How do you calculate cost per unit for duct fabrication?

Multiply the unit count by material cost per unit and the overhead factor to get total variable cost, add the fixed project allocation, then divide by the number of units. With 80 units at $42 each, a 120% overhead factor, and $600 fixed, total cost is $4,632 and cost per unit is $57.90.

What does the overhead and burden factor of 120% mean?

It means total variable cost is 120% of raw material cost, so the factor scales the $42 material up to capture labor, shop time, and consumables. The captured variable value in the default is $4,032.

What is a good cost per unit for duct sections?

There is no universal target because section size and gauge vary; what matters is that your per-unit cost plus margin beats the market price. In the default, $57.90 per section is your break-even floor — price below it and you lose money.

Why allocate a fixed project cost across units?

One-time charges like engineering, submittals, or custom tooling do not change with quantity, so spreading the $600 across 80 units adds $7.50 to each. On a 10-unit run that same $600 would add $60 per unit, which is why low-volume jobs often price poorly.

Material cost vs fully burdened cost — what is the difference?

Material cost is just the metal and fasteners; fully burdened cost adds labor, shop overhead, and fixed project share. In the default, $42 of material becomes $57.90 fully burdened, a 38% uplift you must recover in your price.

How do I set a sell price from this number?

Take the cost per unit and divide by one minus your target margin. At $57.90 cost and a 30% margin target, sell price is $57.90 ÷ 0.70 ≈ $82.71 per section.

HVAC Ductwork, Air Handling & Mechanical Products calculator

Duct Section or Fitting Cost Per Unit Calculator

Cost per unit is the fully burdened dollar figure to fabricate one duct section once material, shop overhead, and a share of fixed project costs are all loaded in. Estimators and shop owners in mechanical fabrication use it to price quotes, set margins, and decide whether a job is worth taking. The key move is the overhead and burden factor, which scales raw material cost up to cover labor, shop time, consumables, and indirect costs, while the fixed allocation spreads one-time engineering or tooling charges across the run. A clean per-unit number is what lets you bid confidently and know exactly where your break-even sits.

What this calculator does

Estimate cost per duct section, fitting, or air handling unit. Combine material cost per unit, fabrication labor rate, an overhead and burden factor, and fixed project costs to calculate a total and a per-unit cost for quoting and job cost comparison.
Use this when building a quote for ductwork fabrication or AHU supply and you need a defensible cost per section, cost per fitting, or cost per air handling unit that includes material, labor, overhead, and fixed project charges. Compare against your target sell price to check margin before submitting.
It computes the fully loaded cost per duct unit by applying an overhead and burden factor to material cost, adding a fixed project allocation, and dividing across the unit count.

Formula used

Total variable cost = units × material cost per unit × overhead factor
Total cost = variable cost + fixed project cost
Cost per unit = total cost ÷ number of units

Inputs explained

Number of duct sections or units:
Material cost per unit:
Overhead and burden factor:
Fixed project cost allocation:

How to use the result

Use it when quoting a duct order, setting a sell price with target margin, or evaluating whether a low-volume job carries its fixed costs.
The overhead factor is a single multiplier; if labor content varies sharply between simple straight duct and complex fittings, a blended factor will misprice the mix.

Current U.S. benchmarks

Industrial electricity averages 8.66 cents per kWh across the U.S. (EIA, Apr 2026), up 5.5% from a year earlier. Energy-intensive steps carry this directly into unit cost.
U.S. housing starts run at 1,177k per year (Census, May 2026), down 8.7% from a year earlier, the demand driver for building products.

Common questions

How do you calculate cost per unit for duct fabrication? Multiply the unit count by material cost per unit and the overhead factor to get total variable cost, add the fixed project allocation, then divide by the number of units. With 80 units at $42 each, a 120% overhead factor, and $600 fixed, total cost is $4,632 and cost per unit is $57.90.
What does the overhead and burden factor of 120% mean? It means total variable cost is 120% of raw material cost, so the factor scales the $42 material up to capture labor, shop time, and consumables. The captured variable value in the default is $4,032.
What is a good cost per unit for duct sections? There is no universal target because section size and gauge vary; what matters is that your per-unit cost plus margin beats the market price. In the default, $57.90 per section is your break-even floor — price below it and you lose money.
Why allocate a fixed project cost across units? One-time charges like engineering, submittals, or custom tooling do not change with quantity, so spreading the $600 across 80 units adds $7.50 to each. On a 10-unit run that same $600 would add $60 per unit, which is why low-volume jobs often price poorly.
Material cost vs fully burdened cost — what is the difference? Material cost is just the metal and fasteners; fully burdened cost adds labor, shop overhead, and fixed project share. In the default, $42 of material becomes $57.90 fully burdened, a 38% uplift you must recover in your price.

Last reviewed 2026-05-12.