BOM Fundamentals
Status: Foundation draft · Owner: Unassigned · Last reviewed: Not yet reviewed
A bill of materials (BOM) identifies the materials and components required to make a product. In apparel, a useful BOM must also say where a component applies: style, colorway, size, or a specific SKU. BOM management is commonly a PLM capability; the released data may feed ERP purchasing and production planning.
Core distinction
| Record | Main question |
|---|---|
| BOM | What is used, where, and in what quantity? |
| Tech pack | What complete technical information must the factory receive? |
| Routing / operations | How is the product made? |
| Material master | What is this fabric, trim, label, or package? |
| Material requirements plan | How much must be obtained for an order after stock and timing are considered? |
Candidate BOM line fields
| Field | Purpose |
|---|---|
| Component ID and revision | Identify the approved material record |
| Category and placement | Distinguish fabric, trim, label, packaging, and use location |
| Color and size applicability | Identify valid product variants |
| Quantity and unit | Define per-unit usage with an unambiguous measurement basis |
| Consumption basis | Separate estimate, approved marker result, and actual usage |
| Supplier and alternative | Record sourcing choice and permitted substitution |
| Effective state | Indicate draft, approved, or superseded use |
Worked example
For a shirt style, the base BOM might specify main fabric, seven buttons, a brand label, and a bag. A navy colorway can map the base fabric and buttons to navy component variants. Size XL can override fabric consumption while inheriting the same label. This avoids copying the complete style for each combination.
The purchase quantity is not simply the BOM quantity: order mix, available inventory, cut-plan yield, approved allowances, and purchasing units must be applied in the downstream planning calculation. Keep those rules explicit to avoid double-counting waste.
Required behaviors to validate
- A component can be shared across several styles without duplicating its master record.
- A variant can inherit defaults and override only its exceptions.
- A released BOM remains traceable when a component or quantity changes.
- Costing can identify the BOM revision and component prices it used.
- A factory can retrieve the correct release for a particular order.
Follow-on research
Expand variant-aware BOM, consumption and yield, change control, and product costing with real examples and acceptance tests.