Design documentation

Design documentation is the project, for as long as the project exists on paper. It is produced by a design institute, an engineering consultancy or an EPC contractor's engineering function, discipline by discipline, and every other party works from it: reviewers examine it, estimators measure it, authorities permit against it, and contractors build from it.

Its structure is staged, and the stages differ by jurisdiction: schematic, design development and construction documents in North American practice; work stages in UK practice; the design-documentation and working-documentation split in CIS systems. Each stage has its own required content and its own consumers, and a document set that satisfies one jurisdiction's stage definition can fail another's on structure alone.

The chronic weakness of design documentation is not any single document but coherence across the set. A project's definition is scattered across hundreds or thousands of files produced by different disciplines at different times, and the interfaces between them — a load on one drawing, the foundation for it on another, the specification for both in a third — are exactly where inconsistencies collect and where reviews concentrate.