Which document type defines the expectations for the functionality of a final design?

The functional requirement document is pivotal in the design process as it explicitly outlines the expectations for the functionality of a final design. This document serves as a comprehensive guide, detailing what the end product should achieve, including performance criteria, usability, and interface requirements. It ensures that all stakeholders have a mutual understanding of the intended outcomes and that the design team focuses on meeting these specific needs throughout the design and construction phases.

This document becomes a critical reference point during the design phases, allowing architects, engineers, and project managers to align their efforts and make informed decisions. Its clarity can significantly influence the success of the project by reducing the likelihood of misunderstandings and misalignments regarding goals and functionalities.

In contrast, design development documents typically provide architectural details and technical drawings but do not specifically outline functional expectations. Technical specification documents detail materials and installation methods but focus more on how things should be built rather than what they need to accomplish. Design review documents may assess designs against established criteria but do not define the functionalities required for the final product. Thus, the functional requirement document stands out as the definitive source for establishing and understanding the functionality needed in the design.