Division 13 Special Construction addresses structures designed for a very specific end-use, such as a greenhouse, which require detailed construction specifications and methods tailored to that unique building function.  It also includes the installation of similarly specified and particular sub-systems, such as a bank vault, within conventionally constructed buildings.  Division 13 construction projects tend to require professional insight and construction expertise, making them more expensive to design and build than standard projects.   Division 13 structures and systems often offer less flexibility for future space re-utilization because of the unique nature of their original design intent.