The architect, along with the project's structural, civil, geotechnical, acoustic, fire and building services engineer engineers, began the design process with the aim of fulfilling seven key criteria: functionality; flexibility; safety; energy efficiency; sustainability; lifetime economy; buildability; and ease of maintenance.

The first two floors are allocated for undergraduate teaching, while levels three to eight house the research facilities. The use of the floors are flexible and may be changed as when required. The 9th floor is a shared-use space for plant, roof store, greenhouse and aquarium.

2.1 Support Sturcture

The facilities are housed in two very stiff multi-storey concrete boxes that are lifted ten metres above the site and supported on upturned pyramidal columns that limit the foundation supports to just four piles for each box. The boxes are connected at each level by a central core and form highly flexible and highly serviced lab spaces, all with controlled environments.
 

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2.2 The Façade

The Kadoorie Biological Sciences Building is the first building in Hong Kong to fully exploit the green possibilities of a second skin: an external glazed screen which is 2.5 m away from the external wall.

The building is clad in a combination of silver grey ceramic tiles and glass and steel double skin. The north and south facades are clad in ceramic tiles and the windows are protected by sunshading devices. External maintenance walkways surround the building at each floor level, providing safe and easy access for maintenance personnel. According to Leigh & Orange's Associate, Ms. Gabrielle Tsui, the horizontal projections of the sunshade are calculated to strike a balance between solar control and daylight penetration to the interior. 

The east and west facades are clad in a double-skin curtain wall which serves several functions. It acts as a screen for the building services installations distributed around the exterior of the building in order to provide a flexible interior for the laboratories. Having the building services installed on the exterior means maintenance can be carried out without disturbing laboratory users and laboratories are less likely to be contaminated. The security of the laboratories is further enhanced by the provision of access to the building services through external ducts and staircases.

The outer skin is made of fritted glass, which is a cost-effective means of reducing solar radiation. In order to allow natural light into the laboratories, the engineer calculated the angle at which sunlight would enter the building and had the fritted glass fitted accordingly, alternating with bands of clear glass, which allow natural light to pass through.
 

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2.3 The Interior

With building services installations moved to the perimeter of the building, the interior space is completely freed up for laboratory facilities, which are served by a central core which, in addition to connecting the two multi-storey laboratory structures, also functions as a circulation core.

According to the architect, maximum flexibility and adaptability governed the design of the laboratory suites. Thought was also given to energy efficiency and waste reduction. Each suite is a 3 m high, 24 m by 24.6 m shell with smooth, flush and easy to clean surfaces. The suites are subdivided into 600 basic units using easily removable metal partitions, which are pressure-fixed between the floor and the suspended ceiling.

The partition supplier, Clestra Ltd, developed a partition, which offered the required rigidity and acoustic performance at a thickness of 60 mm only. The partitions not only offer flexibility and rigidity, but also great functionality. Aluminium wall rail channels fixed on the partitions allow light switches, power sockets, shelves, cupboards, whiteboards and coat hangers to be simply hung while remaining movable. Smaller fixtures such as picture hooks and task lighting can be placed anywhere on a partition by using magnets. This provides further flexibility and adaptability to the need for change of usage in the internal space.

The floor is paved with linoleum which, unlike artificial vinyl, is a natural, biodegradeable material. The design concept of flexibility is consistent throughout, including the internal fitting works. The modular design extends to the laboratory benches, which are in the form of pre-plumbed/serviced spine units, which can be bolted together in various combinations according to the layout.
 

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Between the Double Skin 

The space between the double skin is not only used to accommodate the building services, but also used as an external buffer zone between the two layers of glazing, which acts as a stack that channels hot air upwards for discharge into the air, thus reducing the building's solar heat gain. An open metal grille installed at each floor allows free air circulation while serving as walkways for maintenance access. Heat gain is further reduced by locating heat emitting equipment in the external services zone outside the building, where they release their heat into the void rather than the interior. The design means that the building's air-conditioning system is used only to cool the space and not to overcome solar heat gain, thus dramatically improving the system's energy efficiency.

By locating heat-emitting equipment in the external services zone and using an external glazed wall as a sunshading device, without taking into account various other energy-efficient and environmentally-friendly design features in the building, the architect estimated that savings of 53,360 kWh of energy per year, or 2.67 million kWh over 50 years, can be achieved. Carbon dioxide emission is expected to be cut by 37.6 tonnes per year or 1.88 million tonnes over 50 years.

Ceiling

The suites inside the building are subdivided into 600 basic units, but eh configuration is entirely flexible. All services are routed through the ceiling, which consists of a 3m by 3m ceiling grid containing all necessary services for laboratory functions, including compressed air, gases, electricity and telephone outlets.

Services are routed into the 1.5 m deep ceiling void on each floor from the services spine. Flexible connectors distributed according to the 3 m grid allow all the services needed to be hooked up easily for instant "plug-and-play".

Drainage provisions in the floor are also provided according to the 3 m grid. With ease of maintenance in mind the engineer designed a vacuum drainage system which sucks all drained material to a temporary store in the ceiling before final removal via ducting connected to the service core.

Fume Cupboards

The building is equipped with two types of fume cupboards: one which extracts hazardous fumes directly through the roof ; and a recirculatory fume cupboard for non-hazardous vapour.

The latter kind is a particularly green feature of the building, which only became commercially available recently. Developed by the British Atomic Research Authority, the fume cupboards utilise vortex fume scrubbing technology which, together with built-in carbon filtration, make them recirculatory, thus cutting down on the air-conditioning load of the building. Since they are moveable, these fume cupboards also contribute to the layout flexibility of the laboratories. As they do not require a fixed rooftop scrubber and extractor, a whole floor of plant space was freed up, which allowed the architect to produce additional space to accommodate the later added Institute of Molecular Biology. The re-designed roof also accommodates greenhouses and an aquarium.
 

3.2 Building Services Drawings
(* Plug-in viewer, e.g. WHIP,  is needed on the browser to view the DWF files)

MVAC
D-AC103C.dwf  - MVAC water side schematic diagram
D-AC105.dwf   - Fume extraction system schematic diagram
SK224_5.dwf   - Typical air handling unit controls
D-CS302.dwf   - Proposed lab MVAC/exhaust system
DGM-1.dwf     - Proposed chiller arrangement
DGM-2_3.dwf - Chilled water pumping schematics
DGM_4.dwf    - MVAC air side schematic diagram for lab module

Fire Services
D-FS101.dwf   - Automatic sprinkler system schematic diagram
D-FS102.dwf   - FH/HR system schematic diagram
D-FS103.dwf   - Automatic fir alarm system schematic diagram
DR-FS104.dwf  - Drencher system schematic diagram

Plumbing & Drainage
D-PD101.dwf   - Portable water system schematic diagram
D-PD102.dwf   - Flushing water system schematic diagram
D-PD103.dwf   - Drainage system schematic diagram
D-PD104.dwf   - Storm water system schematic diagram

Electrical Services
D-EL101C.dwf  - LV electrical schematic diagram
D-EL103.dwf   - Security system & CCTV system schematic diagram
D-EL104.dwf   - BMS system & PA system schematic diagram
DR-EL201.dwf  - Cable containment layout at typical floor

Other Utility Services
D-AU101.dwf   - Combined existing utility services routing plan
D-AU102.dwf   - Proposed permanent utility connection
D-CG101.dwf   - Compressed air/vacuum plant schematic diagram
D-TG101.dwf   - Town gas system schematic diagram

Combined Services Layouts
D-CS201.dwf   - M&E combined services layout for typical lab unit
D-CS202.dwf   - M&E combined services sections & elevations for typical lab unit
D-CS203.dwf   - M&E combined services layout on G/F
D-CS204.dwf   - M&E combined services layout on P/F
D-CS205.dwf   - M&E combined services layout on 1/F - 7/F
D-CS206.dwf   - M&E combined services layout on 8/F
D-CS207.dwf   - M&E combined services layout on 9/F
D-CS208.dwf   - M&E combined services layout on U9/F

Laboratory Areas
DR-CS303.dwf  - Demarcation of work between BS installation and lab bench fitting-out
DR-CS304.dwf  - Typical longitudinal section through lab area
DR-CS305.dwf  - Section through external open services zone

Facade Detail
DGM-5.dwf    - Facade construction detail
 

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4.1 Construction Programme
 

Demolition (April 96 to Mar 97) BD Submission for Hoarding  BD Submission for Demolition  Tender  Actual Demolition  Site Investigation (Mar 96 to Sept 96) BD Submission (required for schedule area) Tender  SI works

Site Formation / Foundations (Sept 97 to Jan 98) BD Submission for soil nails and slope reprofiling, piled foundations.  Tender  Construction  Superstructure (Mar 97 to Oct 99)  BD Submission for General Building Plan  BD submission for Superstructure  Tender  Construction  Hand over to HKU

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4.2 Concept/Scheme Design

• Establish structural forms by exploring options
• Schemes were developed in collaboration with HKU, architect and services engineers
• An efficient structure form was derived taking into account following:
• Structural performance
• Client requirements (end user)
• Architectural requirements
• Building services routing
• Ease of construction (buildability)
• Cost of construction

Two-way slab	Structural grid	Ribbed slab	Loading assumptions
Waffle slab	Roof scheme	Roof isometric	Connection of "V" column and plinth concrete

Wind Loading

• Wind loading was assessed using HK Wind loading Code
• The wind loading on the curved roof profile was established using empirical data from textbooks.
• Due to the gaps in the glazed screen with opened ends, advice was sought from ARUP R&D in London to see if there were any increase in loading. 
• Suction at the edges was increase due to the opened ends of the services zone.

• The foundation system adopted for the building was large diameter bored piles.
• 1 no. 2.5 m diameter pile with 3.6 m bell out were positioned underneath each of the "v" column groups.
• For the 4 bored piles closest to the slope, compressive sleeves were used to prevent lateral loads being exerted on the soil and retaining wall.
• Concrete ground beams are used to connect the top of the piles together.

• The slope and existing retaining wall was trimmed down to a lower level to improve the site for the new building.
• Soil nails were inserted through the wall into soil prior to maintain stability prior to trimming.

Undeformed shape

Deformed Shape

• Stability 
• The stability system adopted is the moment frame (no shear wall).
• The central core wall provides additional stiffness to the system. 
• The building deflection was computed from proprietary computer software, ETABS.
• Due to stiffness requirements of the slab and beams of the floor, the building is actually a lot stiffer than code requirement hence lateral movements are low.
• Floor system 
• 450 mm waffle slab spanning onto 450 mm deep beams. 
• The primary beams span continuously on a 9.0 m grid.
• Beams were designed to incorporate the frame moments from the stability model. 
• The flat soffit of the beams and slab meant that services could be easily installed without the need for specially cut openings. 
• Columns 
• The columns are spaces on a 9.0m grid for the typical floor which reduces in size further up the building. 
• The columns converge between the 1st floor and ground to give its distinctive form. 

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Roof Section

• The exposed steelwork elements: 
• Roof
• Entrance Lobby 
• Canopies 
• Glazed Screen 
• The roof steelwork comprises bent circular hollow sections spanning between the roof and 9th floor.
• The lower tie member helps to control spreading of the CHS as well as providing the vertical support for the glazed screen.
• The connection details for the various elements have been designed in collaboration with the architects.
• The Entrance Lobby can be easily seen from the road level.
• A fully glazed, exposed steel structure incorporating visual details was designed.
• The structural form follows the 3-pin arch principal to obtain its stability.
• The knee joint is clearly expressed as a pin connection.
• The Northern Canopy is situated over the main entrance staircase.
• The structure hangs from the concrete staircase via a series of ties and struts.
• The ties and struts work in tension and compression depending on the direction of wind loading.

5.1 From Our Study
(* Some photos were contributed by BA(AS) Year 3 students of 1999-2000 taken during a site visit.)

Design Models and Concepts:

Early design model

Initial design

Initial design

Initial design

West elevation

Double-skin concept

Exterior:

Interior:

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5.2 From Building Journal
 

Branton, T., Drake, F. and Smith, T., 2001. The compliant laboratory: new biological sciences facilities at the University of Hong Kong, International Labmate, Volume XXVI, Issue III, Guide 2001/2002. (http://www.product-search.co.uk/internationallabmate.com/features/guide2001-2002/new-facilities.htm)

Howe, K., 2000. The green light, www.totallyHK.com.

"Kadoorie Biological Sciences Building: Beneath the second skin", Building Journal Hongkong China, June 2000. (http://www.building.com.hk)

Kadoorie Biological Sciences Building, Hinge Magazine, 37 (1997): 34.

Lee, I., 1998. Versatile building services design for the Kadoorie Biological Sciences Building, PB Network, Volume XII, Number 1, Issue No. 41, Spring 1998, pp. 14-15.

Tam, A., 2001. Setting the trend for a greener skyline, Hong Kong Engineer, 29 (2): 13-19, Feburary 2001.

• Biological Science Building - A State of the Art Laboratory for HKU [L&O]
• Construction in Kadoorie Biological Science Building [HKU Estates Office] [Other photos]
• Opening Ceremony of Kadoorie Biological Sciences Building [HKU Faculty of Science]
• Kadoorie Biological Sciences Building (structure and construction) [CIVCAL at HKU]
• Kadoorie Biological Sciences Building Photo Library [Building Journal Hongkong China]

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• Mr Ian Y. L. Lee, Parsons Brinckerhoff (Asia) Ltd.
• Ms Gabrielle Tsui, Leigh & Orange Ltd.
• Mr Wan Chi Wai, Ove Arup & Partners
• Represntatives from Estates Office, The University of Hong Kong