The most fundamental roots for Foster’s design of the HSBC building are found in his own solution for the Willis Faber Dumas (WFD) headquarters of 1975 (see case study #7). Completed four years before the Hong Kong competition began, the WFD building portrays many of the ideas consistent and evolving in Foster’s work. The general notion of pushing technical possibilities to the limit in service to building occupants would be important in this instance. His standards of craft, finish, and detail would also come into play at HSBC, as would his egalitarian ideals concerning the workplace. One of the conceptual underpinnings of WFD is found in Foster’s use of a bank of escalators as a central open space in place of closed elevator cores. This would be an equally important feature in Hong Kong, as would the raised service floor system and integrated ceiling. The challenge would be to apply all these ideas at a much larger scale to a building site in a different culture located halfway around the world.
The Lloyd’s of London headquarters (see case study #24) was undergoing redevelopment on a time line about one year ahead of HSBC’s. The bank actually sent a representative to visit Courtenay Blackmore, the person at Lloyd’s overseeing its new building. Although Lloyd’s new building was one-half the floor area and one-third the height of HKSB, there were important connections. Aside from the High-Tech similarities of the two building strategies, their total redevelopment of sites among existing historical structures offers an interesting parallel. As technical coprecedents, the modularized service towers, permanent service gantries, and prefabricated toilet pods of Lloyd’s are features with the most striking resemblance to those of the new Hong Kong Bank tower.
An integral part of Foster’s strategy for the bank was to utilize the space under the suspended floor of the Level 3 banking hall as an open pedestrian plaza. His early analysis of the site revealed that the existing bank building abruptly terminated a pedestrian axis extending from the Star Ferry up to Statue Square. Opening up the ground level of the bank site would connect this axis with the Battery Path walking route north of the central district and open circulation to civic buildings, the cathedral, and Hong Kong Park.
More to the point of the design strategy, dedicating the ground level to pedestrians raised the code-allowable plot ratio from 15:1 to 18:1. This meant that 3 more square feet of floor space could be provided for each square foot of site area, a 200,000 ft2 or 20 percent increase. Without this extra allowance, the design would simply not meet the bank’s need for future expansion. As the existing bank structures beneath the floating villages would be demolished during Foster’s phased regeneration of the site anyway, the pedestrian plaza was a logical solution to maximizing the use of the site.
Daylight is reflected down onto the plaza from a huge periscope of mirrors positioned on the south exterior at Level 12 and at the top of an interior 170 ft (51.8 m) high
atrium. It is possible to use the periscope in reverse by looking up into the atrium to see a reflected view of the sky mysteriously beaming down from midlevel of a high – rise building. The interior mirror is also fitted with artificial downlighting to illuminate the plaza at night. Originally, Foster developed a complementary translucent glass floor for the plaza. This glass floor was to allow light from the daylit atrium above to flow into the lower-level banking hall in the basement. At night, the pedestrian plaza would glow underfoot from artificial uplighting in the basement. This feature was one of the casualties of cost cutting that occurred during early pricing of the design scheme.
Typhoon screens are hung at both ends of the plaza where it passes under the edge of the building. These can be lowered during storms to reduce the venturi effect produced by the plaza’s low height relative to the air dam effect of the tall building. Flanking the covered area of the
39.4 ft (12 m) high plaza to the west are elevator lobbies opening behind 16 structural columns. Two fire stairs land at the northwest and southwest corners. The east wall is formed behind another row of columns by stairways, service elevator shafts, and mechanical risers. Two escalators carry customers from the plaza through the glass underbelly up to the banking hall. An open-sky plaza is situated on the southern site boundary beyond the footprint of the building. Another escalator runs from the southwest corner of the open plaza up to a banking hall entrance lobby on the west face of the building.
After the bank rejected his multichevron idea, Foster explored several alternatives for delivering his phased redevelopment scheme. He explored the structural possibilities with Arup & Partners: a triple chevron and a staggered organ pipe, to mention a couple. By the autumn of 1980 they arrived at a suspension scheme later termed the “coat hanger.” Pairs of two-story coat hangers would span between steel mast towers and cantilever beyond them. Central spans would carry suspended floors; the cantilevers would contain all the building services.
Detailed information from the wind engineering study was now available and had to be factored in. Amazingly, the steel frame design for the strongest of typhoons gave the building a structural lifetime rated at
10,0 years, so fatigue should never be a factor. The wind study also made it possible to minimize some of the steel needed in the building through refined design calculations. Earthquake loads were considered but did not offer the extreme limiting factors that potential wind loads did. Further economizing might have been possible if time had allowed for negotiation with the Hong Kong building code authorities in regard to exactly how the structure would perform.
The building is carried vertically by eight steel masts arranged in two rows of four. These are the only lifting elements of the building and contain more than one-half of the building’s total structural steel. The masts rise from the lowest basement foundation level, 115.5 ft (34 m) down, to the top of the building frame, 558 ft (170 m) up. Six of the masts are fitted with permanent service cranes. Foundation support is provided by four 9.8 ft (3 m) diameter concrete piers at the base of each mast column, totally independent of the basement structure. Masts are placed in two rows 110.2 ft (33.6 m) apart and spaced in bays of 36.4 ft (11.1 m) between them. Each consists of four tubular steel columns ranging in diameter from 55 in. (1.4 m) at the base of the building to 31.5 in. (0.8 m) at the top of the building. The corresponding steel wall thickness is 4 in. (100 mm) at the base and 1.6 in. (40 mm) at the top. Center-to-center dimensions of the mast columns are
15.8 ft X 16.7 ft (4.8 m X 5.1 m) in plan. Horizontal bracing at 12.8 ft (3.9 m) vertical intervals produces a vieren – deel truss action in both axes of the masts. Diagonal cross bracing across the masts is added in the horizontal plane within each floor slab level.
Two-story-high trusses divide the building into five vertical layers of independently suspended floors. There are 17 pairs of these suspension trusses, spanning 110.2 ft (33.6 m) between the vertical masts and cantilevering
35.4 ft (10.8 m) beyond them. Horizontal truss members are 3.0 ft (900 mm) deep and double as the primary floor beams at the double height levels. Diagonal members are 1.6 ft (500 mm) deep. For aesthetic reasons, the top boom is omitted on trusses exposed to the north and south elevations. Diagonal booms are about 65 ft (20 m) long and attach to gusset plates on the mast columns with pins varying up to 14 in. (350 mm) diameter set into spherical bearings of 0.5 to 2.0 ft (150 to 600 mm). Tubular suspension hangers connect at the center point and end of each two-story truss. There are a total of 102 hangers of about 10 in. (250 mm) diameter to carry the building floors, each hanger being erected in three tapering segments and connected with screwed couplers. All above-grade floor levels are suspended from the hangers, leaving a large column-free area at the ground floor level. Occupied floor space is carried between the rows of masts. Service modules and prefabricated stair units are suspended outside the masts to the east and west orientations and act as cantilevers to balance against occupied floor loads.
North-to-south cross bracing occurs at each of the suspension truss levels across the inner two columns of each mast. In the atrium, from Levels 5 to 8, a larger cross brace is exposed to view from the banking hall.
At the fabrication yards, every piece of the masts had to be built to within 0.08 in. (2 mm) of true. There was also little repetition of elements, because less steel was needed as the structure went higher and proportionally smaller members were used. More than 3400 drawings were needed for steel fabrication and some 700 more for field construction. Full-scale prototypes of the system were tested at the Britannia Works in Middlesborough, England, where they were first subjected to the design building loads and then loaded to destruction. Prefabricated mast sections were delivered to the site as two-story corner assemblies, with connections made onsite at the middle of each horizontal beam.
Floors are built on 15.8 in. (400 mm) secondary beams at 7.9 ft (2.4 m) spacing and act compositely with the 4 in. (100 mm) concrete slab poured on 2.0 in. (54 mm) deep profiled metal deck. These secondary floor beams span 36.4 ft (11.1 m) from north to south and rest on 3.0 ft (900 mm) deep primary beams. In turn, the primary beams span 55.1 ft (16.8 m) between the mast and the central hangers suspended from double height trusses above. The assembly was designed to carry a live load 20 percent greater than code required to ensure flexibility of the interior arrangement and to accommodate advanced office technologies of the future.
Initially, the fire protection and corrosion resistance of the structure was intended to consist of water-filled steel sections with a molecularly bonded stainless steel finish. The offshore oil industry was already using this metal fabrication technology for drilling platforms. In drilling applications however, the stainless finish was inside the steel tubes and a separate asphaltic corrosion-protection material was applied above the platform waterline. Further study showed that the stainless finish could be reversed to the outside of the tube, but this made on-site welding assembly almost impossible. At any rate, the quality of steel used in this process was not adequate for the vertical loads of a 40-story building, so the idea was abandoned. Consequently, corrosion protection, fire protection, and then a finish material would have to be applied in three separate processes. Aluminum was a clear choice for the finish material; it could even be finished to match the aluminum-skinned wall cladding.
Corrosion protection of the steel structure is a cemen – titious barrier coat (CBC). This is a gunite material consisting of three parts sand to one part cement, mixed with aggregate, a polymer, water, and 5 percent by weight of reinforcing of stainless steel fibers. The alkaline content of the cement ensures protection from rust. CBC was applied in two 0.25 in. (6 mm) layers after the steel was sandblasted clean. Because of delays in the delivery of steel, treatment had to be applied on-site rather than at the factory.
This led to considerable problems of quality control and cleanup during construction. Inevitably, it affected nearby work on other phases of the construction.
Application of two-hour fire protection for the steel followed the CBC. Stainless steel mesh was wrapped around the corrosion protection, and strands of the mesh were bent back to secure a thin ceramic blanket. This was followed with a wrapping of reinforced aluminum foil. Not only did the foil protect the ceramic blanket from construction activity damage, it also sealed it from the air space inside the column cladding that was to be used as a return air plenum.
The four basement levels were formed within a 3.1 ft (1.0 m) thick perimeter wall that extends down to bedrock. The perimeter wall was supported by reinforced concrete slab floors poured over a column grid of 23.6 ft X 26.6 ft (7.2 m X 8.1 m). The columns in turn were supported on 6.6 ft (2.0 m) diameter piers. Basement walls were finished with a concrete mixture combining Japanese cement with washed Pearl River sand and Hong Kong aggregate. The mix was poured into Finish beechwood formwork that had been coated with resin for smoothness and consistency.
Aluminum second-skin cladding for the structure was developed with a 6 in. (152 mm) space allowance around the steel members for fire protection and moistureproof – ing. This void is also used for some HVAC return air paths. Detailing of the cladding joints had to be both waterproof and visually thin, and their finish would have to stand up to the hot-humid climate for at least 50 years. The final solution was a 0.2 in. (5 mm) thick aluminum skin with a nine-step fluoropolymer paint finish that is baked onto the metal at 500°F (260°C). Tolerances for installation were on the order of ± 0.125 in. (3 mm).
Cladding for the opaque exterior surfaces was made from honeycomb reinforced aluminum panels. The technology for this material was developed for aircraft and aerospace applications — it is lightweight and strong enough to be used for helicopter rotors. Panels for the bank are 1.0 in. (25 mm) thick and finished with the same silver-gray coating as the structural cladding.
Glazing for the office areas is 0.5 in. (12 mm) thick insulated glass with a silver reflective coating. An outer sheet of 9 mm glass is clear, the inner 5 mm pane is coated. Between them are perforated aluminum blinds sealed in the air space and controlled by recessed levers in the window mullions. Blinds were omitted on the north elevation to preserve the view of Victoria Harbor. The curtain wall uses full-height glass set in a sill resting below slab level so that the glass appears to disappear into the floor. Vertical framing consists of circular hollow-section aluminum mullions at 48 in. (1.2 m) centers. The glass is set against the mullions in structural silicone sealant. An integral perforated web flange on each mullion provides wind bracing. At the double-height level, an external truss at each window mullion braces the glass wall against wind loads. A special condition occurs at the east end of the banking hall atrium from Level 3 to 12. This has been named the “cathedral wall” and consists of widely spaced double glazing with service walkways carried between the two layers.
The glass is shaded by an aluminum sunscreen extending 5.9 ft (1.8 m) beyond the curtain wall. It consists of an inward-louvered grille and an outer set of four louvers, both resting on perforated support brackets. The mounting bracket’s outer edge aligns with the center of the outer mast column. These shades are used on the north side of the building as well as the south, primarily because they also provide a maintenance walkway. Glass panels at each end of the walkway open for access and double as code-required smoke vents. The true solar orientation of the building is about 16 degrees east of north anyway, so the waterfront orientation does receive direct sun until late morning from March through September.
The sunscoop daylighting system is also an element of the envelope. As a periscope, it is composed of two sets of mirrors. On the south exterior of the building, at Level 12, is a bank of 4 in. (100 mm) wide mirrors that track the sun’s altitude angle by moving on a horizontal axis. Movement is very slow to prevent distracting flashes of light to the interior. The assembly is supported on a steel space frame bracketed to the vertical masts. An interior reflector assembly is made of steel tube framework. It covers the top of the atrium space with pure aluminum convex reflectors clipped between the tubes. The tubes also support artificial lighting connected directly to them.
A suspended glass canopy at the floor of Level 3 separates the main bank hall and its atrium from the pedestrian plaza below. The form of the canopy is determined by the catenary contour of draped steel V-sections 10.2 in. (260 mm) deep that hold it in tension, like a rope bridge, across the 69 ft (21 m) span and resist wind uplift. An aluminum framing system acts as a stabilizing compression frame to receive insulated panels of 0.4 in. (10 mm) tempered over 0.5 in. (12 mm) laminated glass construction. The strength of the glazing is sufficient to prevent a 1 kg steel ball, falling from the top of the fourth floor, from penetrating through to the pedestrian plaza below. This strength also allows a cleaning crew to simply walk across the glass floor. The canopy is penetrated by two off-axis escalators carrying customers from the plaza up to the main banking hall.
All the air-conditioning, electrical, and plumbing distribution for the building was pushed to the east and west walls, and services are delivered under a raised floor system. Along with elevators and fire-stairs, the mechanical systems are used as buffers to the undesirable orientation. A heavy mechanical equipment plant and electrical gear are deployed in the basement. This scheme has the intended effect of freeing the occupied floor plates, leaving view and flexibility completely uninterrupted. An automated building control system monitors performance from the 27th floor.
Requirements for phased building occupancy and rapid construction led the designers to opt for a modularized service plant that incorporated primary HVAC distribution, toilets, and storage. These modules are similar to those simultaneously planned for Richard Rogers’s design at Lloyd’s, but the London building’s service pods did not include air-conditioning nor had they gone out to a manufacturer for fabrication yet. At HSBC, the service modules were eventually installed at the rate of two per day, always after midnight when the streets could be cleared for large deliveries and the cargo lifted carefully into place. Structurally, the pods are independent of the main building frame, but they do provide cantilever weight to offset the occupied floor span between the main masts. They were covered in stainless steel skin at the factory and clad on-site with aluminum honeycomb panels. Distribution of service mains from the basement cooling plant to the modules occurs at the corners of the building, through prefabricated two – and three-story-high vertical stacks concealed behind layers of exterior cladding. There are 160 total service modules, weighing between 30 and 55 tons apiece and measuring up to 39.4 ft X 11.8 ft in plan and 12.8 ft high (12.0 m X 3.6 m X 3.9 m).
Delivery of air to the occupants is via air terminal units beneath the floor. A constant volume system feeds conditioned air from the service modules to strip louvers along the window walls where thermal loads are consistent. Variable-air-volume fans supply air from the same source to floor registers distributed throughout the interior. Some 80 percent of return air is taken through the floor plenum. The remaining 20 percent is returned through fluorescent light fixtures to remove the waste heat they generate before it is distributed into the room. This air is drawn through the hollow space behind the mast column cladding and then ducted to the service modules.
Heat collected from the building by the HVAC plant is rejected to a seawater cooling system instead of conventional cooling towers. This saves potable water, mechanical equipment, and the space in which towers are placed. The original 1935 building used the same system by pumping water from the bay 1312 ft (400 m) to the building through two 1.3 ft diameter (400 mm) mains laid in a trench just below Statue Square. Local authorities suggested that an expansion of this system might be allowed if it would also service some of their buildings and surrounding businesses. In December 1981, Foster’s team proposed to excavate a 23 ft (7 m) diameter tunnel 197 ft (60 m) below Statue Square in bedrock granite for a community sized seawater system. The deep setting of the tunnel was dictated by the depth of the decomposed granite soils that would flood continuously with the ocean tides. Drilling deeper in solid granite allowed for faster completion and avoided requirements for primary support. The tunnel depth was also set to avoid the existing Charter Station metro line that extends 115 ft (35 m) below grade.
Six 40 in. (1.0 m) diameter pipes would carry seawater through the tunnel to the new development’s cooling plant; two of them were to provide supply and return for the bank, two of them would be shared with neighboring buildings, and the last two were for back-up in case of repair. A pumping station at the Star Ferry was designed to deliver 1057 gal/sec (4000 l/sec), of which 75 percent was intended for other buildings. After negotiations about shared costs broke down during a brief economic recession, the project was approved out of sheer expediency and implemented in time to allow for an August 1984 completion date. Redesign, after withdrawal of the community partners, resulted in an 18.0 ft (5.5 m) tunnel size and piping in three 28 in. (700 mm) mains.
Electrical service capacity is 21,000 kva, or 21 megavolt amperes, about one-third of which is dedicated to air – conditioning. There are also 6 megawatts of standby generation. More than 3,600 km (11,881,000 ft) of cabling was used in the building.
Vertically, the building is divided into eight zones plus the street level pedestrian plaza. Basements constitute the sublevel Zones 7 and 8. The remaining six layers are organized as vertical blocks divided by double-height sky lobbies in a scheme that has been compared to a stack of five midrise buildings. The number and placement of these divisions are based on interior requirements; they are not structural load distributions. The lowest of the six villages, as Foster calls them, is the double-height main banking hall, which is reached by escalator from the pedestrian plaza. Each of the upper four villages is accessed by elevators stopping only at the double-height spaces of the suspension trusses. The double-height spaces, which become the focus of the interior by their being positioned as reception areas, include the grander spaces. The restricted access they provide to upper floors also ensures security and compartmentalizes the various departments of the bank into discrete areas. Circulation in and among villages is by open escalator rather than by crowded elevators.
• Zone 1 —Level 3/4 is the double-height public banking hall and is accessed by escalator through the glass underbelly of the atrium or by an elevator rising along the west side of the building from Queens Road. There is no suspension truss at this level; the floor is suspended from above. The block of floors extends up through the suspension truss at Level 11 and is united by a central atrium space measuring
36.4 ft X 212.6 ft (11.1 m X 64.8 m). A huge periscope arrangement of mirrors brings daylight from the south facade into the atrium, down its length, and through the glass underbelly to illuminate the pedestrian plaza. Floors above the banking hall in this atrium zone are for the area management department. Floor area is about 176 ft X 213 ft (53.7 m X
64.8 m) overall. Three fire stairs and five mechanical modules serve each level in this zone.
• Zone 2 —Level 11/12 is a suspension truss level. It contains the reception area for office floors 13 through 19. This village houses retail banking and various offices. The double-height level contains offices for senior management. Like all of the suspension truss double-height floors above Level 11, substantial east – and west-facing terraces provide amenity and code-required refuge in the event of fire. Setbacks are chiseled into each zone of the east facade providing a successively smaller profile as dictated by shadow line regulations. The setbacks are not visible on the north or south because of fire stair corridors that complete the elevations on those sides. These floor plates are based on a plan area of roughly 176 ft X 176 ft (53.7 m X 53.7 m). Four fire stairs and four mechanical modules serve each floor in this zone.
• Zone 3 — Level 20/21 is a suspension truss doubleheight space for staff amenities, a conference center, and meeting halls. The floors above, Levels 22 through 27, are dedicated to data processing and related departments. These floor plates measure roughly 176 ft X 176 ft (53.7 m X 53.7 m). Four fire stairs and four mechanical modules serve each floor in this zone.
• Zone 4 — Level 28/29 is another suspension truss level space, this one for bank officers’ dining and recreation facilities. Above it are the floors for the bank’s head offices on Levels 30 through 34. These floor levels are cut back in plan by stepping back one mast bay on the south as well as the progressive chiseling into the east elevation above Level 13. Each floor
is still roughly 176 ft X 176 ft (53.7 m X 53.7 m). Three fire stairs and three mechanical modules serve each floor in this zone.
• Zone 5 — Level 35/36 is the next suspension truss level. The executive dining level is located here. Circulation from this level is more restricted, and it appears to communicate more with the spaces below it than with those above. Levels 37 through 40 actually make the next vertical zone and are dedicated to senior executive boardrooms. The floor plate measures about 123 ft X 123 ft (37.5 m X 37.5 m). Three fire stairs and three mechanical modules serve each floor in this zone.
• Zone 6 — Level 41/42 is the highest suspension truss —this is the chairman’s apartment with two levels above. The floor plate is roughly 70 ft X 118 ft (21.3 m X 36.0 m). Two fire stairs and two mechanical modules serve each floor in this zone. A visitor’s gallery is located on Level 43, separating the chairman’s quarters from a rooftop helicopter landing pad.
In plan, the horizontal organization of the bank reflects a concern for views, solar orientation, and day – lighting, not unlike that of Lockheed Building 157 (see case study #9). The north and south (NNE and SSW solar orientations) facades are fully glazed, and the interior is largely free of internal obstructions. The east and west (ESE and WNW) walls are used for the mechanical and toilet modules as well as for fire stairs. All of the passenger elevators are located on the west wall. Service elevators are located in the foyer of each fire stair. Small refuge areas are located at the suspension truss levels along the west wall between the passenger elevator lobbies, supplementing the primary terraces provided on the east side.
Expansion of the interior floor space was planned in by oversizing the structure to allow for mezzanines to be constructed in the double-height spaces and for all of the shadow setbacks of the building to be in-filled. If code restrictions are ever relaxed to allow these plans to be realized, interior floor space could be increased by as much as 30 percent.
Floor, Ceiling, and Partitions
A 48 in. (1.2 m) grid was established as the planning module of the interior. Honeycomb reinforced aluminum panels, similar to those used to clad the building, were fabricated to cover a 2.0 ft (600 mm) deep raised floor system over most of the building services. At the center of one-quarter of each panel a hole was drilled to provide either air distribution or service connections. By rotating the panel, services can be located at any center location of a 24 in. grid. The panels are covered in carpet in for office areas, with a gray metal trim that accentuates the floor pattern.
The ceiling is suspended from dovetail slots in the metal floor deck. It is made of gypsum plasterboard panels in-filling between the cladding of the primary and secondary floor beams to reveal the structural grid and maintain maximum ceiling heights in between. At the perimeter, outside the main floor beam, the ceiling slopes upward to meet the window head and maximize light and view. Fluorescent ambient light and aimable tungsten-halogen task light fixtures are recessed in the suspended ceiling panels, as are fire detection, sprinkler, and public address systems.
Partitions are custom-made to hang from the ceilings and can be rapidly demounted. Accommodation of floor deflections of up to 2.4 in. (60 mm) and lateral swaying of the building frame led to the provision of slip joints at the floor and at vertical joints. Door frames rest on the floor and slide up and down in their mountings. Metal and glass are the materials of choice, with aluminum mullions and transom. Blank panels are made from galvanized sheet steel with gypsum lining to decrease sound transmission. The doors are heavy steel with recessed hinges.
Occupancy densities for office areas were established at a level between Eastern and Western workplace standards. Workstations were paired to further recognize the cultural preference for working in close quarters. This arrangement also promised the highest flexibility for various layouts. Desks were logically aligned perpendicular to windows for better daylight quality and reduced glare from bright windows. This alignment also prevents anyone from monopolizing the view. After about 150 suppliers were qualified, a Dutch firm was chosen to provide desk systems. This company’s 45 degree linking module seemed to provide the best combinations of possible arrangements. Ergonomic adjustments were made to provide better working conditions for the Asian physique.
Elevator lift cabs are translucent, and the elevators having exterior shafts are transparent. There are 23 high-speed passenger elevators running at 20 ft/sec (6 m/sec) and 5 freight elevators. Distributed through the building are 62 escalators. Prefabricated stair modules fit into the east and west facades in the same way as mechanical service modules do. Stairs are stacked directly outside the structural masts to form complete towers. Stair modules are located at the outside corners of the west elevation and the two inside bays of the east elevation. Mechanical service modules are located in the opposite manner in the other four slots beside the masts.
Basements
The lower banking hall and safety deposit boxes are located in the first basement level, just below the pedestrian plaza. Some parking is also located at this level. Beneath that are three levels of basements for the heavy mechanical systems’ plant and electrical gear.
Integration Highlights
• The organization of the site maximizes the redevelopment strategy and establishes a pedestrian mall between major footpath arteries.
• The high degree of prefabrication meant close tolerances for construction. Although accurate tolerances in factory assembly were usually attained, there were several problems with field assembly allowances for dynamic loading under differing construction loads and some difficulties with materials that relaxed or warped during transit to Hong Kong.
• The distribution of mechanical services to modular pods avoids the necessity of locating mechanical floors at high levels of the building. This preserves the premiums of daylighting and view for occupied floor spaces. It also avoids the necessity of an interior mechanical core that would obstruct the open plan of the bank floors and their flexible use.
• The division of the building into pagoda-like sections corresponds to the interior village organization and structural scheme. It also breaks down the mass of the building into a legible scale. To some extent, this imitates the regional vernacular of stacked spaces frequently found in Hong Kong, whereby restaurants and offices and apartments are successively stacked over street level retail volumes.
• Perimeter air-diffuser strips visually continue the louvers of the external sunscreen. At the upper room level, the outer 9.8 ft (3.0 m) of the ceiling slopes upward to meet the bottom of the sunscreen bracket where it meets the 24 in. (600 mm) deep air diffuser plenum.
• Sunscreens double as maintenance walkways and are also designed to allow views down to the street. This trio of performances is accomplished without adding a significant structural load at the outside edge of the curtain wall. As a bonus, they are used to decorate the building for seasonal celebrations, saving untold weeks of constructing bamboo scaffolding.
• The high-speed elevator and connecting escalator circulation scheme reduces travel time and manages security. As in the trading room of the Lloyd’s building, this has the effect of creating an interconnected single-floor space.
• Open floor planning yields 75 percent useful floor area, versus the usual 60 to 65 percent found in office towers.
• The air space between the aluminum cladding over mast columns and the fireproofing is used as a return air plenum.
This bank is nothing less than a new prototype, an example of how to design and construct a building. Nothing about the design of HSBC was taken as a given of standard practice. None of its components were chosen from a catalog. Given the client’s mandate to deliver “the best bank in the world" Foster did not set out to select the best available components, but to custom-design every piece of it. The result is a crowning masterwork of High Tech design, which hints about where the evolution of High Tech is leading, what the next step might be.
It is worrisome in some regard that it took a billion – dollar bank building on a half-billion-dollar site to realize this advanced project, but perhaps that is the cost of such an invention. The fact that there are so few components or construction techniques to take from here and apply to other designs may also seem to be a failure of sorts, but new products, however well designed, are not the greatest contribution of this building. Instead, the foremost advance made by the architecture of the Hong Kong and Shanghai Bank is the method used to develop its design and realize its construction. The many successes of its built form not withstanding, HSBC is a lesson in how commodification of technology can lead the practice of architecture, even more than it is the exemplary result of a singular project.
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Figure 10.31 View of the Hong Kong and Shanghai Bank and the Hong Kong skyline from the bay. (Photograph courtesy of David Chan.) |
Foster’s strategy involved manufacturing and fabrication specialists in the design process. Commonplace adoption of this approach would require ongoing two-way communication between designer and product supplier. Ideally, it would also lead to interactive discussions between all of the design and building team members as decisions made in one area affected others. Communication would pool the expertise of architectural
generalists and commercial specialists. Idealism, practicality, and coordination would be optimized.
Realization of this strategy at HSBC was less than perfect, of course; there were many failings and cultural differences to sort out along the way. In the more stressful moments, Foster’s office and the rest of the building team even joked about moving to Paraguay. Many of the discussions were heated and contentious, both between the design team and the suppliers as well as with the client. The project was large enough, however, to attract the attention of product fabricators around the world, and that helped to ensure its success. There was a sufficient amount of business in this one building to allow for the use of new technologies and the design, testing, and refinement of new products. It hardly mattered whether none of the products would ever be sold again.
Foster has always demonstrated an inclination toward industrial design in his architecture. The suspended glass curtain wall at the Willis Faber Dumas headquarters (see case study #7) is a good example. This component was developed in his office for one project; Foster traded the design rights to Pilkington Glass in exchange for the product liability of the curtain wall’s performance on the project. In Hong Kong, Foster began by deciding that every product in the building would be designed along the same lines of customization. This is the kind of exploration and refinement process that modernists like Eero Saarinen have been leading toward for a long time (see case studies #6 and #10).
The ultimate goal of this process dates back to the Bauhaus ideal of industrial production. The new term for this goal is even more ambitious: mass customization—the one-off manufacture of components specifically designed for a single application, achieved at economies made possible by design simulation, virtual performance modeling, and automated precision manufacturing, and able to adapt to subtle variations in production for differing conditions.
At HSBC the elements of this process are all in place. The list of innovative procedures engaged is far removed from the passive selection of building products from catalogs of standardized components that Modernists might have surrendered to. In the twilight years of High-Tech design, HSBC marks a transition from glamorized technology and expressive servicing in the design of buildings to a more complete commodification of technology in the service of architecture.
The following are some of the salient aspects of the design process for HSBC:
• There were 2500 sketch assembly drawings by the architect.
• More than 100,000 shop drawings and 50,000 architectural drawings were eventually produced.
• There were 12 principal contracts and 80 subcontracts.
• Mock-ups and prototypes were refined and tested for the architect’s approval in factories all over the world.
• The mechanical contractor sent 50 people to work at Foster’s office in London for three months.
• None of the mechanical pods are completely identical, because of complications and variations introduced as the design progressed.
• Fabrication of custom cladding began long before other design decisions were made.
• The construction manager was removed from construction activity.
• The cladding contractor built a robot-controlled assembly operation for the project, and the elevator contractor developed lift technology for the building in conjunction with the NASA space program.
The First Consortium on Advanced Technology in Architecture was held at the Harvard Graduate School of Design in 2000. The discussions and presentations focused on the merging of three computer fields: architectural design as computer-aided design (CAD), engineering modeling as computer-aided engineering (CAE), and fabrication control as computer-aided manufacture (CAM). An example of their integration was given as a component design being exchanged between the three respective parties until it was refined to its essence and to the satisfaction of all concerned—without ever risking time and resources for physical testing and development. Other marvels were also present at the conference: a threedimensional copier in the lobby for replicating small objects, and a Web site that would bid on fabrication of any object from a three-dimensional CAD model in 15 minutes. Architects spoke about the design possibilities; contractors addressed the cost control and coordination involved; manufacturers touted their six-axis milling machines and 100,000 psi water-jet saws. Boat makers assured one and all that CADCAM was old hat to their success in making watercraft both more economically and of higher performance. Boeing maintained that the 777 could not have been built without it. Car makers spoke of a new car requiring new robotic assembly design, requiring in turn a new factory. All in all, advanced technology seemed like the next step in High-Tech Modernism. It was easy enough to imagine a project like the Hong Kong and Shanghai Bank that would take the next step.