Schematic design (SD) explores direction. Design development (DD) densifies systems and details. Confusing the two leads to “why isn’t this buildable yet?” frustration.
Schematic design
Options, massing, primary layouts, character, and big budget alignment. Still flexible — by design.
Design development
Materials, structure, MEP coordination beginnings, refined dimensions, and fewer open questions. Changes start to cost more.
Why phases protect you
They create decision gates. Approving SD before DD prevents detailing the wrong concept.
Fee implications
Proposals often allocate fees by phase. Know what approval you are giving at each signature.