World Trade Center, Part 1

On September 11, 2001, I was among the lucky group of people who could, by the end of the day, account for all of my loved ones and their safety.  My husband (boyfriend at the time) was far enough uptown that his office was not touched by the cloud of dust and ash that covered much of lower Manhattan.  His father, a chemist for the Port Authority of NY/NJ, frequently worked in the Towers, and we thought at the time that he was supposed to be there that morning.  (He was on-site for the 1993 bombing.) Fortunately, once the phones lines unjammed and we were able to reach him, we confirmed that he was working at another location, out of harm’s way. There were so very many people who were not as lucky.  Their loved ones names are now memorialized as a part of the nation’s largest man-made waterfall.  But I am getting ahead of myself… Let me begin with the reason for our trip to NYC in the first place.

On Monday, Brianna and I (Monique) were part of a group that traveled from Philadelphia to New York City for a lunch and lecture at the W Hotel on Washington Avenue, overlooking the World Trade Center complex.  Our speaker was Ken Lewis of the architectural firm Skidmore, Owings, and Merrill (SOM), which built the now-completed 7 World Trade Center, and is currently working on 1 World Trade.  Having been on the project since 2001 when excavation began, Ken was incredibly well-versed with the details of not just his own two buildings, but of many of the surrounding buildings being built by other firms as a part of the redeveloped World Trade Center.  Most of the buildings have begun with construction, some of which will continue through 2014. The new complex is intended to be a complete rebuild of all of the original office space, plus enhancements and the memorials, all on the existing site.

Ken shows a rendering of the completed 

skyline with 1 World Trade illuminated.

7 World Trade Center

SOM presented their original plan for 7 World Trade back in 2002, and from the beginning their design focused on transparency – both physically and metaphorically.  The old 7 World Trade blocked the normal street-grid through this part of the city.  Rather than keep the old footprint, SOM proposed a building with a smaller footprint which would allow the gridlines to be reintroduced, maximizing exposure to sunlight and visibility of the rivers on either end of the island. (This also allows for the addition of such much-needed green space across the newly-created street.) With the added sunlight comes decreased energy costs. They’re currently running at 20% below projection: a pretty impressive feat for a building that’s 100% occupied, and was already LEED-certified based on projected energy usage.  (There are no “corner offices”. Any enclosed office space is next to the building’s core, allowing tenants to take advantage of as much natural light as possible.) Custom low-iron glass was used for all windows to maximize clarity.

The architects took special care to learn from the safety issues present in the Twin Towers.  The old buildings were attacked twice: first in 1993 when a car bomb was detonated in the underground parking garage, and again on 9/11. With the new building, precautions were taken to ensure that there were protections against the level of bomb that was used in ’93.

• According to Ken, standard concrete for this type of project is poured at 5,000 psi. The concrete in the lobby of 7 World Trade is 12,000, essentially giving it the capabilities of a blast wall.
• Cameras throughout the ground level with facial recognition software
• Emergency controls for the entire building built in to the main desk, allowing first responders to manage the site from a central location
• Wider stair treads (72” across as opposed to the 66” width in the previous building) give better access to fire personnel, who carry considerably more gear now than their counterparts did when the old 7 was built. This also allows for better traffic patterns by civilians being evacuated.
• Fresh air intakes and emergency generators located at the top of the building
• Pressurized air in the stairwells doesn’t allow as much smoke to fill the space in the event of a fire as a standard stairwell would
• Exit signs and photo-luminescent tape are placed near the bottom of the walls, rather than the top.  If people need to crawl to keep themselves below smoke-level, now they can clearly see where their exit pathways are.

There are, of course, a few features added with aesthetics in mind.  Those low-iron windows I mentioned?  They’re also considerably thicker than standard glass, making the surface as flat as possible in order to reflect an image of the sky throughout the day. There are lights embedded into the exterior walls, which are linked to motion sensors inside the building. At night, as a person moves through the sensory fields, their motion will be reflected by the changing colors of the lights outside.

1 World Trade Center

 Tower 1 is built with specific “memory elements” to honor the Twin Towers. The footprint and the height of the main structure are identical to the originals (although the added spire will bring the total height to 1,776 ft).

Tower 1 (left), and Tower 7 (right)

Sunlight is again a main focus here. The building’s shape begins as a square at ground level, then twists and tapers to an octagon, then to a narrower square at the top.  This structure allows for a maximum of 30 feet from any occupant to a window.  All structural columns are kept to the exterior perimeter, with open floor plans throughout.  There are multiple lobbies in the building: one at below-grade subway-entrance level, which is the expected entrance route of the majority of the foot traffic; and one “sky lobby” near the top of the building. Windows are 13’4” in height, and ceilings are stepped upwards towards the windows, to let the greatest amount of sunlight enter the space.

1 World Trade also has added safety features. In the event of an emergency, one of the elevator shafts becomes a firemen’s lift.  It includes a dedicated stairwell, and the shaft itself is water-resistant and isolated from the other three shafts.  The concrete at the base of this building will be poured to 15,000 psi, triple the standard for this type of application.

Ken mentioned one of his favorite memories of the Twin Towers: the way the edges of the building gleamed golden in the sunset.  That was his contribution to the memory elements of this building.  In the photo above, notice how the vertical edges of the building are sheathed in metal, which is designed to bring that golden glow to the new structure as the sun hits it.

The preliminary construction you see at left will become the Vehicle Security Center.  All vehicles entering the complex will be routed through this centralized hub, which will feature full, border-entry level of security checks.  

Below is a rendering of the Transportation Hub, which has been dubbed the “birdcage” or “phoenix”, and will contain subway access to the complex. The roof’s retractable panels are designed to accommodate the angle of the light that hits it precisely at the time of day that the second plane hit the Towers.