How much does it cost to install or replace ductwork?
Ashburn, VA

How much does it cost to install or replace ductwork?

Ashburn, VA

How much does it cost to install or replace ductwork?

$1,400 – $5,600average ductwork replacement cost
$270 – $500cost per duct run (replacement)
$25 – $55cost per linear foot (replacement)

New ductwork costs $1,400 to $5,600 to install or replace. Air duct replacement costs $25 to $55 per linear foot or $270 to $500 per duct. Adding a vent to existing ductwork costs $250 to $500. HVAC ductwork repair costs $200 to $700 for minor leaks. Duct sealing costs $400 to $2,700.

Get free estimates for your project or view our cost guide below:

$1,400 – $5,600 average ductwork replacement cost

$270 – $500 cost per duct run (replacement)

$25 – $55 cost per linear foot (replacement)


New ductwork costs $1,400 to $5,600 to install or replace. Air duct replacement costs $25 to $55 per linear foot or $270 to $500 per duct. Adding a vent to existing ductwork costs $250 to $500. HVAC ductwork repair costs $200 to $700 for minor leaks. Duct sealing costs $400 to $2,700.

Get free estimates for your project or view our cost guide below:
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Cost to replace ductwork

The average cost to replace ductwork is $1,400 to $5,600, depending on the home's size. Air duct replacement costs $25 to $55 per linear foot or $270 to $500 per duct for a crawl space, attic, or basement. New ductwork installation costs $2,400 to $6,600 for a house without HVAC ducts.

Cost to replace ductwork by house size - chart
Cost to replace ductwork by house size - chart
Cost to replace ductwork
Home size (square feet) Average cost
1,000 – 1,500 $1,400 – $3,400
1,500 – 2,000 $2,100 – $4,500
2,000 – 2,500 $2,800 – $5,600
2,500 – 3,000 $3,500 – $6,700
3,000 – 3,500 $4,200 – $7,800
3,500 – 4,000 $4,900 – $9,000

  • Initial duct inspections cost $40 to $100 for duct-replacement quotes.

  • Ductwork lasts 10 to 20 years on average.

  • Installing new ducts takes 1 to 2 days.

  • Homeowners who replace leaky ducts save 10% to 40% on energy bills.

Get free estimates from duct installers near you.

Ductwork cost calculator

The following table shows the average cost to replace ductwork.

Average ductwork cost - chart
Average ductwork cost - chart
Average ductwork cost
National average cost $3,500
Minimum cost $1,000
Maximum cost $8,000
Average range $1,400 to $5,600

*Cost data is based on 399 project costs reported by HomeGuide members.

New ductwork installation cost

New ductwork installation costs $2,400 to $6,600 on average to retrofit an existing home without ducts.

A new duct system includes:

  • Plenum

  • Fittings

  • Air-distribution boxes

  • Duct runs

  • Dampers

  • Insulated register boots

New ductwork installation cost - chart
New ductwork installation cost - chart
Ductwork installation cost
Install type Cost per linear foot Average cost
Ductwork replacement $25 – $55 $1,400 – $5,600
New duct installation / retrofit $40 – $65 $2,400 – $6,600

Air duct replacement system installed in house attic
Air duct replacement system installed in house attic

Commercial ductwork cost per square foot

Installing commercial ductwork costs $15 to $35 per linear foot on average, depending on the ductwork size, location, and access. Commercial jobs require customized, large-scale duct designs.

Air duct replacement cost

Residential ductwork installation costs $25 to $55 per linear foot on average to remove the existing ducts and install new ductwork. The average home has 100 linear feet of ductwork.

Air duct replacement cost by location - chart
Air duct replacement cost by location - chart
Air duct replacement cost by location
Interior location Average cost
Crawl space $3,000 – $7,300
Attic $2,200 – $5,600
Basement $1,800 – $3,100
Mobile home $1,000 – $3,300

*Includes materials and labor.

Cost to replace ductwork in a crawl space

Replacing ductwork in a crawl space costs $3,000 to $7,300 on average, depending on the size, condition, and accessibility. Duct contractors recommend cleaning, repairing, or encapsulating the crawl space before installing new ducts.

Cost to replace air ducts in an attic

Replacing ductwork in an attic costs $2,200 to $5,600 on average, depending on the accessibility and system size. Adding attic insulation costs $800 to $1,500.

Attic duct insulation improves energy efficiency in unconditioned attics and prevents AC units from overworking.

Contractor installing new ductwork retrofit in house attic
Contractor installing new ductwork retrofit in house attic

Cost to replace ductwork in basement

The cost to replace ductwork in a basement is $1,800 to $3,100 on average. Basement ductwork replacements are typically the cheapest since the ducts are easy to access.

Exposed ductwork cost

Exposed ductwork costs $10 to $33 per linear foot installed. Exposed ducts are easier to access than concealed ductwork. However, ductwork prices increase for open ceilings because of the more expensive materials, painting, and longer install time.

Mobile home ductwork cost

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Mobile home ductwork replacement costs $1,000 to $3,300 on average, depending on the mobile home size, duct material, and accessibility. Ductwork in mobile homes is typically under the floor with the insulation, which makes replacement difficult.

Cost factors to replace ductwork in a house

The total cost to replace ductwork depends on the house size, duct location, number of ducts, duct type, and insulation. Labor costs increase for rerouting ductwork, cutting into the floor or ceiling, or installing ducts in older homes.

Cost factors to replace ductwork in a house
Service Average cost
Home energy audit $200 – $500
Adding a vent to existing ductwork $250 – $500
Duct insulation $800 – $2,000
Asbestos inspection & testing $250 – $700
Asbestos removal $700 – $2,200
Mold inspection & testing $200 – $650
Mold remediation $450 – $6,000
Permits $50 – $250

Additional fees may apply for:

  • Drywall repair costs $150 to $325.

  • Ceiling repair costs $300 to $1,200 on average or $50 to $100 per square foot.

  • Drop-ceiling tile replacement costs $2 to $4 per square foot.

  • Installing a new ceiling grid and tiles costs $3 to $7 per square foot.

Cost to add a vent to existing ductwork

Adding a vent to existing ductwork costs $250 to $500, depending on the home layout. Adding additional HVAC air vents lowers the overall system efficiency and raises utility bills.

Ductwork material costs

Ductwork material costs vary by size and shape. Duct installers use different duct types depending on the location, building codes, and HVAC system requirements.

Ductwork material costs
Duct type Material cost per linear foot Facts
Flexible non-insulated $1 – $3
  • May have wire reinforcement
  • Often covered with plastic or aluminum
  • Lightweight and easy to install
  • Great for tight spaces and complex layouts
  • Prone to tears, pest infestations, & moisture damage
  • Reduced airflow without proper installation
  • Creates fire hazards in high-heat areas
  • Shortest lifespan of all types
Flexible insulated $2 – $4
  • For unconditioned spaces
  • Lightweight
  • Can breed mold & suffer moisture damage
Fiberglass / fiberboard $4 – $6
  • Requires less supports than metal ducts
  • Doesn’t tolerate moisture 
  • Doesn’t need additional insulation
  • Ideal for long, straight duct lines
Sheet metal $7 – $13
  • Rigid in shape
  • Made from galvanized steel or aluminum
  • Best for straight duct-run lines or exposed ducts
  • Available with fiberglass lining for insulation
  • Mold-resistant
  • Long lifespan
  • Best with external duct insulation

*Not including installation or contractor mark-up.

Cost to insulate ductwork

Duct wrap insulation costs $800 to $2,000 on average for materials and labor. Duct insulation costs $1 to $8 per square foot installed, depending on the home’s size, materials, and accessibility.

Duct wrap insulation cost
Insulation type Total cost installed per square foot
Fiberglass (flexible) $1 – $4
Fiberglass (rigid / foam board) $4 – $8
Mineral wool (flexible) $2 – $4

Contractor installing insulated air ducts in home basement
Contractor installing insulated air ducts in home basement

Cost to move ductwork

Relocating or moving ductwork costs $25 to $55 per linear foot. Moving ductwork requires ripping out the old ducts and installing new ducts in the new location.

Asbestos and mold in air ducts

Installing ductwork in an older home may require removing hazardous materials like asbestos or mold first. Homes built during or before the 1970s often have asbestos duct insulation.

Ductwork permits and regulations

building permit costs $50 to $250 for installing new ductwork. Permits for replacing ducts as part of a full HVAC system install cost $250 to $1,500.

  • Permit fees depend on local code regulations and other HVAC connections.

  • Contractors typically pull all permits and manage inspections.

HVAC ductwork installation cost

  • The average cost to install an HVAC system with ductwork is $7,000 to $16,000 for retrofits in existing homes.

  • Installing new heating and cooling units with existing ducts costs $5,000 to $11,000 on average.

  • New HVAC ductwork installation costs $2,400 to $6,600 on average.

Cost to replace hvac ducts
HVAC unit type HVAC unit cost installed HVAC unit with ductwork cost
Central air conditioner $3,300 – $5,900 $4,700 – $11,500
Furnace $2,000 – $5,400 $3,400 – $11,000
Heat pump $3,800 – $8,200 $5,200 – $13,800
Geothermal heat pump $15,000 – $35,000 $16,400 – $40,600

Residential ductwork system installed in new construction
Residential ductwork system installed in new construction

Adding central air conditioning

Installing a new air conditioning unit costs $3,300 to $5,900 with existing ductwork. AC duct replacement costs $1,400 to $5,600 more for upgrading old ductwork that’s damaged or too small for the new unit.

Upgrading a forced-air heating system

Get free estimates from duct installers near you.

Installing a new furnace and ductwork costs $3,400 to $11,000. Furnace ductwork prices alone are $1,400 to $5,600 for replacements, or $2,400 to $6,600 for new installations in existing homes.

Ductwork repair cost

Ductwork repair costs $200 to $700 on average for minor jobs, depending on the service, duct size, and accessibility.

  • Basic repairs include fixing a leak, replacing a vent, or replacing small duct sections or insulation.

  • Larger damages need a full sealant application or duct replacements.

Ductwork repair cost
Repair Average cost
Minor repairs $200 – $700
Air duct cleaning $300 – $700
Aeroseal sealing $1,300 – $2,700
Manual sealing $400 – $1,900
Duct Armor $5,000 – $30,000

Air duct cleaning

Air duct cleaning costs $300 to $700 on average or $25 to $45 per vent.

Professional duct cleaning includes:

  • All supply and return air ducts

  • Dryer vents

  • Grills

  • Furnace connections

  • AC blower

Duct sealing cost

Air duct sealing costs $400 to $1,900 for manual sealing with mastic sealer or tape. Aerosol duct sealing costs $1,300 to $2,700 for injecting hot polymer glue inside the air ducts.

Duct sealing cost
Method Average cost Features
Manual $400 – $1,900
  • External application
  • Best for large holes or leaky connections
  • May require cutting walls & ceilings
  • Ideal for exposed & easy-access ducts
Aerosol $1,300 – $2,700
  • Internal application
  • Seals cracks up to 5/8 inches wide
  • Seals entire duct interior
  • Best for hard-to-reach places

Benefits of duct sealing:

  • Raises energy efficiency by 10% to 40% after repairing all leaks

  • Improves indoor air quality

  • Distributes heating evenly throughout the home

Duct Armor cost

Duct Armor costs $5,000 to $30,000, depending on the ductwork size, type, condition, accessibility, and prep work. Installers spray this sealant inside ducts to create a ¼” thick rubberized duct liner that completely coats, seals, and restores old ductwork.

Duct Armor uses and benefits:

  • Prevents pest infestations

  • Stops air leaks

  • Seals cracks, rust, and water damage

  • Encapsulates asbestos

  • Stabilizes old fiberglass ductwork

  • Eliminates smoke odors after a fire

  • Not suitable for flex ducts with holes larger than 0.5 inch

Ductwork replacement FAQs

What is ductwork?

  • Ductwork is a large piping system that sends heated or cooled air from HVAC units throughout the home.

  • Duct vents are long tubes or rectangular sheet-metal channels made of fiberglass, steel, PVC, or aluminum.

  • These rigid or flexible ducts are in ceilings, attics, basements, and crawl spaces.

How long does it take to replace ductwork?

Replacing ductwork takes 1 to 2 days on average or up to 4 days for larger homes or complex projects. Installation time depends on the home’s size, age, number of HVAC units, duct type, and crew size. Allow more time when wall or ceiling repairs are necessary.

How often should ductwork be replaced?

Ductwork lasts 10 to 20 years on average before it needs replacing. Most ducts need work when upgrading to bigger or higher-efficiency units.

Signs to repair or replace ductwork:

  • Unbalanced heating or cooling

  • Rising energy bills

  • Reduced airflow

  • Noisy HVAC system with vibrating ducts

  • Consistently dusty home

  • Mold, odors, or moisture damage in air ducts

  • Pest infestations in the ductwork

  • Collapsed, loosened, torn, or rusted duct sections

  • When replacing HVAC systems more than 15 years old

Does ductwork need to be insulated?

Ductwork in unconditioned spaces needs insulation. Duct insulation reduces energy bills by 10% to 40%, prevents condensation, and makes the ducts last longer. Very cold, hot, and humid climates benefit most from duct insulation.

Can you use flex ducts in a crawl space?

You can use flex ducts in a crawl space that stays dry with full encapsulation that blocks out all pests. Flex ducts always need insulation in unconditioned crawl spaces, and they should hang above the ground. Especially in humid climates, rigid metal ducts last longer in unconditioned crawl spaces.

Do you need to replace ductwork when replacing an AC unit?

You should replace ductwork when replacing an AC unit if the ducts are moldy, more than 20 years old, or cracked. HVAC installers inspect ducts first and recommend cleaning, repairing, or replacing ducts as needed.

Do heat pumps require ductwork?

Heat pumps can have mini-split systems with or without ductwork. Conventional air-source heat pumps need ducts to move air through the home. Ductless systems circulate refrigerant through small conduit lines from outdoor compressors to indoor blower units.

Can I install my own ductwork?

DIY ductwork replacement is illegal in most states without a license. Hire certified HVAC contractors for duct installation and repairs.

Risks of DIY ducting include:

  • Failing home inspections

  • Forfeiting home insurance and HVAC warranties

  • Leaky ducts that raise utility bills

  • Damage to the home and HVAC units

Hiring a professional duct installer

Hire ductwork contractors who install ductwork properly to meet all building code standards.

When choosing an air duct contractor:

Questions to ask duct installers

  • Which duct type is best for my home?

  • How many duct installations have you done?

  • Can I see photos of your past work?

  • Can you provide references from previous ductwork projects?

  • What does your labor warranty cover?

  • If installing flex ducts, will you add supports every 4 feet?

  • Can you install ducts in air-conditioned areas to reduce energy losses?

  • Will you insulate the entire length of all supply lines?

  • Do you use rigid connectors and sealant on flex-duct connections?

  • Will you test for duct leaks after installation?

  • Do you use Manual D duct-design calculation software to size the ducts?

  • Can you also make Manual J and Manual T calculations to check the supply-register sizes?

  • Do your prices include a home energy audit to prevent leaks and optimize airflow?

  • Will you pull permits for this duct installation, and how much do they cost?

  • Does this estimate include all labor, materials, and cleanup costs?

  • How long will this duct installation take?