The average cost to install new ductwork is $2,500 to $7,500, with most homeowners paying around $4,500 for a complete duct system in a standard 1,500- to 2,500-square-foot home. Per linear foot, ductwork runs $15 to $55 installed depending on material, diameter, and accessibility. A simple single-zone system in an open basement or attic starts as low as $1,500. A full multi-zone system routed through finished walls, tight crawl spaces, or between floors in a two-story home can push past $12,000. Estimate your project with the ductwork replacement cost calculator.

Ductwork is the circulatory system of your HVAC — it carries conditioned air from the furnace or air handler to every room and returns stale air back for reconditioning. When it's undersized, leaky, disconnected, or deteriorated, no furnace or AC unit in the world will heat and cool the house evenly. New ductwork is often the fix that makes an HVAC upgrade actually deliver the comfort it promised.

Ductwork Installation Cost at a Glance

Cost Detail	Amount
National average	$4,500
Typical range	$2,500 – $7,500
Low end (small home, open access)	$1,500 – $2,500
High end (large home, multi-zone, concealed runs)	$8,000 – $12,000+
Cost per linear foot	$15 – $55
Cost per vent/register run	$250 – $700
Average total duct length (whole house)	150 – 350 linear feet
Typical job duration	2 – 4 days

Ductwork Cost by Material

The duct material affects price, performance, longevity, and how easily the system fits into your home's structure. Most residential systems use one material or a combination of two.

Material	Cost Per Linear Foot (Installed)	Whole-House Estimate	Lifespan
Flexible duct (flex)	$10 – $25	$1,500 – $5,000	15 – 25 years
Sheet metal (galvanized steel)	$20 – $45	$3,000 – $9,000	25 – 50+ years
Fiberboard	$15 – $30	$2,200 – $6,000	15 – 25 years
Aluminum	$18 – $40	$2,700 – $8,000	20 – 35 years
Fiberglass-lined sheet metal	$25 – $55	$3,800 – $10,000	25 – 50+ years

Flexible Duct

Flex duct is the most affordable and the easiest to install. It's a wire-coil skeleton wrapped in insulation and a plastic vapor barrier, and it bends around obstacles without fittings. Most residential new construction and retrofits use flex for branch runs — the individual lines from the trunk to each register. The downside is airflow resistance. Flex duct that's kinked, sagging, or too long creates turbulence and pressure drop, which makes the HVAC system work harder. Proper support and straight, taut runs are essential for performance.

Sheet Metal

Galvanized steel is the premium residential standard. It's rigid, smooth-walled, and moves air with the least resistance of any duct material. It also lasts the longest — 25 to 50+ years if the joints stay sealed. The trade-off is cost and installation time. Every turn needs a fabricated elbow, every branch needs a takeoff fitting, and every joint needs mastic or foil tape and mechanical fasteners. Sheet metal trunks with flex branches is the most common hybrid approach, balancing cost and performance.

Fiberboard

Fiberboard duct is rigid fiberglass pressed into panels and assembled on-site. It's lighter than metal, provides built-in insulation, and dampens noise. It costs less than sheet metal but more than flex. The concern with fiberboard is moisture — if it gets wet from condensation or a leak, it can grow mold inside the duct, which circulates spores through the house. It's best suited for dry climates and conditioned spaces where condensation risk is low.

Fiberglass-Lined Sheet Metal

This is the quietest option — a sheet metal duct with fiberglass insulation bonded to the interior wall. It reduces both noise transmission and thermal loss. It's common in high-end residential and light commercial applications. The liner adds $5 to $15 per linear foot over bare sheet metal and needs periodic inspection to ensure the fiberglass isn't deteriorating and shedding fibers into the airstream.

Ductwork Cost by Home Size

Home Size	Approximate Duct Length	Number of Vents	Installed Cost (Flex/Metal Mix)
Under 1,000 sq ft	80 – 150 ft	6 – 10	$1,500 – $3,500
1,000 – 1,500 sq ft	120 – 200 ft	8 – 14	$2,000 – $5,000
1,500 – 2,500 sq ft	180 – 300 ft	12 – 20	$3,000 – $7,500
2,500 – 3,500 sq ft	250 – 400 ft	16 – 26	$4,500 – $10,000
3,500+ sq ft	350 – 550+ ft	22 – 35+	$6,500 – $12,000+

Vent count matters as much as total duct length. Each vent requires a branch run from the trunk line, a boot fitting at the wall or floor, a register grille, and the labor to cut, connect, and seal everything. A 2,000-square-foot home with 16 vents costs more than the same house with 12 vents, even if the total duct length is similar, because each additional vent adds $250 to $700 in material and labor.

Ductwork Cost by Project Type

Not all ductwork projects are the same scope. Replacing existing ducts, extending to a new room, and installing a complete system from scratch are three very different jobs.

Project Type	Typical Cost	When It Applies
Full duct system (new construction)	$2,500 – $7,500	New build, gut renovation, or home with no existing ductwork
Full duct replacement	$3,000 – $9,000	Old, deteriorated, or undersized ducts being torn out and replaced
Partial replacement (trunk or branches)	$1,000 – $4,000	Specific sections failing while the rest is sound
Extend to new room or addition	$500 – $2,500	Home addition, finished basement, converted garage
Add a single vent run	$250 – $700	One room that's too hot or too cold
Duct sealing and insulation only	$1,000 – $3,500	Existing ducts are in good shape but leaking or uninsulated

New Construction vs. Replacement

Installing ducts in new construction costs less than replacing them in an existing home because the walls, floors, and ceilings are open — the installer can see everything, reach everything, and run ducts along the shortest path. Replacement in a finished home means working around closed walls, cutting access holes, fishing ducts through tight spaces, and patching everything afterward. That added difficulty increases labor by 25% to 50%, which is why replacement typically costs $500 to $2,000 more than new installation for the same house size.

Extending Ducts to an Addition

Running ductwork to a new room, a home addition, a finished basement, or a garage conversion costs $500 to $2,500 depending on the distance from the existing trunk line and how many new vents are needed. The HVAC system also has to be evaluated — adding duct runs to a system that's already at capacity just weakens airflow to every room. If the existing furnace or air handler can't support the extra load, you may be looking at a full HVAC installation or at minimum a mini-split installation for the new space instead.

What Affects the Cost of Ductwork Installation?

Accessibility

This is the single biggest variable after material choice. Ducts routed through an open, unfinished basement or a wide-open attic install quickly and cheaply. Ducts that need to run through finished walls, between floor joists with limited clearance, or through a cramped crawl space take two to three times as long. If walls need to be opened, budget for drywall repair and interior painting afterward — costs that are often excluded from the HVAC contractor's quote.

Number of Zones

A single-zone system uses one thermostat and one set of ducts to condition the entire house. A multi-zone system divides the house into two or more independently controlled zones — typically upstairs/downstairs or sleeping/living areas — each with its own thermostat and motorized dampers. Zoning adds $1,500 to $4,000 to the ductwork cost because the installer has to add dampers, zone controllers, and additional thermostats, plus design the duct layout to handle variable airflow without creating pressure problems.

Insulation Requirements

Ducts running through unconditioned spaces — attics, crawl spaces, garages — must be insulated to prevent energy loss and condensation. Insulation adds $2 to $8 per linear foot depending on the R-value and whether it's a wrap, a liner, or a pre-insulated duct. In an attic that can reach 140°F in summer, uninsulated ducts lose 25% to 40% of the conditioned air before it reaches the room. Proper duct insulation works alongside the home's overall house insulation strategy. If the attic insulation itself is thin or missing, addressing that at the same time — see attic insulation pricing — multiplies the energy savings.

Duct Design and Sizing

Properly sized ductwork requires a Manual D calculation — an engineering process that determines the size, length, and layout of every trunk and branch based on the home's heating and cooling loads. An oversized duct wastes material and money. An undersized duct creates noise, restricted airflow, and rooms that never reach the set temperature. Many contractors skip the calculation and size by rule of thumb, which often results in an imbalanced system. A Manual D design costs $200 to $500 if billed separately, but quality contractors include it in the installation price.

Old Duct Removal

If you're replacing existing ductwork, the old system has to come out first. Removing old flex duct from an attic is straightforward — $300 to $800 for a whole house. Removing old sheet metal from between joists, inside soffits, or through wall chases is more labor-intensive — $500 to $2,000. If the old ducts contain asbestos-wrapped insulation (common in homes built before 1980), asbestos removal requirements apply, which adds $1,500 to $5,000+ depending on the extent.

Geographic Location

HVAC labor rates vary 30% to 50% between markets. A full duct system in a mid-size Midwestern city costs $3,000 to $5,000. The same system in New York, San Francisco, or Boston runs $5,000 to $8,000+. Local building codes also vary — some jurisdictions require duct leakage testing, specific insulation levels, or fire dampers at certain penetrations, all of which add material and inspection costs.

Ductwork Installation vs. Duct Repair

Not every duct problem requires full replacement. Here's how to tell whether you need new ducts, a repair, or just sealing and cleaning.

Solution	Cost	When It Makes Sense
Air duct cleaning	$300 – $700	Ducts are structurally sound but dirty, dusty, or musty
Duct sealing (mastic + tape)	$1,000 – $3,000	Ducts are intact but leaking at joints — common in flex systems
Duct insulation (add or replace)	$800 – $2,500	Ducts in unconditioned spaces lack insulation or have damaged wrap
Partial duct replacement	$1,000 – $4,000	One section is crushed, disconnected, or deteriorated
Full duct replacement	$3,000 – $9,000	System-wide deterioration, undersizing, or code issues
Full new duct system	$2,500 – $7,500	No existing ductwork (conversion from radiant, baseboard, or window units)

A duct leakage test — typically $200 to $400 — tells you exactly how much conditioned air is escaping before it reaches the rooms. The Department of Energy estimates that leaky ducts waste 20% to 30% of the energy your HVAC system produces. If the ducts are less than 20 years old and structurally sound, sealing the joints and adding insulation can recapture most of that loss for a fraction of the cost of replacement. If the ducts are crushed, disconnected, mold-contaminated, or sized for a system that no longer exists, replacement is the only real fix.

Signs You Need New Ductwork

Uneven temperatures room to room: Some rooms are always too hot or too cold despite a functioning HVAC system. This typically means undersized ducts, blocked runs, or disconnected sections.
High energy bills with no explanation: If your HVAC system is relatively new and properly maintained but energy costs are climbing, the ducts may be leaking conditioned air into the attic or crawl space.
Visible damage: Crushed flex duct in the attic, disconnected joints, holes, or ducts hanging from their supports are obvious signs of failure.
Excessive dust: If the house is dusty no matter how often you clean, leaky ducts may be pulling attic insulation particles, crawl space debris, or outdoor air into the supply stream.
Musty or stale odors from the vents: Mold or moisture inside the ductwork — especially in fiberboard ducts or uninsulated metal in humid climates — circulates odors and spores throughout the house. An air duct cleaning may resolve mild cases, but mold-contaminated fiberboard usually needs to be replaced entirely.
Noisy operation: Popping, rattling, whooshing, or whistling from the ducts when the system runs indicates loose connections, undersized runs, or restrictions that force air through too-small openings.
Ductwork age: Flex duct and fiberboard have a 15- to 25-year lifespan. Sheet metal lasts longer but the joints and seals degrade over time. If the ducts are original to a home built before 2000, they're likely due for at minimum a seal-and-insulate service, if not full replacement.

When to Replace Ductwork vs. Install a Ductless System

Option	Cost	Best For
New ductwork + central HVAC	$7,000 – $18,000 (ducts + equipment)	Whole-house comfort, consistent temperatures, filtration
Ductless mini-splits	$3,000 – $8,000 (1 – 4 zones)	Homes with no duct access, additions, targeted zone control

If your home currently has no ductwork — common in older homes with radiators, baseboard heat, or window AC units — you have a choice between installing ducts for a central system or going ductless with mini-split installation. Mini-splits avoid the cost and disruption of running ducts through finished walls and ceilings, and they offer room-by-room temperature control. But they cost more per zone than a single ducted system, they require a wall-mounted head unit in each room, and they don't filter and circulate air as effectively as a central system. For a full comparison including the equipment side, see HVAC installation costs.

What to Bundle With New Ductwork

If you're tearing out and replacing ductwork, the walls and ceilings are already open and the HVAC contractor is already on-site. That makes it the cheapest time to handle related projects.

HVAC system replacement: Pairing new ducts with a new furnace and air conditioning unit ensures the equipment and distribution system are matched for maximum efficiency. A mismatched system — new equipment on old, leaky ducts — wastes 20% to 30% of the capacity you just paid for.
Attic insulation: If the ducts run through the attic, upgrading the attic insulation at the same time improves the thermal envelope for both the ducts and the living space below. Spray foam insulation on the attic roofline brings the entire attic into the conditioned space, which eliminates duct insulation concerns entirely.
Crawl space encapsulation: For ducts in the crawl space, crawl space encapsulation seals and conditions the area, reducing moisture damage and energy loss. It's a natural companion to any below-floor duct replacement.
Dryer vent installation: While the HVAC crew is in the walls and ceilings, adding or rerouting a dryer vent is a minor add-on.
Drywall and painting: Duct replacement in finished spaces requires cutting access holes. Budget for drywall repair and interior painting to close everything back up — these are often excluded from the HVAC contractor's bid.

How to Save on Ductwork Installation

Use flex duct for branch runs. A hybrid system with a sheet metal trunk and flex branches costs 20% to 40% less than an all-metal system and performs nearly as well when the flex is properly supported and run in short, straight lengths.
Bundle with HVAC replacement. Buying ducts and equipment from the same contractor in a single project gets you a package price and one mobilization instead of two. Many contractors discount ductwork when it's part of a full furnace and AC replacement.
Choose accessible routing. Ducts run through an open attic or basement cost far less than ducts fished through finished walls. If there's a choice between routing through conditioned space (better performance) and routing through accessible unconditioned space (cheaper install), discuss the trade-offs with your contractor — sometimes the performance gain justifies the cost, sometimes it doesn't.
Seal and insulate before replacing. If the existing ducts are structurally sound but leaky, a professional seal-and-insulate job at $1,000 to $3,000 may recover 80% of the lost efficiency at a third of the cost of replacement. Get a duct leakage test first to quantify the problem.
Get a Manual D design. A properly engineered duct layout uses less material, delivers better airflow, and avoids the oversizing that wastes money. Contractors who size by rule of thumb often install larger ducts than necessary to cover their guesswork — you're paying for that extra material.
Schedule in the off-season. Spring and fall are the slowest periods for HVAC contractors. Booking ductwork in April or October — outside the summer cooling rush and winter heating rush — often gets you 10% to 15% off labor.
Handle drywall and painting separately. HVAC contractors charge a premium for drywall patching because it's not their core trade. Hiring a drywall crew directly for the repairs typically costs 30% to 50% less.
Get three to five quotes. Ductwork bids vary significantly because contractors use different materials, routing strategies, and pricing structures. A $2,000 to $4,000 spread on the same house is common. Make sure every bid specifies material type, insulation R-value, number of supply and return runs, and whether sealing and testing are included.

Frequently Asked Questions

How long does ductwork installation take?

Two to four days for a full residential system. New construction with open framing is faster — often two days. Replacement in a finished home takes three to four days because of the demolition and access work. Adding a few runs to an existing system for a new room or addition is typically a one-day job.

How long does ductwork last?

Sheet metal ducts last 25 to 50+ years. Flex duct and fiberboard last 15 to 25 years. The joints and seals are usually the first to fail — mastic and tape degrade, connections loosen, and hangers sag. Even if the duct material itself is still good, a 20-year-old system likely has enough joint leakage to justify resealing.

Can I install ductwork myself?

Technically yes for simple flex runs in an accessible attic or basement, but it's not recommended for a full system. Proper duct design requires load calculations, sizing, and layout planning that affect the performance of the entire HVAC system. Poor duct installation causes uneven temperatures, excessive noise, high energy bills, and premature equipment failure. Most jurisdictions also require a permit and inspection for new ductwork, which means a licensed contractor has to be involved regardless.

Should I replace ductwork when I replace my HVAC system?

Not always, but you should evaluate it. If the existing ducts are less than 20 years old, in good structural condition, properly sized for the new equipment, and pass a leakage test, sealing and insulating them is usually sufficient. If the ducts are old, damaged, undersized, or routed inefficiently, replacing them alongside the new HVAC system ensures the equipment and distribution are matched for peak performance. Installing a high-efficiency furnace on leaky old ducts is like putting a new engine in a car with flat tires.

What's the difference between supply ducts and return ducts?

Supply ducts carry conditioned air from the air handler to each room — they're the vents you feel air blowing out of. Return ducts pull air from the rooms back to the air handler for reconditioning — they're the larger grilles usually located in hallways and central areas. A balanced system has enough return capacity to handle the volume of air being supplied. An undersized return system creates negative pressure in the house, which pulls unconditioned air in through gaps, cracks, and leaks. Most homes have far fewer return ducts than supply ducts, and adding return capacity is one of the most cost-effective duct improvements you can make.

Do I need to clean new ductwork?

Not immediately — new ducts should be clean from installation. However, construction dust, drywall particles, and debris from the install can settle inside during the process. Running the system with a fresh filter for a few days after installation captures most of it. A professional air duct cleaning is a good idea 6 to 12 months after a major renovation to clear anything that accumulated during the work.

Is ductwork covered by homeowner's insurance?

Only if the damage was caused by a covered peril — a fire, a falling tree, water damage from a burst pipe. Normal wear and tear, deterioration, and age-related failure are maintenance items and aren't covered. If a storm or other insured event damaged your ductwork and the surrounding structure, the duct replacement would be part of the overall damage claim alongside water damage repair or fire damage restoration.

What's the Average Cost to Install New Ductwork?

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