- The building is internal-load dominated (especially on the lower trading floors) with a lot of computer equipment and servers on various floors. Higher floors are  less occupied with electronic equipment.

- 1.6 Million sq. ft. of low-e glass used in the curtain wall

- Frit pattern on glass covers approximately 30% of each curtain wall piece, reflecting 60% of light where the full pattern is used. Pattern opens up in middle to permit views out.

- Glazing covers the entire facade. In angled parts of the building the  aluminum storefront holds the glass at the top of the structural space allowing more natural light into the space as shown in the diagram below .

- On floors that receive direct sunlight/have vertical shading, the extra light bounces deeper into the space due to the use of reflective materials.

- Open floor plans and open glazing around each floor allow natural light to penetrate deep into the offices. This lessens the need for artificial lighting, and adds a negligible amount of increased need for air conditioning because the building is internal load dominated (more energy is being used inside the building than is coming into the building via solar radiation or heat transfer).

- Entry features an extended roof plane that helps to keep southern light out of the atrium,

while the theater entrance is inside a covered pedestrian walkway.

- Viracon glass used with frit pattern printed onto the low-e glass with an R-Value (a measure of efficiency in thermal resistance) of 3.84.

- The building’s design has been criticised for its overuse of glazing. While the frit pattern and low-e design of the glass allows for less heat transmition into the building, many believe this much glazing is still excessive, especially for an internal-load dominated building. In practice, however, the building still uses less energy for lighting artificial  and heating than the typical office-buiding.

- Motion sensors on the inside of the building ensure that no artificial light is wasted at night.

Air Circulation

- Uses air entering from the top of the building (where the air is less contaminated by exhaust fumes) filtered through a 95% particulate filter then delivered to each floor via an air handler where this filtered air is cooled by water processed in the cooling plant beneath the building.)

- According to the architects, exhausted air is actually cleaner than intake air because of their design focus on making a friendly office environment.

Power Plant Integration

- Cook + Fox incorporated a power plant into the design of their building with the idea that having some electricity generated on the site would be more efficient than having to transport electricity from New York State power plants. This helps the building achieve its LEED qualification for innovative design.

- During the winter, the wasted heat generated by the plant is used to heat the building and to make hot water.

- Year-round (due to the incredible amount of heat generated by the trading floors), the electricity is used to produce ice and cold water used in cooling the building.

- The building produces most of its ice and cold water at night so that it can be used during the day and the plant doesn’t have to work as hard when the sun is out. This also allows the building to keep from stressing the NYC power grid by overusing during the day.

Floor Air Circulation

- Every story has a dedicated air handler that runs filtered outdoor air into an air handler that uses the cold water generated in the basement to allow every floor to adjust the temperature independent of the others. In other words, as outside air runs past the coils containing cool water, the air is cooled by an individual air unit as if each floor were a separate building in a forced air system.

- Temperature sensors, automatic dampers (as shown in the perimeter supply duct in the second image ) and automatic fans control airflow from the handler into the office spaces.

- Air is delivered in underfloor plenum space – this allows the cold air to rise up to replace warm air entering the return plenum space.  The exception is at the end of the section, near the window. This cold air is forced through whenever the temperature on the perimeter of the building is too high (because of the solar radiation or heat transfer in the summer.) Conversely, warm air enters at the bottom of the glazing to replace cold air in winter months.

- Only the hottest return air is exhausted. Before entering the column taking warm air to the roof, the air enters an air column where it is mixed with cool air from the air handler. Air that makes it past this step then enters a mixing chamber to meet with fresh air and reenter the air handler.  This greatly reduces the amount of cool air that would accidentally be exhausted in a normal building.

- While this system does create a more efficient way of handling air in the building, the main focus is on continuously filtering and refiltering the air to create a very clean office environment.

Water Usage/Delivery

- The entire footprint of the building is used to catch water.

- Captured rainwater, groundwater, water that has condensed as a result of the cooling processes, and wastewater from sinks are used in the toilets and then filtered on site to be used in the building again. Waterless urinals are used to reduce the amount of wastewater produced by the building.

- This system uses about 8 billion less gallons of water per year than a building of comparable size according to Cook + Fox’s LEED factsheet.

Primary Structure (Skeleton)

- The building is a typical steel frame with span dimensions ranging from 50’ (especially in spans from the outermost columns to the nearest inner member) to 17’ (between the outer columns.)

- The steel is made from a minimum of 75% recycled materials.

- Changing form of the building is achieved through a manipulation of the floor plane and the secondary structure. The column grid stays fairly regular throughout the building.

- Some members on the exterior are braced frames (see construction photos on the next page), especially along the bottom floors of the building. These help resist lateral loads.

- In the upper floors of the building, lateral loads are resisted with trussed members in the interior of the building around the elevator cores and fire stairs.

- The skeleton is a very simple structure of columns and beams. The loads on the tertiary structure (the concrete slab) are carried to the secondary structure (the I-beams) which are carried to the primary structure (the vertical I-beams.)

- In a braced frame (like those shown in the construction photograph on the following page), lateral loads are resisted when the standard rectangular form of a beam and column structure is made rigid by cross-bracing. The subsequent triangulated forms are very good at resisting most loads.

Floor Plenum and Construction

- The floors consist of raised plenum space of rigid tiles and short metal columns that allows for increased flexibility in these spaces.

- Those raised plenum spaces rest on top of poured-in-place concrete.

- The construction photo illustrates the steel framing supporting the corrugated metal onto which the concrete was poured and then removed.

Foundation

- The bottom of the building is a basement 70 feet below ground which rests on piers driven to the bedrock below Manhattan. This is typical for most office buildings on the island.

- The depth decreases the height required to rest on the bedrock and allows more room for the mechanical systems and electrical system.

- This deep basement requires thick retaining walls to keep from falling inward.

Cladding/Structural Expression

- The exterior of the building is supported away from the structure of the building. There are clear attempts to hide the structure in the interior of the building and it is impossible to discern the structural system without a section or plan, although the metallic coverings on the columns of the lobby do hint at what sort of material is used to support the building. The only honest structure in the building is the use of columns.