | $112 | mastic on every joint; cloth duct tape is not a duct sealant |
| Nylon straps, hanger strap and inner-core zip ties | $81 | Materials |
| Register boots and grilles | $280 | $15–$30 per boot-and-grille set; reuse them if they're sound |
| Disposal | $0–$210 | Dump fees, haul-away or bagging |
| Permit | $0–$200 | replacing a few runs rarely needs one; most jurisdictions require a mechanical permit and often a duct-leakage test for a whole-house replacement, and a few restrict HVAC work to licensed contractors — check before buying materials |
| Total (own common tools) | $1,182–$1,592 | typical $1,387 |
| Total (own nothing) | $1,397–$1,807 | buying every tool listed |
Two-story, sheet metal trunk and branches: $6,202–$6,762 and 40–70 hours
| Item | Cost | Note |
|---|---|---|
| Duct strap tensioning tool | $30 | Purchase · pulls nylon straps tight on collars; zip ties by hand leak |
| Aviation tin snips | $22 | Purchase |
| Hand seamer and crimper for metal pipe | $45 | Purchase |
| Respirator, gloves, coveralls, headlamp, knee pads | $45 | Purchase · old duct insulation and attic dust; fiberglass everywhere |
| Drill/driver with hex bits | $80 | Purchase · most homeowners already own this |
| Utility knife, tape measure, marker | $15 | Purchase · most homeowners already own this |
| Ladder and attic walk boards | $120 | Purchase · most homeowners already own this |
| Sheet metal trunk sections, snap-lock pipe, fittings and R-8 wrap | $5,100 | about $12–$18 per foot in materials; prefab trunk sections from an HVAC supply house |
| Take-off collars, dampers and elbows | $150 | Materials |
| Duct mastic, foil tape and mesh | $192 | mastic on every joint; cloth duct tape is not a duct sealant |
| Nylon straps, hanger strap and inner-core zip ties | $138 | Materials |
| Register boots and grilles | $480 | $15–$30 per boot-and-grille set; reuse them if they're sound |
| Disposal | $0–$360 | Dump fees, haul-away or bagging |
| Permit | $0–$200 | replacing a few runs rarely needs one; most jurisdictions require a mechanical permit and often a duct-leakage test for a whole-house replacement, and a few restrict HVAC work to licensed contractors — check before buying materials |
| Total (own common tools) | $6,202–$6,762 | typical $6,482 |
| Total (own nothing) | $6,417–$6,977 | buying every tool listed |
Hidden costs of DIY
- The layout is the design
- Like-for-like replacement copies the old system's sizing. If a room never got enough air, a new duct the same size won't fix it — that takes a Manual D calculation and probably a bigger run or a second register. Don't change diameters by guesswork; an undersized return or a too-small branch raises static pressure and shortens the life of the blower.
- Flex duct only works when it's pulled tight
- Flex loses capacity fast when it sags, kinks or takes tight bends: a run with 30% compression moves far less air than the same size pulled straight. Support every 4 ft with wide straps, no more than 1/2 in of sag per foot, gentle bends, and cut off the excess instead of snaking it. Most DIY duct problems are installation, not material.
- Duct tape is not a sealant
- Cloth duct tape dries out and falls off in an attic within a few years. Every collar, boot and plenum joint gets mastic (or UL 181 foil tape on clean metal), and the inner liner is strapped separately from the outer jacket. ENERGY STAR puts typical duct losses at 20–30% of the air moved; sealing is where a replacement pays back.
- Attic heat and crawl space misery
- Attics hit 130°F in summer; a crawl space is a place you crawl. Do the job in spring or fall, work in the morning, and plan on twice the hours you'd guess. This is the labor a contractor is charging for, and it's why the DIY saving looks so large.
- Old material may be asbestos
- Duct tape, wrap and vibration collars in homes built before about 1980 can contain asbestos. Don't tear into gray cloth tape or paper-faced wrap on an old system without a test ($300–$600); abatement, if needed, is a licensed job.
- The rest of the system
- New ducts on a 20-year-old air handler with a cracked plenum and a dirty coil don't fix the house. Check the plenum, the filter rack and the coil while it's all open, and consider timing the ductwork with equipment replacement — contractors discount the combination.
When to DIY and when to hire
DIY makes sense when
- The ducts are flex, in an attic or crawl space you can move through, and you're replacing them size-for-size on the same layout
- The plenums, boots and air handler are sound and you're keeping them
- You'll mastic every joint, strap every 4 ft and pull each run tight — and do it in cool weather
- Your jurisdiction lets a homeowner pull the mechanical permit, or none is needed for the scope
Hire a pro when
- The system is sheet metal, or you want to upgrade to it — trunk fabrication and fitting is a trade
- Rooms have never heated or cooled right, so the runs need resizing, a return added, or a Manual D design
- Ducts run inside finished walls, floors or ceilings
- You're replacing the furnace, AC or heat pump within a few years — bundle the ducts and take the discount
Why the DIY saving is so large — and where it stops
Duct replacement is a labor job. A box of R-8 insulated flex duct is $45–$65 and covers 25 feet; the collars, boots, mastic and straps to hang it are a few dollars each. What you’re paying a contractor for is the crew that spends a day in a 120°F attic cutting the old runs out, pulling new ones tight, strapping them every 4 feet and sealing every joint. The cost tables below show the result: $1,120–$1,518 for a 1,500 sq ft house in materials and tools, against $4,500 from a pro. Even a few damaged runs — a $750 minimum-charge job — is a $293 saving for an afternoon.
The number is honest, but it comes with a condition. It applies to replacing flex duct with flex duct, size for size, on the existing layout. A contractor’s whole-house job also includes things the DIY line doesn’t: checking whether the old layout was ever right, a new plenum if the old one is cracked, a leakage test, and a permit signed off by an inspector. If the rooms at the end of the run have never cooled, the fix is a Manual D design and probably bigger runs or a second return — not a new duct the same size. If the system is sheet metal, the trunk is fabricated and fitted, which is a trade. And if the ducts run inside finished walls, the job is half drywall. The DIY guide is written for the like-for-like flex job; the hire-a-pro page is for everything else.
How pros price it
By the run or by the linear foot, with a minimum. A quote should count the runs and registers, name the material and R-value, and say whether the plenums are replaced or reused. The lines that move the price most:
- Material — insulated flex at $10–$25 a foot installed; sheet metal at $25–$55.
- Access — attic baseline; crawl space +20–40%; finished walls and ceilings can double it.
- Trunk and plenums — $400–$1,500 for plenums, $1,500–$4,000 for a fabricated metal trunk.
- Sealing and testing — mastic on every joint and a leakage test, $300–$1,200, often required at permit.
- Design — resizing, added returns, zoning: $500–$3,000 more, plus the fittings.
- Timing — 15–30% off when bundled with new equipment.
Before anyone cuts a duct
Three things. Whether the old material is safe to touch — pre-1980 duct tape and wrap can contain asbestos, and that’s a test before it’s a project. Whether a permit and a licensed installer are required — most jurisdictions want a mechanical permit for a whole-house job, some want a leakage test, and a few don’t let homeowners do HVAC work at all. Whether the ducts are the problem — a $300 leakage test on a sound-looking system often finds that sealing, not replacement, is the fix. If the attic is being insulated at the same time, the spray foam comparison covers what a sealed attic does to ducts up there.
Run your own numbers. The ductwork replacement cost calculator prices it both ways: as DIY, with the tools you already own and a value on your time, or as a pro job at a low, typical or high quote with the add-ons that apply.
Frequently asked questions
How much does it cost to replace ductwork?
$3,000 to $7,000 for a typical 1,500 sq ft single-story house with flex ducts in the attic, typically about $4,500, including removal of the old ducts, new R-8 insulated flex, boots and grilles, sealing and a permit. On a crawl space expect $3,500–$8,000. A two-story house with a fabricated sheet metal trunk and branches runs $7,000–$15,000. Replacing just a few damaged runs is $450–$1,200 — mostly the contractor's minimum charge.
How much does ductwork cost per linear foot?
$10–$25 per linear foot installed for insulated flex duct, including tearing out the old run, and $25–$55 for sheet metal. Materials alone are $2–$3 a foot for flex ($45–$65 per 25 ft box of R-8) and $8–$18 for metal pipe with insulation wrap. A 1,500 sq ft house has 150–250 feet of duct; a 2,500 sq ft two-story can have 350 feet.
How much does it cost to replace ductwork in a 1,500 sq ft house?
About $4,500 with flex ducts in an attic — $3,000 on an easy job in an inexpensive market, $7,000 with new plenums, a leakage test and a difficult layout. On a crawl space, $3,500–$8,000. In sheet metal, $6,000–$11,000. A 2,000 sq ft house scales roughly with duct footage and register count: $4,000–$9,000 in flex, $7,000–$15,000 in metal.
Is it cheaper to replace ductwork yourself?
Much cheaper, for the right job. A whole-house flex replacement is $1,120–$1,518 in materials and tools against a $4,500 quote, because the contractor's price is mostly labor in an attic. A few damaged runs are $327–$587 against $750. The saving disappears when the job stops being like-for-like: a sheet metal system is $6,202–$6,762 in materials against $10,000 and needs fabrication skills, and any job that changes duct sizes or adds returns needs a Manual D design a homeowner can't do by eye.
How much does it cost to replace ductwork in an attic vs a crawl space?
An attic with a walkable path is the baseline: about $4,500 for a 1,500 sq ft house. A crawl space with 18–24 inches of clearance is $1,000–$1,500 more — $5,500 typical — because every duct is hung overhead while the installer lies on the ground. Ducts inside finished walls or a dropped ceiling are the expensive case: drywall opened and repaired, often $8,000 and up for the same house.
How much does it cost to replace ductwork in a mobile home?
$1,000 to $3,500, typically about $2,000. Mobile and manufactured homes use a single belly duct under the floor with short branch boots, so there's less material — but access is through the belly board and the crossover duct between double-wide sections is the usual failure point. Replacing the crossover alone is $300–$800. Check that the new duct is rated for manufactured housing; the boots and register sizes are different from site-built homes.
Should you replace ductwork when replacing the AC or furnace?
If the ducts are more than 15–20 years old, leaky, undersized for the new equipment, or made of a material that's failing — yes, and do it at the same time. Contractors discount ductwork 15–30% when the crew and permit are already there for the equipment, and a new high-efficiency system on old, leaky, undersized ducts won't perform to its rating. Sound ducts under 15 years old just need sealing and a leakage test, $300–$1,200.
How long does ductwork last?
Flex duct 10–20 years; the plastic inner liner gets brittle and the outer jacket tears, and rodents open it. Duct board 15–25 years. Sheet metal 30–50 years, usually outliving the house's equipment twice over, though the tape and insulation on it fail sooner. Signs it's time: rooms that never get enough air, dust and insulation blowing from registers, visible crushed or disconnected runs, and energy bills that climbed after the last equipment replacement.
Is replacing ductwork worth it?
When the ducts are leaking, crushed or undersized, yes — ENERGY STAR puts losses in typical systems at 20–30% of the air moved, and a sealed, insulated, properly sized replacement recovers most of that in comfort and bills. When the ducts are sound and just old, sealing and insulating them ($300–$1,200) captures most of the benefit for a fraction of the cost. Get a duct-leakage test before deciding: it tells you whether you have a sealing problem or a duct problem.
Sources
- Heating, Air Conditioning, and Refrigeration Mechanics and Installers (SOC 49-9021), Occupational Employment and Wage Statistics , U.S. Bureau of Labor Statistics, 2026-04
- How Much Does It Cost to Install or Replace Ductwork? , HomeGuide, 2026-09
- How Much Does Duct Replacement Cost? , Angi, 2026-09
- How Much Does It Cost to Install Ductwork? , HomeAdvisor, 2026-09
- Duct Sealing , ENERGY STAR, U.S. Environmental Protection Agency, 2026-09
- Minimizing Energy Losses in Ducts , U.S. Department of Energy, 2026-09
- International Residential Code, Chapter 16: Duct Systems , International Code Council, 2026-09
- Manual D: Residential Duct Systems , Air Conditioning Contractors of America, 2026-09
Figures last reviewed . See how we estimate.