Record both sides of the conversion
Show the takeoff unit and the unit used for labor, material purchase, or subcontract pricing. Write the conversion factor beside the line and name its source.
Common labels such as lot, assembly, or package need a definition before they can support a calculation. Use the material takeoff example as the related control and keep the record with the estimate revision under review.
Separate yield from waste
Treat theoretical conversion, expected yield, and waste as different inputs. A density converts volume to weight; it does not automatically account for spillage or field loss. Keep project-specific waste assumptions visible so reviewers can adjust them without changing the base conversion.
AACE recommended practices offer general estimating references. The project documents, contractor procedures, and approved estimate remain the controlling basis for the decision.
| Review field | Required record |
|---|---|
| Takeoff | Measured quantity and unit |
| Factor | Value, direction, and source |
| Adjustment | Yield and waste stated separately |
| Purchase | Order unit and final rounding |
Check the result in the purchase unit
Recalculate a sample from drawing quantity to purchase quantity and then back again. Compare the result with supplier packaging, quote units, and sensible project totals.
Review rounding after aggregation because rounding every small line can distort the final order. Use the estimate quantity price reconciliation as the related control and keep the record with the estimate revision under review.
