an attempt to uncover the truth about September 11th 2001

M.I.T., Rotch Visual Collections

3.0 The Building

Initial design and construction efforts do not require the detailed completion of an office floor. Rather, spaces are only completed when tenancy is established. To assess the marketability of the building, studies are carried out to examine potential tenant improvements. One such study, for a floor occupied by one tenant, is shown in Figure 3.1. In support of office space in a highrise tower there must also be a core area. The core is a multi-use space, containing vertical transportation, washrooms and mechanical, electrical and plumbing systems.

While the prime purpose in developing an office tower is the creation of rentable office space, many other spaces must be created. These spaces are generally intended to directly support the office space or to help the building blend into the urban fabric associated with the site. The most noticeable of the spaces achieving this latter objective is the plaza.

The tower portion of Sixty State Street is located on the south half of the site (see Figure 3.2). The northern half of the site becomes a plaza fronting on the tree-filled Dock Square and Faneuil Hall. Preserved along the east edge of Sixty State Street is a pedestrian walkway, a vestige of alleyways past, that connects State Street with the Plaza. Sixty State can be entered from either State Street or from the Plaza. This entrance level contains a bank and additional space for commercial use. The elevator lobby on the entrance level provides access to both the office tower above and the parking areas below. These below grade parking areas cover the entire site and have space for 240 cars (see Figure 3.3).

Two elevator groups provide access to the office spaces in the tower (see Figure 3.4). A low rise elevator group containing seven cabs, services floors 2 through 17. A highrise elevator group containing eight cabs services floors 18 through 33. The tower floors 34 through 38 are serviced by a separate tower elevator, starting at a sky-lobby on the 33rd floor. In addition to the regular passenger elevators, there is also a parking garage elevator that goes between the entrance level and the 3 garage levels and a service elevator connecting all floors within the structure. Along with elevators, two enclosed stairwells ascend the entire height of the building. These stairwells are primarily intended for emergency egress. Space is required for the central equipment associated with the mechanical, electrical and plumbing system. These spaces exist on parking level and on the 38th and 39th floors. These spaces are connected to typical office floor areas by vertical risers and shafts.

In converting the spaces of a building into a viable physical environment, four major tasks must be addressed: the space must be supported and protected; the space must be accessible; the environment within the space must be tempered; and the space must be made safe for occupancy. Each of these tasks requires the design and coordination of several physical systems.

The space in the building is supported by a structural system. The structural system carries the loads downward through a foundation system where they are transfered to the earth. Once the spaces are supported they are protected from the external environment by an enclosure system, or envelope. The access to these spaces is provided by a vertical transportation system.

Once the spaces have been supported, enclosed and accessed, it becomes necessary to temper the interior environment and provide necessary public facilities. The tempering of the interior climate is carried out by the building's mechanical systems.

Artificial light and other power requirements must be met by an electrical system. Plumbing systems supply the needs of washrooms, allow for cleaning, and facilitate general drainage. Life safety systems must be provided to protect occupants from fire and other dangers. The life safety systems require detection, alarm, suppression and life support components.

While the above mentioned systems are all equally important in providing habitable and useable office space, all are not of equal cost. Figure 3.5 presents a relative cost breakdown for Sixty State Street. The majority of the items in the figure are self explanatory, however, some require more explanation.

General conditions refers to the overhead of running the construction project, for example, electrical power, hoists and supervisory personnel. General items, on the other hand, refers to miscellaneous items not easily classifiable into the other systems; for example, finishing of the plaza and entrance canopies. Tenant finishes are those items provided for in standard lease arrangements for developing interior spaces; for example, partitions, doors and suspended ceilings.

There are also buried costs in certain of the major system costs. Overhead lighting is considered part of the electrical system. In general, life safety systems, with the exception of the sprinkler system, are part of other cost categories: fireproofing is part of structure, smoke exhaust and vertical shaft pressurization are part of HVAC and detection and alarm systems are part of electrical.

The remainder of this chapter will briefly describe the physical systems indicated in italics in the previous paragraphs, with the exception of vertical transportation, which has already been discussed.

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