What is the Basis of Design (BOD) and how does it relate to the OPR?

• A. BOD translates the OPR into design criteria, equipment choices, performance requirements, and control strategies.
• B. BOD is the owner's budget document; unrelated.
• C. BOD is a test plan for FPT.
• D. BOD is the regulatory code compliance list.

Answer: (A)

The Basis of Design is the concrete bridge between what the owner wants and how the project will be built. The Owner’s Project Requirements state the owner’s goals, performance expectations, space needs, and constraints. The Basis of Design takes those goals and translates them into specific design criteria, equipment choices, performance targets, and control strategies that engineers will use to develop the system and determine how it will operate.

In practice, the BOD lays out the technical path to meet the OPR: it defines design parameters, such as system types, equipment options, energy and performance targets, allowable operating ranges, sequences of operation, and the controls strategy. It also documents assumptions, codes and standards to apply, and the sources of data used to justify the design. Because the BOD connects the owner’s goals to the actual design decisions, it becomes a key reference during design reviews and for commissioning, helping verify that the final project delivers the owner’s stated requirements.

This is not just an owner budget document, a test plan, or a regulatory compliance list, but the design team's roadmap for turning the OPR into a buildable, testable, and operable system.