Conceptual or Schematic Design
Conceptual or schematic design is the first design stage, where the client brief and site analysis are translated into broad spatial arrangements, built form and an organising idea, before detail is resolved.
This stage answers the big questions: where the building sits on the site, how it is oriented to sun and view, how the rooms relate to each other, how many levels, and what the building wants to be. It is deliberately loose. Drawings are typically sketch plans, simple sections and massing studies rather than dimensioned documentation.
The purpose is to test options cheaply. Moving a wall at concept stage costs a pencil line; moving it during construction costs a variation. Most of a project's long-term value, and most of its cost, is locked in by the decisions made here.
In a typical residential program, concept or schematic design is followed by design development, then construction documentation, then the approval pathway. A concept is not a document you can build or lodge from, but it is the thing that everything else is measured against.