What does the term "built-in" refer to in construction?

The term "built-in" in construction primarily refers to inherent features of the structure that are integrated into the design and cannot be easily removed or relocated. These features typically include elements like cabinetry, bookcases, appliances, and fixtures that are designed specifically to fit within the walls of a building, contributing to a seamless and cohesive look.

This contrasts with movable furniture pieces, which are not fixed and can be rearranged or replaced based on the needs of the occupant. Heating and cooling systems, while critical components of a building's infrastructure, do not encompass the full range of architectural features that the term "built-in" implies, which emphasizes custom and permanent elements of design. External architecture styles are related to the aesthetic of the building's exterior, rather than the integrated features within the structure itself. Therefore, the understanding of "built-in" centers on the permanent characteristics that add functionality and aesthetic value to the space.