Core service A multistory area in a tall structure that houses key building services such as elevators and/or serves as the wiring distribution site for services such as electricity, telephone, security, fire protection, communications systems, and plumbing lines. This key area should be well-lit, free of accumulations of waste, and accessible for maintenance work. The term "core" has been used in architecture since at least the 16th century, when it was first applied to the central nave of a church built in Madrid. The word comes from the Latin word meaning "heart," or "center." In buildings over 20 stories high, the service core becomes an important factor in design. The majority of life safety systems must be located here, as well as all major utilities. Additionally, this is where most doormen are stationed to provide security and assist with emergency evacuation procedures. The service core is also where most hotel rooms are located because it is here that you will find the main entrance, front desk, restaurants, bars, lounges, etc. It's a very important element to the overall feel of a building and should not be overlooked during the planning process.