Ken Yeang's National Library of Singapore
Beneath this plaza is a pair of partial "ecocells" — vegetated water-collection devices that Yeang first began exploring in his West Kowloon (Hong Kong) Waterfront competition entry.
The smaller, curvilinear block of the library contains facilities for noisier activities such as exhibitions, lectures and multimedia performances. The plaza and "street" at the ground plane have been designed to function as part of the public realm, replete with cafes and retail units.
[an error occurred while processing this directive]
One of the features of this project is that the building benefits from what Yeang calls "passive mode," "mixed mode" and "full mode" features — that is, a variety of energy and environmental solutions that range from the manipulation of building form to the installation of conventional air conditioning.
National Library of Singapore
Architect: T.R. Hamzah & Yeang
Climate Zone: Tropical
Vegetation Zone: Rainforest
Gross Floor Area: 58,783 square meters (632,730 square feet)
Net Floor Area: 44,087 square meters (474,550 square feet)
Site Area: 11,304 square meters (121,680 square feet)
Number of Stories: 15
Date of Completion: 2005
"There is nothing wrong with using electricity," says Yeang. "The bigger issue is how that electricity is generated."
Passive-mode features include optimized daylighting, solar orientation and configuration; sun shading; natural ventilation; responsive facade design; and landscaping. The building's distinctive louvers, which perform solar shading and anti-glare roles, are up to six meters (20 feet) deep in places, and help define a tropical aesthetic for the library as well as serving as light shelves to deflect natural light into the inner parts of the library.
Most of the library work areas (which contain triple-height reading rooms) operate in "full mode," deploying air conditioning and electric light. Mixed mode, in which passive controls are supplemented as necessary, typically operates in transition spaces such as lobbies and foyers.
Computational fluid dynamics simulations, carried out by the National University of Singapore's Total Building Performance Team, were used to predict acoustic performance, airflow and heat loading, demonstrating where passive design techniques would need a mechanical/ electrical boost.
Daylight penetration and energy consumption were also evaluated through computer simulations, while wind-tunnel tests provided the basis for facade design and specifications, as well as for the assessment of comfort conditions in the plazas and semi-enclosed skycourt spaces.
Materials were specified according to their environmental impact over the lifecycle of the building and its associated systems. Studies were carried out on the embodied energy content of the building by engineers Battle McCarthy.
More than 6,300 square meters (68,000 square feet) of this building are devoted to green space in the form of urban skycourts, constituting more than 60 percent of the building's footprint. The northeast facade contains a pair of 40-meter- (130-foot-) high skycourts planted with three-meter- (ten-foot-) high trees.
These skycourts are protected by windbreakers that reduce the impact of the high wind speeds that can occur at higher levels of this 15-story tall building — gusts can reach more than 35 meters per second (78 miles per hour). The windbreakers baffle the wind and break it into smaller, weaker eddies before it enters the skycourts.
Studies show that the environmental impact of the National Library is lower than that of a typical office building of similar size. The energy efficiency index of the building is around 172 kilowatt-hours per square meter per year (16 kWh per square foot per year), compared with the index of a typical office building in Singapore which consumes around 250 kWh/m2/year (23 kWh/ft2/year).
Post-occupancy evaluation has shown that over 90 percent of library users and staff are satisfied with the building, which has also received several prizes, including an award from the World Association of Chinese Architects.
Ken Yeang in Transition
Like any architect with a large body of work extending across a number of decades, Yeang's portfolio of built and unbuilt schemes plots a clear trajectory in which a distinctive language is developed and refined.
Yeang can now, also, begin to identify particular projects as "transitional" ones — those that mark turning points or imaginative leaps which began to take him elsewhere.
This transitional period, covering roughly the late 1990s to the middle of the following decade, was one in which Yeang completed the National Library of Singapore, drew up a series of ambitious master plans, and published widely. Looking back, Yeang describes this as a "period of indeterminacy."
Yeang was also, he admits, exhausted. Apart from developing his theories on architecture and evolving them into a more fully ecological approach, Yeang had been overseeing complex construction works and dealing with the fallout from financial meltdown in Asian markets.
The financial crisis of 1998, in which governments were pitted against international hedge-fund managers, caused many Southeast Asian currencies to drop in value by significant margins. The Malaysian ringgit lost 40 percent of its value, making Yeang (on paper at least) 40 percent poorer almost overnight.
Although busy, much of Yeang's work was not commercial — his conceptual work far outweighed the number of built projects, and Yeang also filled his time entering design competitions, researching and speaking at conferences and international schools of architecture. He took time away from the office to attend a business course on "leading a professional service firm" at Harvard Business School.
During this frantic, transitional period, Yeang managed to hone his ideas about the aesthetics of ecodesign, taking the subject far beyond the generally acknowledged definition of "sustainable design."
He also began to become more certain about the economics of ecodesign, and the ethics of developing in an environmentally sensitive manner.
Moving, perhaps, a little away from notions of "critical regionalism," Yeang grew more comfortable with the idea that green architecture is something which has to be paid for, which can accrue value and which, ultimately, depends on the commitment and moral backbone of the developer.
"Cost control is absolutely crucial. We must design and deliver within the client's budget," says Yeang. "But there will always be a cost premium for ecodesign. We can, of course, present a business case for green buildings, but it is difficult to persuade critics and clients to go green and become sustainable if they are averse to it from the outset.
"We usually present ecodesign as an ethical issue that responsible citizens must address. Fortunately, we are now getting clients who are actively commissioning green architecture from us, rather than having to be convinced that this is what they should have."
At the same time, Yeang started to get to grips with certification systems — largely through his experience of designing the Singapore National Library under the terms of the country's Green Mark system.
Yeang has an ambivalent attitude towards such systems; while they are useful in raising public awareness of the environmental credentials of one building over another, and in providing a framework within which architects can work, he says that systems like Green Mark, BREEAM and LEED cannot pretend to provide comprehensive cover:
"We must be careful about reducing green design to simplistic indexes. Nature is very complex. Yes, there are indexes covering matters such as biodiversity, but even these are subject to debate."
Discuss this article in the Architecture Forum...
Sara Hart received a master of architecture degree from Columbia University. After many years in practice in New York City, she turned to design journalism, specializing in building technology and innovation. She has written extensively about new materials, technologies, and sustainable practices, including as a writer and contributing editor for Architectural Record.
David Littlefield is a senior lecturer at the University of the West of England. He has authored, coauthored, and edited a number of books, including The Architect's Guide to Running a Practice, Architectural Voices: Listening to Old Buildings, and Liverpool One: Remaking a City Centre.
This article is excerpted from EcoArchitecture: The Work of Ken Yeang by Sara Hart, edited by David Littlefield, copyright © 2011, with permission of the publisher, John Wiley & Sons.