Construction data, not a PDF
A BC3 estimate retains reusable structure: chapters, subchapters, items, units, quantities, text, prices and, when present, resource breakdowns and measurement lines. Applications can validate, recalculate and connect this data to business processes.
What must survive an import
A correct total is not enough. Reliable imports preserve hierarchy and economic meaning.
- Codes, descriptions and units without truncation
- Original chapters, subchapters and order
- Quantities, measurement lines and prices
- Material, labour and plant breakdowns
- Progress data when present
Compatibility works both ways
The official definition requires implementations to cover both input and output. Test the full round trip: import, work, export and reopen in another tool.
How BC3 is organised
Records have distinct roles: ~C defines concepts; ~D describes decompositions and relationships; ~M contains measurements; ~T carries text. ~R is waste decomposition and ~P is parametric description. These are not generic labels for materials or prices. The official specification defines their fields and conditions.
A hierarchy example
Imagine a finishes chapter containing a painting item. The item has a code, unit and price; its relationship to the chapter expresses the quantity. It may include a resource breakdown and measurements by room. Keeping only the description and amount loses part of that structure.