The basis of design, often called BOD, documents the design team’s approach to the owner’s project requirements. Reviewers use it to trace assumptions, criteria and intended system behavior into the drawings, schedules and specifications.
Separate the need from the response
The owner’s requirements describe the intended outcomes and constraints. The design basis explains the team’s response. Keeping those roles clear makes a review question easier to resolve when a brief and drawing differ.
A project can use a narrative, system-specific documents or room information to record its basis. Establish which sources actually govern and who owns each one.
Retain assumptions with the design choice
Record operating conditions, occupancy assumptions, selected systems and the rationale relevant to the review. A system selection without its assumptions can be difficult to assess when the owner later changes the program.
When an assumption changes, identify the affected calculations, schedules and specifications. Updating the narrative alone may leave the receiving design based on an earlier condition.
A published requirement mismatch
The school science building case includes elevator brief and shaft information that needed reconciliation. It shows the useful review relationship: a project requirement and the drawings expected to carry it.
The follow-up is to confirm the intended criteria with their owner and backcheck the affected architecture and structure. The finding does not establish which source should be changed without that decision.
Basis-to-document review worksheet
| Check | Sources | Review question |
|---|---|---|
| Requirement | Owner brief, program or OPR | What accepted need is the design approach responding to? |
| Design approach | Current BOD narrative | Is the chosen response and its rationale documented? |
| Assumptions | Conditions, loads and operating criteria | Are the important assumptions explicit and current? |
| Drawing response | Plans, details and schedules | Where does the issued package express the stated approach? |
| Specification response | Performance and installation clauses | Do the requirements agree with the design basis? |
| Decision history | Approved departure or changed requirement | Who accepted the change and did all sources incorporate it? |
Maintain the decision trail
Keep the original requirement, accepted departure and current design response linked. A reviewer should be able to identify whether the design intentionally changed or failed to carry through an unchanged requirement.
Use the design criteria checklist for a fuller review. It adds applicability, review ownership and closure evidence to the source comparison.
Primary reference and review use
WBDG’s commissioning documents guide explains the relationship between owner requirements and design documentation. Source checked October 13, 2026.
Include the current basis and relevant owner criteria as references in a requirements review. The responsible team interprets the requirement and approves the design response.