How do you calculate rework cost on an assembly line?

Multiply defective units by average rework cost, add a throughput-loss penalty (rework cost times the loss factor), then add fixed quality overhead. For 12 beds at $35 each, a 30% loss factor, and $200 overhead, the calculator totals $326, about $27.17 per defective unit.

What is the throughput loss factor?

It is the share of additional cost that comes from lost production capacity while line time goes to rework instead of good beds. A 30% factor means rework drags an extra 30% of its direct cost in forgone output — here $126 on top of the direct rework.

What is a good rework rate for mattress assembly?

World-class soft-goods assembly runs first-pass yield above 97-98%, so under 2-3% of beds need rework. If 12 units out of a few hundred fail in a shift, you are roughly in range, but the cost still justifies root-cause work.

How much does a reworked mattress really cost?

More than the repair labor. In the worked example each defective bed nominally costs $35 to fix but $27.17 in fully-loaded terms once throughput loss and overhead are spread — and that excludes any unit that ships defective and comes back as a warranty claim.

Rework cost vs scrap cost — which is worse?

Rework keeps the material but consumes labor and capacity; scrap loses the whole unit's material and value. For a foam bed with expensive cores, scrap usually costs more per unit, but high rework volume can quietly exceed scrap by tying up the line.

How do I lower defect/rework cost?

Attack the dominant defect mode first — usually cover-seam or quilt quality — with better fixtures, operator training, or incoming foam inspection. Reducing the defective-unit count moves the total faster than trimming the per-unit rework cost.

Mattress, Bedding & Foam Product Assembly calculator

Defect/Rework Cost Calculator

Defect/rework cost is the full burden of fixing mattresses that fail inspection — the hands-on labor and materials to rework them, plus the production capacity you forfeit while doing it. Quality engineers and assembly line leads use it to put a dollar figure on cover-seam failures, foam-layer misalignment, and quilt defects that send a bed back for repair instead of out the door. It matters because the obvious cost (the rework labor) is only part of the hit; every reworked bed also steals takt time from good production, and a fixed quality overhead sits on top regardless. Quantifying all three lets you compare the cost of defects against the cost of preventing them.

What this calculator does

Calculate the total cost of mattress defects and rework including labor to repair, replacement materials, and lost throughput during the rework cycle.
Use this when quantifying the cost of quality issues for management reviews, justifying investment in inspection stations, or tracking the impact of specific defect types (tape edge failures, stains, foam tears).
It sums direct rework cost, an added throughput-loss penalty, and fixed quality overhead into a total cost of poor quality for the batch.

Formula used

Direct rework cost = defective units × average rework cost per unit
Throughput loss cost = direct rework cost × (throughput loss factor ÷ 100)
Total quality cost = direct rework cost + throughput loss cost + fixed quality overhead

Inputs explained

Defective units requiring rework:
Average rework cost per unit:
Throughput loss factor:
Fixed quality overhead:

How to use the result

Use it after a shift or audit to size the cost of a defect category, or to justify a fixture, training, or inspection investment.
It does not capture downstream costs of defects that escape — warranty claims, returns, or brand damage — so it understates the true cost of quality.

Current U.S. benchmarks

The producer price index for plastic resins and materials stands at 319.371 (BLS, May 2026), up 19.5% from a year earlier. Quotes priced off last quarter's material cost miss this move.
Manufacturing hourly earnings average $30.27 (BLS, Jun 2026), up 4.4% from a year earlier. Median machinist pay is $28.24/hr (OEWS 2025), with state medians on each state page. Manufacturers have 529k open positions nationally (BLS JOLTS).

Common questions

How do you calculate rework cost on an assembly line? Multiply defective units by average rework cost, add a throughput-loss penalty (rework cost times the loss factor), then add fixed quality overhead. For 12 beds at $35 each, a 30% loss factor, and $200 overhead, the calculator totals $326, about $27.17 per defective unit.
What is the throughput loss factor? It is the share of additional cost that comes from lost production capacity while line time goes to rework instead of good beds. A 30% factor means rework drags an extra 30% of its direct cost in forgone output — here $126 on top of the direct rework.
What is a good rework rate for mattress assembly? World-class soft-goods assembly runs first-pass yield above 97-98%, so under 2-3% of beds need rework. If 12 units out of a few hundred fail in a shift, you are roughly in range, but the cost still justifies root-cause work.
How much does a reworked mattress really cost? More than the repair labor. In the worked example each defective bed nominally costs $35 to fix but $27.17 in fully-loaded terms once throughput loss and overhead are spread — and that excludes any unit that ships defective and comes back as a warranty claim.
Rework cost vs scrap cost — which is worse? Rework keeps the material but consumes labor and capacity; scrap loses the whole unit's material and value. For a foam bed with expensive cores, scrap usually costs more per unit, but high rework volume can quietly exceed scrap by tying up the line.

Last reviewed 2026-05-12.