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Lou Blaiotta on Monday, November 13, 2017 at 12:00:00 am
We had a history lesson about transoms, and now it’s time to explain how we achieved the innovative design used for oversized lobby entrances like those Columbia Elevator Products supplied at WTC3, 10 Hudson Yards, and 35 Hudson Yards.
To achieve the outsized flush look in the lobby, Columbia’s solution was to overlap a 10-foot door behind a 12-foot transom. With 2 extra feet of transom extending down over the door, the desired appearance of a 12-foot transom and an 8-foot door is achieved. As in all flush transom arrangements, the bottom part of the door was made thicker than the top, allowing the top of the door to "overlap" the transom, with the bottom of the door extending out enough to be flush with the face of the transom.
Another revolution in the design of these new entrances, with dramatic effect, was to equip them with top-to-bottom LED light fixtures within the depth or “throat” of the jamb which glow when the car arrives at the lobby. The challenge was that the architect did not want to see any of the elevator jamb. In modern masonry applications, it is common to have marble or steel plates extending directly up to the edge of the doors without any of the entrance frame in sight; but, in this situation – because the architect wanted a full 48” opening, and the maximum allowable opening width of the door frame was 48” – placing two 2-in lighting units in the left and right throats of the openings would make the opening 4” smaller.
Here, our solution was to design an unusual jamb profile, with a pocket in the entrance jambs to allow the insertion of the lights in a way that didn’t physically attach to our entrances at all because, if we made a mechanical connection to our frame, it would have violated the UL label. Instead, the frame was pocketed to allow installation of light fixtures in front of, but not touching, our frame. The trim of our jamb was made of the same material as the light fixture itself, creating the illusion that you’re looking at the frame of the light fixture, when in reality a piece of the light fixture trim is actually the elevator entrance jamb (a very skinny profile), and the rest of what you see is the light fixture itself. They’re so close together and perfectly aligned that the brain interprets it all as one big light fixture. This allowed us to create a masonry entrance with a 48-inch wide opening even though the light fixtures actually required 52 inch of width.
Another example of Columbia’s approach to architectural challenges can be found in a drywall environment just 30 blocks north of the World Trade Center at the Hudson Yards development project. Columbia received another OEM order for 10 Hudson Yards where the architect wanted the appearance of floor-to-ceiling openings in the 17-foot tall lobby, with a center-opening look that appeared as if the doors opened all the way to the top. Most often a transom is one large panel above the doors that open below, but in this case the appearance is of a 17-foot center-opening door from bottom to top.
According to code, fixed/non-operable fire-rated door panels can be used in place of a transom panel to create the illusion of a floor-to-ceiling door system. In actuality, there is one set of lower doors that open and another set of doors above it that do not open. In this situation, to satisfy requirements of the Department of Buildings under New York City code, Columbia engaged a professionally licensed engineer to conduct an analysis of design and construction as the basis for a variance. This resulted in the desired look, featuring 8 foot doors and 9 foot transoms with vertical and horizontal seams between.
Over the years, Columbia also tested and received a certificate for 48-inch wide single-speed doors, a very unusual alternative to the two-panel, center-opening doors commonly used for this width opening. At 35 Hudson Yards, for a job ordered by another major OEM that will be installed later in 2017, the requirement is for a one-panel, single-speed door in an opening 4-ft wide by 9-ft high. Since Columbia had previously successfully tested a 4-ft wide x 10-ft high opening, the doors ordered for this job will not require an oversize certificate, but instead they will simply receive a true, full UL label. In this case, the opening needed to be not only “super-tall” but also “super-wide,” to produce a service car using a single-speed door that, for several specific reasons, was being sought in this application.
Columbia Elevator has truly become a relied upon resource in the elevator industry whenever there’s a need to find solutions for innovative entrance designs. We are invited into the process early and we sit with architects and bidding elevator companies – even before the job is sold. This collaborative approach allows us to explore what’s possible, support the design of something that works in an elevator environment and can be fire-rated, while still fulfilling the architect’s far-reaching aesthetic dreams. For the World Trade Center job, we met with the architects years in advance in the conference rooms at WTC 7. At that time, with their offices overlooking that huge hole in the ground known as Ground Zero, we contemplated not only what could be possible, but also what would be a suitable tribute to and recognition of the past even though the new WTC complex buildings were going to look like nothing ever seen or built before.
I feel extremely proud of the work that every teammate at Columbia is contributing to the manufacture of the tall story jobs in NYC. Plus, we all feel a bit patriotic because the work we’ve done to contribute to the rebuild of the Ground Zero area in both WTC3 and 4. We want to build something meaningful so we don’t ever forget; moreover, Columbia is honored to be part of demonstrating America’s resolve that we are even stronger today!
Lou Blaiotta on Monday, October 30, 2017 at 12:00:00 am
|CEO LJ Blaiotta down at WTC inspecting the job during installation.|
The developments allowing for the 20-foot high entrance look at WTC Tower 3 represent a major leap forward. While U.L. continued to build progressively larger testing chambers, they ‘maxed-out’ at 10- feet, allowing for at most 10-ft opening tests. But, the larger chambers also made it possible to now introduce transoms into the fire test, permitting the use of large transoms, in certain combinations with doors, to achieve dramatic “looks.”
Because the World Trade Center is part of the Port Authority, as opposed to the New York City Department of Buildings which can issue design variances, they have their own rules that follow the ASME code A17.1, requiring UL certification. But without an existing laboratory chamber capable of testing entrance & transoms taller than 10 feet, how did Columbia Elevator earn/receive UL oversize certificates for the 20-foot openings?
Products that are larger than the test chambers can only receive UL certification by following a number of engineering calculations and analyses to create the final procedures must be followed for UL to grant an oversize certificate for such heights (anything over 10 feet). With enough supporting data from previous test results, this “engineering evaluation” is deemed to be the theoretical equivalent of testing the physical product in an actual 20-ft chamber. Columbia, after 50 years of testing numerous door, frame and transom combinations and permutations, ultimately received permission for a 10-ft tall single door panel, 4 feet wide with a 10-ft transom, and, as a result, could build 20-ft openings in the WTC Tower-3 with genuine oversize certificates.
The look of the WTC3 entrances was developed with more than a slight nod to history. The profiles of the 20-foot tall LED entrance insets were envisioned as homage to the iconic profiles of the original “Twin Tower” World Trade Center structures, a touch the designers were seeking to achieve in at least one of the buildings in the new WTC complex of buildings. While these entrances bear some resemblance to those from the original towers, there are significant differences. The original 1973 entrances had 6-foot faux transoms, glued to a fire-rated wall, strictly for appearance. The new entrances for this 21st century WTC building feature true transoms despite their additional height.
There are two types of transoms: projected, where the doors go behind the transom, and flush, where the transom and doors are in the same plane. Projected transoms are the more common choice since they are much easier to build. But, for WTC3, the architect wanted a flush transom, where the doors themselves appear to be 20 ft tall. This ruled out the transom treatment used in the original World Trade Center since that would not allow for the desired look. So, what we did was to cut a 20-foot hole in the wall, refill it with fire rated doors at the bottom and place a flush, fire-rated transom at the top.
While Columbia had certification for 10-ft doors, the cabs could not be that tall since all floors above the lobby had only 8’ openings. To learn how we achieved the outsized flush look in the lobby, I’ll share our innovative approach in my next installment.
Lou Blaiotta on Monday, October 16, 2017 at 6:00:00 am
|20 Foot Lobby Entrances at WTC3|
First a bit of history. Before drywall was used in the construction of multi-story buildings, elevator entrances were designed and built for the then-prevailing masonry construction of openings which only required that the doors, and not the frames, have a fire safety label. In fact, in a masonry application, it is allowable to construct a fire-rated opening with just fire-rated doors and no frame at all, as long the code required door-to-wall gap and overlaps around the doors are maintained.
Nevertheless, frames are often used in masonry environments because of the precision they contribute to the fit of components. When openings are cut into a pre-existing masonry wall, it is very difficult - if not impossible - to achieve perfect alignment between elevator car and hatch-side components. This alignment situation is ameliorated using steel frames, which are installed prior to the wall construction and act to ensure elevator equipment alignment. In such masonry circumstances, only the doors require UL® labeling while masonry “alignment” frames do not. To understand why, it’s easier to think of the jambs more as “concrete forms” rather than fire-rated frames.
A subsequent step forward in fireproof construction came with the invention of drywall, which became highly popular due to its lesser cost and weight, faster speed of installation, and its design flexibility. In a fire-rated shaftway, drywall construction is composed of a 1-inch thick shaft wall liner on the shaft side and two thinner sheets of 5/8-inch drywall on the corridor side, with an air space between. The fact that fire could work its way into that so-called interstitial space required capping the ends between the shaft wall liner and the corridor liners whenever penetrations are cut into a drywall system to gain access to the shaftway.
With frames already in use in masonry environments, elevator entrance designs drifted to using the same frames as interstitial end-caps for drywall openings; however, this led to a new set of challenges. Upon installing a steel frame together with a fire-rated door and subjecting this combination to a fire test, it was found that, without masonry behind to hold the frame in place, the frame would twist and allow the gap between the drywall sheets to open and permit fire to spread from floor to floor. It was determined that, to render these frames workable in a drywall application, modifications needed to be made to the design of the frame, including hooks on the back of the doors and other accommodations. Consequently, to properly regulate fire safety in drywall applications, it became necessary to now obtain U.L. labels for the frames as well as the doors in drywall, contrary to the doors-only requirement that is still acceptable by code for masonry.
The first successful fire tests for drywall door and frame combinations were for very small openings because of the design difficulties these presented. As 7- and 8-foot entrances became standard, architects began striving for taller entrances to achieve the bold new looks they were imagining and needing to create to remain competitive. The bigger the openings became, the more difficult the ability to conduct fire testing.
Demand continued to develop for taller openings, more in the range of 9 to 10 feet, not only for aesthetic reasons, but also to create bigger service cars able to move both people and large objects within a building. If such large entrances had not been previously tested, then they would not qualify for a UL label. For a time, the only UL-labeled alternative to such “oversize” entrances was to go with masonry. It was inevitable that a way needed to be found to create door/entrance combinations for drywall that met UL standards.
To accommodate this industry need, Columbia Elevator sought ways to create progressively larger and larger fire-rated door and frame combinations that would pass the required fire test in all wall types. At first door manufacturers in the elevator industry tested designs for masonry openings and then for drywall. After testing several permutations and combinations, Columbia Elevator developed and are manufacturing revolutionary oversized solutions for both environments. Next time, I will share a specific example of how we resolved oversized issues at a major NYC high rise building.