Ductwork Replacement Cost

National cost range

Low end

$1,500

Simple access, like-for-like

Typical

$4,500

What most jobs come in at

High end

$10,000

Upgrades, difficult access, code work

What you are actually paying for

Find the row that matches your situation. Quotes that differ wildly from each other usually differ in scope, not in price.

What moves the price

In descending order of impact. These are also the questions worth asking a contractor whose quote sits outside the range above.

1. 1

   Extent of replacement

   Replacing a section of trunk duct in an accessible attic is far cheaper than a whole-house duct replacement that requires opening walls and ceilings.

2. 2

   Duct material

   Sheet metal trunk with flex runouts is standard. All sheet metal costs more but lasts longer. Duct board is cheaper but more fragile.

3. 3

   Insulation and sealing

   Ducts in unconditioned spaces (attic, crawlspace) must be insulated to R-8 or better. Mastic sealing at every joint is code in most jurisdictions and adds labor.

4. 4

   Accessibility

   Attic ductwork is accessible. Ducts inside walls or between floors require drywall removal and repair.

5. 5

   Return duct adequacy

   Many replacements address undersized returns — adding return duct capacity often requires new wall or floor grilles and additional trunk routing.

Direct answer

Whole-home ductwork replacement in 2026 typically costs $1,500 to $10,000 nationally, with partial attic or crawl replacements often quoted $4,000 to $8,000 for average single-family homes. Flex versus metal trunk lines, insulation R-value, zoning dampers, and accessibility in tight attics explain most variance. Duct work is frequently bundled with HVAC equipment changeouts—standalone duct quotes should state whether returns, supplies, and boots are all included.

What each price band actually buys

Low end

Replace failed flex runs in crawlspace, seal connections, minimal insulation upgrade.

Typical

Attic trunk and branch replacement with R-8 insulation, sealed boots, new grilles.

High end

Metal trunks, zoning system, drywall repair after soffit builds, engineering for static pressure.

Labor vs materials

Typical split for this job nationally: roughly 60% labor and 40% materials. Crew size is usually 2–4 HVAC installers, across two to four days for full replacement.

What this price usually does not include

• HVAC equipment replacement unless bundled
• Asbestos abatement on wrapped ducts
• Drywall and paint for dropped soffits unless scoped
• Whole-house balancing with room-by-room load redesign
• Insulation upgrade in walls unrelated to ducts
• Cleaning-only services marketed as replacement

Hidden costs that show up on real jobs

Regional variation

Attic duct markets in the South see more full replacements than basement duct markets in the Midwest. Labor for crawling tight attics scales with metro wages. Localized `/home/cost/ductwork-replacement/[metro]` data helps when comparing sealed metal versus flex systems—verify insulation climate zone requirements in the bid.

Code upgrades this job can trigger

• Insulation R-values per IECC climate zone
• Sealing to mastic or UL-listed tape standards
• Fire dampers where ducts penetrate rated assemblies
• Condensate and condensate-sensitive duct routing in unconditioned spaces
• Smoke detector interlock where local amendments require

Repair vs replace

Seal and repair when ducts are structurally sound but leaky—duct blasting tests often show 20–30% leakage fixable without full replacement. Replace when flex is brittle, insulation is missing, mold contaminates porous liner, or static pressure cannot support new heat pump airflow. Partial replacement of the worst attic runs is viable when crawl supplies are sound. If you are buying high-efficiency HVAC, committing leaky ducts wastes the equipment premium—invest in sealing or replacement first.

Timeline and visits

Partial replacements may take one to two days; whole-home jobs two to four days plus any drywall trades. Testing and balancing add another visit.

Quote checklist — line items a fair bid should show

1. Linear feet or area of duct replaced versus sealed only
2. Material type: flex, sheet metal, duct board
3. Insulation R-value and vapor barrier
4. Return and supply grille counts
5. Boot and damper replacements
6. Leakage test target (e.g., post-repair CFM25)
7. Drywall or soffit repair scope
8. Permit if mechanical permit bundles duct work

Questions to ask before you sign

• Will you perform a blower door or duct leakage test before and after?
• Are all boots and grilles included or reuse old?
• How do you handle asbestos-wrap ducts if present?
• Will new ducts meet static pressure needs of my heat pump?
• Who patches drywall after soffit installs?
• Is equipment replacement required for warranty if ducts are undersized?

Quote red flags for this job

• Seal-only quote on collapsed flex duct
• No insulation R-value specified for attic runs
• Ignores return air sizing
• Bid by lump sum without supply/return counts
• No test-out procedure after install
• Promises major efficiency gains without leakage baseline

Payment schedule norms

Progress payments at demo, rough install, and test-out are reasonable on large duct jobs; avoid paying full amount before leakage test results.

Seasonality

Attic work is miserable in midsummer—spring and fall improve crew productivity and your comfort if registers are offline.

Can you do it yourself?

When this cannot wait

• Rooms that never get enough airflow despite a running system
• Visible disconnected or collapsed flex duct in the attic
• Energy bills high with a system that runs constantly
• New HVAC equipment performing below its rated efficiency due to duct losses

Common questions