Ai3lila Asmh Sfl J!
Total Page:16
File Type:pdf, Size:1020Kb
Ai3 lilA M8N t asmH IJJMSF1 Sfl uoiiuieii J!SPUPXSIV atij 11 -I The Alexander Hamilton Custorii House in New York City he Alexander Hamilton U.S. Custom House was designed bythe prolific architect, Cass Gilbert, and constructed between 1900 and 1907. It is a monumental public building located at the southern tip of Manhattan, directly adjacent to the New York Harbor. It was designed in the Beaux-Arts style with façades clad in gray granite and limestone, a red slate roof, and embellishments, including a sculpture series entitled the “Four Continents” by Daniel Chester French (photo 1). L1— APPIICATOA 38.5 FA[[ 2014 /. The architectural and artistic New York branch containing research Guastavino tile. The curved interior accomplishments merited the building rooms and archives, and the U.S. rotunda ceiling, adjacent to its laylight, being listed on the National Register of Bankruptcy Court for the Southern is decorated with murals depicting Historic Places in 1972 and it became District of New York. ships entering New York harbor by a National Historic Landmark in 1976. the Works Progress Administration- In 1979, New York City’s Landmarks The plan of the building is trapezoidal sponsored artist, Reginald Marsh. Preservation Commission designated with the east and west elevations The murals are executed in the Social the exterior and interior public spaces tapering to the streets of Lower Realism style and are an interesting a city landmark. The building is Manhattan and Bowling Green Park to juxtaposition to the building’s Beaux- the managed by the U.S. General Services north. In the center of the trapezoid Arts style. Above the laylight is an is a central, oval rotunda with Administration (GSA) and houses corridors interstitial space for an. access walkway, that connect many diverse tenants, including the the main building block mechanical equipment (including a Smithsonian’s National Museum of (photos 2 and 3). The interior of the smoke-purge system), and a sloped the American Indian, the U.S. National rotunda is 135 feet by 85 feet by 40 aluminum-framed skylight above. Archives and Records Administration’s feet in height and is constructed using The interstitial space includes steel L1— APPUCATDB 36.5 FAIL 21114 Cordless Multi-Component rafters supporting the skylight and a a person to transition from the ladder perimeter tension ring. The exterior into a narrow built-in gutter. The f sidewalls of the rotunda are clad in skylight and adjacent sloped roofs had copper with decorative brackets, a suffered from deferred maintenance projecting cornice, and fish-shaped due to a lack of safe access. As such, spouts for the removal of precipitation there were several persistent leaks that - Accessories from the built-in gutter. This beautiful had reached the decorative interiors Expect the Best. roof assembly is not visible from the below. Ask your distributor for Albion. public streets, only from the interior- Professional dispensing tools The New York architectural and facing windows and adjacent high-rise since 1929. Request buildings. Before this project, if access engineering firm of Wank Adams our new 88 page Slavin Associates LLP (WASA/ was required to the rotunda-skylight AI.BION Engineering Co. roof, an extension ladder was placed Studio A) was issued a task order 1250 N, Church Street ;4IbioA Mooeestown, NJ 08057-1102 under term contract DISPENSING SOLUTIONS on the barrel roof and against the their to design 856-235-6688 FAX: 800-841-7132 www.albioneng.com E-MAIL: [email protected] dome sidewall. This approach forced a comprehensive rotunda-skylight VJV.SiBION[INF.OR I APPLICATOII —L1 fall-protection system. The GSA’s conjunction with the fall-protection options needed to have the least program for the project called for a consultant/manufacturer, Pro-Bel, visual impact possible, while in no permanently installed personal fall- commenced the project by a visual way compromising life-safety. All of protection system to allow periodic examination of the existing conditions, the proposed design options were inspection, repairs, and maintenance, review of existing and archival reviewed and vetted with the GSA’s including repairs/waterproofing to the drawings, and study of various access Regional Historic Preservation Officer. cladding of the dome; cleaning of roof options. This initial step resulted in drains and gutters; caulking, painting, a design-development report for the The selected scheme provides access glass cleaning and replacement; GSA’s review. Design considerations from an adjacent third-floor low-slope changing of lamps at light fixtures, and outlined in the report included: 1) life- roof with an existing metal guard rail, replacement of filters for mechanical safety and compliance with applicable across a barrel-shaped roof and around equipment. The program also required codes, 2) how to best obtain access a rectangular vent at the mid-point two workers being in the work area for daily maintenance and periodic (photos 4 and 5), into the interstitial simultaneously. maintenance, and 3) the visual effect space, and up from the barrel roof to of the new system against the historic the top of the skylight. The design WASA/Studio A’s Architecture and building fabric. As the building is a included three separate fall-protection Preservation Groups, working in National Historic Landmark, design systems (Drawing 6). The first cable (fl?) 0SECTION: — SOUTH CAALK FALL PROTECTION SYSTEM 11 Drawing 6: Section at south catwalk Liil— AP[ICATIIR 3.5 FALL 214 allows a person to transverse from the flat roof across the barrel roof and either enter the interstitial space or transition up a ladder to the top of the skylight (drawing 8 and photo 9). The second line is vertical and parallel with the ladder and the third is along the skylight in a diamond shape. Fall-protection cables were anchored by means of a post connected to the building’s substructure (photo 10) or to fins welded to the steel frame. Pull tests were performed during the construction phase to ensure code-compliant anchorage to the substructure below the flat roof and copper dome. All users of the fall- protection system wear a full-body harness with two lanyards allowing positive connections at transitions between cables. One of the design challenges was how to connect the fall-protection system to the steel frame below the skylight Drawing 7: and have it pass through the skylight. Section of rotunda ladder The ultimate design called for cutting a slot for a ¾”-metal fin in the skylight 8xx14 ANCHOR CONNECTION PLATE frame at selected locations (photo 11). The fin was then bolted to an upper 3o HOLE (Fr?.) steel receiver located on the top of the CUT SLOT IN EXIST. METAL FARME TO existing steel frame and then connected PASS ANCHOR CONNECTION PLATE (Pr?.) PREPARE & WRAP SUPPORT W/ 2 to a lower welded-steel angle. The two LAYERS OF FLUID—APPLIED FLASHING, EXTEND TILL GLASS; PREPARE, PRIME were then connected with threaded & PAINT — CUSTOM COLOR (TYP.) rods (photo 12). EXIST. GLASS TO REMAIN (TiP.) Another challenge was designing a EXIST. SKiUGHT FRAMING TO REMAN (liP.) ladder from the barrel roof to the top (2x) 5x”xt1 STEEL BRACING PLATE of the skylight. The new custom ladder, (2x) Wo S.S. BOLTS W/ NUTS & platform, and railing assembly had to WASHERS 2’x8x have the smallest footprint possible, 1 STEEL BASE—PLATE EXIST. METAL SUPPORTS TO REMAN and would need to transition over the (riP.) existing built-in gutter. In addition, the EXIST. STRUCTURE & RIVETS TO inner edge of the platform was located REMAIN (TiP.) over the skylight, limiting mounting! support points. For this condition, (4x) %“A X16” S,S. BOLTS W/ NUTS & LOCK WASHERS the ladder itself was designed to be structural, supporting the outer 1 2x8 STEEL BACK—PLATE portion of the platform. The inside edge of the platform was supported by a single steel fin that passed through the skylight frame and attached to Drawing 8: the steel frame below, a more robust Detail of fall-protection anchor version of the skylight fall-protection to rotunda-skylight structure u:i— APPUCATOII 30.5 FALL 2014 Y1[’ I V -—4 L anchor points. To waterproof the contractor provided them with training slotted connection through the skylight, sessions and harnesses. Signage was ladder legs, and cable posts, we used a installed at key points to ensure that PMMA fluid-applied flashing system only authorized building personnel with a reinforcing fleece. A final color used the system. The completed fall- coat of the flashing membrane allowed protection system has allowed the the waterproofing to match the color government’s facility manager, Brooks of the existing aluminum skylight Range Contract Services, to safely and frame and copper-clad roofing, further successfully perform the required minimizing the impact of the new maintenance to the rotunda skylight. elements. About the Author The executed design was competitively Douglas Emilio is an associate partner bid to the GSA’s Northeast and at the architecture and engineering Caribbean Region indefinite-delivery! firm of WASA/Studio A in New York indefinite-quantity general contractors City. He has led complex adaptive- and executed in the summer of 2011 reuse and exterior-envelope projects for by Trio General Contracting of Queens, public and private clients. He is adept N.Y. Construction logistics needed at master-plan development and large- to consider welding in an occupied scale conditions assessments, as well as building directly over public spaces. fine-grained preservation, conservation, Before the building’s maintenance staff and exterior-envelope projects.. could put the fall-protection system into use, the fall-protection installation 35.5 FALL 2014 t141— APPLICATOII.