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1.0 INTRODUCTION TO THE NATIONAL LIBRARY OF SINGAPORE

Rising 16 storeys and standing a 102.8 metre away from the ground is the gigantic

edifice of Singapore National Library building. It sits on a square site bounded by Victoria

Street in the north, North Bridge Road in the south, Middle Road in the east and the small filter

lane of Bain Street in the west and takes up an area of 58,7833 sq metres.

The infrastructural planning for the building started with a public consultation process.

As early as May 1999, seven civic groups were set up to collect public views and response on

the construction of the New National Library Building. These were made up of business

community, community self-help groups, arts community, older citizens, disabled persons,

young people and researchers.

Figure 1.0(a) Site Location

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Figure1.0(a) shows that National Library building represents the converging spaces of

arts, heritage and libraries stacked vertically up with two connected wings of programming

zones where collaboration and high interaction takes place. The architecture integrates public

and entertainment space, with that of reference and research converged in a single building.

By raising the collections block one story off the ground, the architect created a central

atrium space covered by stacks of thermal masses on top. This structure encourages airflow

from outside to the interior space through the inlets, creating a cool internal civic space (Kwok,

2011). Likewise, the covered atrium runs north-south to capture breezes and to frame the view

north to the historic St. Joseph's Church across Victoria Street. The design of the library

addresses the contradiction that its requirements present the books need to be kept away

from direct sunlight, extreme temperature and moisture, while adequate daylight is to be

ensured for reading.

Figure 1.0(b)Spaces in National Library Building

Figure 1.0(c)Stack Ventilation Effect

wind

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Figure 1.0(d)Plan showing building layout

The huge civic project that opened to public in 2005 is separated into two different blocks,

which carefully oriented away from the east-west sun to minimize solar impact. It consists of a

banana-shaped structure on the east for exhibition spaces and cultural activities and sun

shading features on the west face of the building that would house the library collections and

reading rooms as an additional shield against solar heat gain. The forms of the blocks reflect

their inner functions a large, rectilinear block meant for the library collections and a smaller,

curved block for the noisier, public activities. This contrast between the formality of one and

asymmetry of the other reveals the dual nature of the library. A semi-enclosed, daylit street runin between the two pieces, with bridges at the upper levels connecting the two sides.

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1.1 Macro Climate Analysis

Figure 1.1(a)Diurnal Weather Averages

Figure 1.1(b)Dry Bulb Temperature from 1 Jan to 31 Dec

Figure 1.1(c)Relative Humidity from 1 Jan to 31 Dec

Figure 1.1(d)Direct Radiation from 1 Jan to 31 Dec

1.1.1 Climate Data

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At the floor level, the temperature is about 25oc with velocity of up to 1m/s or higher. At

the section in the middle of the space, the temperature is around 26-27oc and the velocities

vary from 0.1 to 0.6 m/s. The air velocity distribution varies quite significantly across the

space, generally from 1m/s to as high as 4.5 m/s in certain spots. Given the assumed

prevailing wind direction, the fully enclosed link bridges act as a barrier which deflects the

wind downwards and accelerates the flow along the Street towards Victoria Street. There is

also negligible air movement in the vertical core between the link bridges under naturally

ventilated conditions (Janeiro, 2001).

A canopy at the base of the lowest link bridge is applied to avoid area of high air

velocities in the plaza. Similar element is also introduced at the perimeter of the main library

block along Victoria Street and North Bridge Road. These elements serve as effective screens

against potential driving rain into the plaza area.

Figure 1.2.1(c) Canopy


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The new National Library Building is the first building to achieve the highest award for

the Green Mark Scheme the Green Mark Platinum, it also receive an award from the World

Association of Chinese Architects. The building was designed as an innovation architecture,

which incorporated bioclimatic design techniques, advanced mechanical and electrical

engineering. The building had to be able to respond to the tropical climate. It is very

uncomfortable for its occupants and threatened the important collection due to the solar heat,

humidity and light. Hence, it is operating in an energy efficient way by having several innovative

green features. Computer simulation and modelling was carried out to find the best building

orientation and configuration to buffer from direct solar heat, at the same time optimising

natural ventilation and day lighting (Hart, 2011).

Figure 1.2.2(a)Stereographic Diagram

Figure 1.2.2(b)Composite of Buffer Zone

1.2.2 Solar Analysis

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Effective Shading facing Victoria Street

Figure 1.2.2(c)Percentage of the faade area shaded for each month

Total Incident Radiation facing Victoria Street

Avera

geHourlyRadiation(x10-3 k

Wh)

Perm

2

Figure 1.2.2(d)Hourly solar radiation incident on the facade for each month

Figure 1.2.2(c) shows the measure of the shading efficiency of different height of

faade/depth of shade ratios (h/d) in terms of percentage of shaded areas while Figure 1.2.2(d)

shows the solar radiation (kWh/m2) incident of the faade. The self-shade condition represents

shading that occurs simply by virtue of the faade orientation, for example, the east faade will

not receive any direct solar radiation in the afternoon period. This indicates that the Victoria

Street and Middle road facades are generally more exposed to incident solar radiation all year

round than the North Bridge Road and Bain Street facades. Hence horizontal shading is

applied to reduce the incident radiation on all facades (Janeiro, 2001).

PercentageofFaadeArea

(%)

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1.2.3 Energy Efficiency

There are only some part of the building is fully air-conditioned; while the covered plaza

is naturally ventilated and mostly day lit, and transitional spaces such as lobbies and foyers

use a combination of natural ventilation and mechanical means, such as fans. Louvers were

installed in the glass roof above the atrium, which creates convection force to pull hot air up

and out of the space. Most of the other spaces are naturally ventilated and cooled by the 14

garden terraces, equals to nearly 70,000 square feet of planted areas. Extensive landscaping

and sky terraces are utilized to lower local ambient temperature while the two sunken

subterranean gardens reduce humidity of the basement.

Besides motion sensors to switch off the lights in some of the public spaces during the

day, daylight sensors at the boundary of the library areas also monitor the amount of natural

light entering the building, allowing the artificial lighting to switch off and reduced the building

dependence on the usage of electric lighting. The libraries, exhibition and office spaces are

largely naturally lit. A sophisticated Integrated Lighting Control System allows for strategic

programming of the internal and external lights. Localized intelligent switching provides

afterhours lighting only for occupied areas (Yeang, 2005).

Table 1.2.3(b)Measurable Results

ENERGY SAVINGS 31%

DESIGN ENERGY SAVINGS 17% lower than the National Library Buildings

design benchmark

ELECTRICITY ENERGY SAVINGS 31% lower than the national average of 220kWh/sqm/annum for non-green buildings

ENERGY EFFICIENCT INDEX (EEI) 151kW/hr/m2

Figure1.2.3(a)Daylight sensors monitor the amount of natural light entering the building, allowing the artificial

lighting to switch off.

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