This is part 6 of 6
Building services co-ordination
Although much of the Corbin restoration and upgrade focused on structural and architectural elements, integrating modern MEP and IT systems within an irregular constricted structure that was difficult to modify and lacked normal headroom in many areas presented its own set of unique challenges.
The MEP programme in the final Corbin building design included:
• vaults for electrical service disconnect switching (supplied by Con Edison) hung from the new sidewalk structure
• concrete-encased electrical duct banks that drop from basement to sub-basement, then pass through the masonry north wall (Figs 49–50), taking the 13.2kV electrical feeders to transformer vaults on the sixth floor of the Fulton Center
• a new steam service and PRV station (also supplied by Con Edison) for distribution to both Corbin and Fulton Center
• electrical distribution room containing transformers and building electrical panels
• a fully addressable fire alarm system with its panel located in the historic lobby
• the fire command centre, at street level, for both Corbin and the Fulton Center
• local IT and electrical closets on each floor
• mechanical plantrooms with individual air-handling units on each floor
• mechanical plantroom for street-level commercial spaces, located in the east penthouse tower
• combined storm and sanitary drainage for the whole site passing through the Corbin basement
• diesel fuel line supply from sidewalk level, through Corbin, to backup generators on the level 7 roof of the Fulton Center
• all incoming IT infrastructure from street level to the Fulton Center
• the escalator control room, in a sunken area of the sub-basement to gain additional headroom for the control panels
• the escalator motor room at basement level, directly above the sub-basement control room and below the escalator trusses, with a direct drive to the escalators themselves (the large uplift forces generated had to be tied down to new foundations)
• rehabilitated electrical control and motor room for the historic Otis elevators (Fig 51).
Above street level, most of the space was reserved for either commercial or transit use and was of high value, so most of the MEP space was pushed below ground if possible. Even though some two-thirds of the existing basement and sub-basement spaces were allocated to MEP systems, in reality this was only 2000ft2 (185m2) in total, and further divided up by a split-level basement, below-sidewalk vaults, low headroom areas throughout the sub-basement, and the integration of the new escalator wellway into the plan. What was left was a series of tightly constricted rooms divided by large piers of unreinforced load-bearing masonry that could not be removed, and headrooms that varied between 8ft–10ft (2.5m–3m) at best. Fitting a lot of services within such a small space required considerable detailed co-ordination between all disciplines.
Additionally, as the new escalator wellway connected Corbin with a large underground network of tunnels, Arup’s CFD model for smoke control in the connected areas required that, as well as extracting smoke directly from the bottom of the Corbin escalator within the adjacent Dey Street concourses, large volumes of make-up air had to be provided at the top of the wellway in the event of an underground fire.
This required that a fan at the top of the Fulton Center supply more than 15 000ft3/min (425m3/min) through a tortuous route that entered Corbin at basement level through the existing north wall and then split around existing and new structural columns to feed into the escalator wellway from the side (Fig 52). The makeup grills were selected to look antique in finish to match the historic brick walls.
Within the commercial spaces to be restored to their original open-vaulted appearance, the Arup/PACA design typically incorporated the electrical lighting, power and IT conduits within the replacement topping to the Guastavino vaults, or in the dry-lining of the north wall, keeping it out of sight. Lighting is controlled by occupancy sensors to comply with energy conservation codes. In the entrance lobby, the lighting is carefully concealed within the existing decorative ceiling.
Air-conditioning systems were streamlined and minimised, and designed to thread between the existing cast-iron framing and the new concrete lateral stability structure. Heating is provided by low-profile perimeter fin-tubes at each floor, replacing traditional large radiators.
The Corbin restoration has been a striking success, and exemplifies how Arup can bring diverse knowledge, skills, and analysis techniques, with a willingness to be bold and experimental, to a historic renovation. Many engineers perceive existing building and renovation projects to be either limiting or constraining by nature, and while there are certainly a diverse range of existing criteria that need to be fully understood and accounted for in designs, this project shows that they can be a catalyst for creative thinking and innovative design approach rather than an excuse for limited vision.
Also, designers should anticipate the need to continue this responsive dialogue with the building throughout construction, in which they will be greatly helped by the selection of the right contractor and specialist sub-contractors.
Arup’s role as lead consultant helped significantly in fostering a creative collaboration between client, approving authorities, engineer and the several architectural firms that assisted with the overall development. The depth of knowledge from Arup’s structural skills networks, with early and consistent input from the firm’s ATG on the behaviour of materials and the resulting local delivery of international skills and approaches, formed a great benefit for the client.
As for the New York City public, they will be able to enjoy the Corbin Building from late 2014 when the Fulton Center as a whole is completed and opened.
49–50. Conduits for main electrical feeders through the north wall at sub-basement level. 51. Restoration of the Corbin Building main entrance lobby required careful co-ordination of the new lighting design with exposed cast iron ceiling.
51. Restoration of the Corbin Building main entrance lobby required careful co-ordination of the new lighting design with exposed cast iron ceiling.
52. Plan view of new ductwork for make-up air supply to the deep escalator, carefully co-ordinated with tight headroom and plan constraints.
53–54. Inside and out, the restored Corbin Building now bears witness to both the craftsmanship of the original and the care and skill of the restoration.
(1) KOSTURA, Z, et al. The Fulton Center: design of the cable net. The Arup Journal, 48(2), pp74-83, 2/2013.
(4) APPLEBY, J, et al. Fulton Street transit center — foundation design and construction in a dense urban environment. Presented at the 2011 Pan-Am CGS Geotechnical Conference, Toronto, October 2011.
(5) BUCKLEY, I, et al. Cast-iron columns and brackets: an historic and contemporary study. To be presented at APTI (Association for Preservation Technology International) Québec, October 2014.
• American Institute of Architects (AIA) New York State Design Awards: Adaptive Reuse/Historic Preservation: Award of Merit 2013
• American Council of Engineering Companies of New York (ACEC NY): Diamond Award for Engineering Rehabilitation 2014
• American Council of Engineering Companies (ACEC): National Recognition Award 2014
• New York Historic Districts Council Design Awards: Honorable Mention 2014
• AIA New York State, Excelsior Award 2014
• Structural Engineers Association of New York (SEAoNY) Excellence in Engineering Awards 2014: Engineer’s Choice Award
• New York State Society of Professional Engineers (NYSSPE) Central New York Chapter 2014 Project of the Year Award (for the complete Fulton Center).
In addition, the Corbin Building restoration was the main contributing factor in MTA being given a special Stewardship Award in the 2013 New York Landmarks Conservancy Lucy G Moses Preservation Awards, for the “management and care of its many historic properties”.
Ian Buckley is an Associate in the New York office, and was Project Manager and structural design team leader throughout construction for the Corbin restoration.
Craig Covil is a Principal in the New York office, and was Project Director for the Fulton Center and the Corbin restoration.
Ricardo Pittella is a Principal now in the São Paulo office. He was the Structural Engineer of Record for the Corbin restoration while he was based in New York.
Client: MTA Capital Construction Lead consultant and multidisciplinary engineering design: Arup — Joseph Appleby, Leo Argiris, Liam Basilio, John Batchelor, Gillian Blake, Mark Brand, Ian Buckley, Alison Caldwell, Bob Cather, Foram Chaliawala, Ann Chamley, Ho-Yan Cheung, Anthony Cortez, Fiona Cousins, Craig Covil, Casey Curbow, Carmen Danescu, Star Davis, Michael Deutscher, Nicola Dobbs, Jonathan Drescher, Alex Engelman, Adam Friedberg, Bethel Gebre, Tom Grimard, Gregory Hodkinson, David Jacoby, Igor Kitagorsky, Tanya Kokorina, Marina Kremer, Steve Lasser, Deborah Lazarus, Adrian Lee, Hillary Lobo, Andrew Marchesin, Cecy Martinez, Cliff McMillan, Kristina Moores, Mark Nelson, Patty Nordhausen, Elizabeth Perez, Clare Phillips, Ricardo Pittella, Samantha Plourde, Lana Potapova, Marie Reedy, Tom Rice, Robb Risani, Justin Rodriguez, Arkady Rubinstein, Yet Sang, David Sivin, Nick Watkins, Chelsea Zdawczyk Architect: PACA (Page Ayres Cowley Architects) General contractor: Judlau Contracting Specialist sub-contractors: Brisk Waterproofing, Western Facades Group, Boston Valley Terra Cotta Foundations contractor: Skanska Construction.
1, 11–15, 27–28, 40, 48, 54 MTA/Patrick Cashin; 2 Anthony Cortez; 3, 6, 46b New York City Library; Back cover, 4, 17, 19, 22–24, 26, 30, 36, 38, 45, 47, 49–51, 53 Ian Buckley; 5 Boston Public Library; 7 Peter Aaslestad/Frazier Associates; 8 Geoffrey Gross; 9–10, 25 PACA/Carlos Carrera; 16, 29, 37, 39a–c, 42, 52 Nigel Whale; 18, 21 Brisk/James Norberg; 20 Brisk/Mike Radigan; 31–32, Yet Sang and Ho-Yan Cheung; 33–34 Lana Potopova; 35, 43 Joe Appleby; 39d Yet Sang; 41, 44 Skanska Construction; 46a Mark Nelson.
Originally published in the Arup Journal, November 11, 2014. Authors include: Ian Buckley, Craig Covil & Ricardo Pittella.