💰 Total Installed Cost
📏 Cost Per Length Unit
Cost Breakdown
Full Cost Table
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How to Use the Ductwork Cost Calculator
Choose sheet metal, flexible duct, or fiberboard based on the intended application and budget.
Enter the total linear length of ductwork needed and the number of vents it will serve.
Choose open access for new construction, a retrofit in a finished home, or difficult access for tight or obstructed spaces.
Click Calculate Installed Cost to see material cost, labour cost, and total installed cost.
What Drives Ductwork Cost
Ductwork pricing comes down to three main variables: material choice, total run length, and how accessible the installation space is. Material affects both the per-metre cost and the labour rate, since some materials are faster to work with than others. Run length scales cost fairly linearly, with labour adding $35 for each vent connection, while installation complexity can swing the labour portion significantly depending on whether the crew is working in open framing or squeezing through finished walls and ceilings. The run length and vent count themselves should come from a proper design, and ANSI/ACCA Manual D is the recognized standard for residential duct design, with one set of sizing principles that applies to every duct material.
Comparing the Three Common Materials
Sheet metal costs the most per metre and takes the longest to install, at $22 per metre for material and $14 for labour in this calculator, but it offers durability and generally the lowest airflow resistance, making it the standard choice for main trunk lines carrying the bulk of the system's air. Flexible duct is the cheapest and fastest option, at $9 and $8, well suited to shorter branch runs feeding individual vents, especially in tight joist bays or attic spaces where rigid metal would be difficult to route. Fiberboard duct sits in between at $14 and $11, offering built-in insulation value but requiring careful sealing to avoid air leakage over time. Sealing matters more than most buyers expect, since ENERGY STAR estimates that about 20 to 30 percent of the air in a typical duct system is lost to leaks, holes, and poor connections, and it lists tangled or kinked flexible duct among the signs of a poorly performing system.
Why Installation Complexity Matters So Much
New construction with open wall and ceiling framing lets a crew route ductwork quickly with full visual access. A retrofit into an already-finished home often means opening drywall, working around existing framing, and patching afterward, all of which adds labour hours beyond the ductwork itself. Difficult access, such as a cramped crawlspace or an attic with limited headroom, slows the work further and can require additional safety precautions. This calculator applies factors of 1.00, 1.30, and 1.50 to the labour portion, so a 30 metre sheet metal run with 10 vents has $770 of labour in open framing, $1,001 as a retrofit, and $1,155 with difficult access.
Sizing Comes Before Pricing
This calculator assumes the run length and vent count entered already reflect a properly sized duct system for the connected equipment. Undersized ductwork restricts airflow regardless of how well it's installed, which can undercut the performance of an otherwise well-chosen furnace, air conditioner, or heat pump. If the trunk line sizes are not settled yet, the trunk duct sizer is a quick way to check them before locking in a material and a run length here.
Ductwork as Part of a Larger Project
If ductwork replacement is happening alongside new equipment, compare the combined project cost against the HVAC replacement cost calculator, and check the HVAC installation cost calculator for general labour rate context. If the real problem is weak airflow or uneven rooms, the airflow diagnosis calculator can help show whether the ducts are actually the cause before committing to a full replacement.
Frequently Asked Questions
Based on this calculator's pricing, a whole-home replacement of about 120 metres of duct with 20 vents in a finished home comes to roughly $5,700 in sheet metal, $4,300 in fiberboard, and $3,200 in flexible duct. A smaller job of 30 metres with 10 vents in open new construction comes to $1,430 in sheet metal. Homes needing rerouting through finished walls or tight spaces cost more, because the retrofit and difficult-access factors raise labour by 30 and 50 percent. Get a written quote before committing.
Sheet metal ductwork is rigid, more durable, and generally delivers slightly better airflow with less resistance, making it common for main trunk lines. Flexible duct, a coiled wire frame wrapped in insulated plastic, is faster and cheaper to install, at $9 per metre of material here against $22 for sheet metal, especially in tight spaces or for shorter branch runs to individual vents. It develops more airflow resistance if it is kinked, sagging, or longer than needed, which is why duct design standards such as ACCA Manual D account for excess length, sag, and compression, and it can degrade faster over time than metal.
Yes, but sealing and insulation matter more than the base material. ENERGY STAR estimates that in a typical house about 20 to 30 percent of the air moving through the duct system is lost to leaks, holes, and poor connections, which wastes conditioned air in unconditioned spaces like attics or crawlspaces regardless of whether the duct is metal or flexible. Properly insulated and sealed ductwork, verified with a duct leakage test, matters more for efficiency than the material choice alone.
Often yes, if the existing ductwork is properly sized for the new equipment's airflow and is in reasonably good condition without major leaks or damage. Undersized or poorly sealed ductwork can bottleneck even a well-chosen new system, so it's worth having a technician check duct condition and sizing before assuming it can simply be reconnected.