BOM costing that rolls up every level
Fintra explodes a bill of materials to raw materials - compounding scrap level by level - and rolls a finished good’s standard cost up from components, labor, and overhead.
Illustrative product view
What a bill of materials is
A bill of materials (BOM) turns a finished good into the components, labor, and overhead needed to make it. Each component line carries a quantity per unit and a scrap percentage; the routing carries standard labor hours and rate plus an overhead rate. A component can itself be a manufactured sub-assembly with its own BOM, so costing has to recurse.
Gross component requirement
required = qty_per × build_qty × (1 + scrap_pct)
For multi-level BOMs, a manufactured component’s requirement becomes the build quantity for its own explosion, and scrap compounds at each level.
Explode and roll up
| Operation | What it answers | Output |
|---|---|---|
| Explode | How many of each component to build N? | Gross requirements to leaf raw materials |
| Cost roll-up | What does one finished unit cost? | Material + labor + overhead = unit cost |
Overhead the way cost accountants apply it
Manufacturing overhead is applied using a predetermined rate on a chosen basis - labor hours, labor cost, or units. The BOM carries that rate and basis so the rolled-up unit cost includes a defensible overhead component, not a plug.
- Overhead basis: labor hours, labor cost, or units produced.
- Standard labor hours per unit and a standard labor rate drive the labor component.
- Cyclic BOMs are detected and rejected so a roll-up can’t loop forever.
Why an accurate BOM cost matters
The rolled-up standard cost is the anchor for everything downstream: it values finished goods on completion, it’s the standard that variances are measured against, and it’s the floor under your pricing. A BOM cost that’s wrong quietly mis-states margin on every unit you sell.
Frequently asked questions
What is BOM costing?
BOM costing rolls a finished good’s cost up from its bill of materials - the components, scrap, standard labor, and applied overhead needed to build one unit. In Fintra the roll-up recurses through multi-level sub-assemblies, so a component that is itself manufactured contributes its own rolled-up cost to the parent.
How does BOM explosion work?
Explosion expands a build quantity into gross component requirements. For a single level, required equals quantity-per times build quantity times one plus the scrap percentage. For multi-level BOMs, a manufactured component’s requirement becomes the build quantity for its own explosion, and scrap compounds at each level down to raw materials.
How is overhead included in the BOM cost?
Overhead is applied with a predetermined rate on a basis of labor hours, labor cost, or units, carried on the BOM. That means the rolled-up unit cost includes material, standard labor (hours times rate), and applied overhead - a full standard cost rather than a materials-only figure.
What is the rolled-up standard cost used for?
It values finished goods when a work order completes, it’s the standard that price, usage, rate, and efficiency variances are measured against, and it informs pricing. Keeping BOM costs current keeps margin analysis and variances trustworthy.
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