What is the purpose of a "key plan" in construction drawings?

A key plan serves a critical function in construction drawings by illustrating the spatial relationship and layout of various areas within a project. It provides a simplified overview that helps viewers quickly understand how different sections connect and their relative sizes and locations. This is especially important in larger projects, where detailed plans for specific sections might be difficult to comprehend without a broader context. The key plan effectively acts as a reference point, making it easier to navigate through the more detailed architectural or engineering drawings that follow.

In contrast, the other options focus on specific aspects of a project that are not the primary purpose of a key plan. For example, while electrical layouts and timeline summaries are important elements of construction documentation, they do not fulfill the synthesis of spatial relationships that a key plan provides. Similarly, aesthetic design details, while crucial to the visual appeal of a project, are not relevant to the functional aim of a key plan, which is rooted in providing an overall understanding of the layout and interconnectivity of spaces.