28 August 2007
In Taipei City's Beitou Park (台北市北投公園), there is a brand new public facility that is being hailed as Taiwan's greenest building.
The Beitou Branch of Taipei Public Library (台北市立圖書館北投分館), which formally opened in November 2006, is the first building in Taiwan to qualify for a diamond rating—the highest possible—under the government's EEWH certification system (EEWH, 綠建築指標) for sustainable construction projects.
Green buildings like the library aim to minimize harm to the environment through the use of recycled or renewable materials, and by being energy and water efficient.
Taiwan's government was the first in Asia, and the fourth in the world, to adopt a set of sustainable building standards. The EEWH system—so called because it focuses on Ecology, Energy saving, Waste reduction and Health—is roughly equivalent to LEED (Leadership in Energy and Environmental Design Green Building Rating System) in the United States, and CASBEE (Comprehensive Assessment System for Building Environmental Efficiency) in Japan.
The library's wooden walls hark back to Japan's occupation of Taiwan (1895-1945), during which period thousands of buildings were constructed of timber felled from the island's forests. Its shape, however, and the vast amount of window area for its size, make it very different in appearance to Beitou's few surviving Japanese-era bungalows.
The use of wood is significant. If taken from managed forests rather than primary or rain forests, it is a far greener material than concrete. Cement takes a great deal of energy to extract, heat, mix and refine. Also, the extraction of gravel for use as a concrete aggregate has damaged many of Taiwan's rivers and hillsides.
Ying-chao Kuo (郭英釗), one of the architects who worked on the project, explains that the timber for Beitou Library was sourced from North America. It could not be obtained from anywhere nearer because logging has been effectively banned in Taiwan, and forests in Southeast Asia are not managed in a sustainable manner.
Taiwan's hot, humid climate and insect population can be brutal for wooden structures. But rather than treat the materials with strong chemicals that might later contaminate the environment, wood oils were used to protect the timber from rotting and infestation, says Kuo, one of the partners of the Taipei-based firm Bio Architecture Formosana (九典建築師事務所), the designers of the library.
The library's large windows help cut electricity use in two ways. An abundance of natural light means less interior lighting is needed. Also, the windows can be opened to provide ventilation, so reducing the need for fans and air-conditioning.
One part of the roof is covered by photovoltaic (PV) cells that are expected to convert sunlight into at least US$1,000 worth of electricity per year. Another part is covered by a 20-centimeter-thick layer of soil that provides thermal insulation. During Taipei's chilly winters, the soil cuts heat loss through the ceiling and thereby makes the interior cozier. In the summertime, the foliage blocks some of the warmth of the sun.
Some plants take root and thrive on the roof, improving air quality in the immediate area. However, says Kuo, it is not a rooftop garden, and so requires neither watering nor maintenance.
The library conserves water by capturing rainfall. The sloping roof gathers rainwater, which is then stored and used to flush the library's toilets.
Easy access to public transportation, which inevitably reduces car use and carbon dioxide emissions, is not part of the EEWH assessment system, though it may be added in the future. In any case, Beitou Library does superbly in this respect. It is six minutes' walk from Xinbeitou MRT Station, and at least 14 city bus routes stop within three minutes of the entrance.
However, things are not made especially easy for cyclists. There are no racks for chaining or locking bikes. According to Kuo, this is because the library lies within a park, and Taipei City Government by-laws stipulate that bikes are not allowed inside parks. During the design phase, Bio Architecture Formosana did manage to obtain an exemption from another law, that requiring all public buildings to have car parking spaces.
The Beitou building is not Taipei’s only green library. The Shihpai Branch of Taipei Public Library (台北市立圖書館石牌分館), another Bio Architecture Formosana design, was opened to the public in late 2006.
From within and without, Shihpai Library looks much more like a conventional building than its counterpart in Beitou. Kuo explains that this is because it was designed much earlier than the Beitou building, and also because it needed to have a lot more floor space—6,740 square meters (including a nursery), compared to 1,990 square meters—while occupying a much smaller plot of land.
Nonetheless, the architects were able to incorporate several green features, including a roof shaped like a billowing sheet that captures rainwater; a corner cooled by winds from three directions; water-efficient bathrooms; a forecourt paved with water-permissible bricks; and a rooftop garden.
Various government bodies are helping to promote sustainable building in Taiwan. Taipei City Government (台北市政府), which commissioned the Beitou and Shihpai libraries, was, Kuo says, "a very nice client." The Ministry of Economic Affairs' Water Resources Agency (經濟部水利署) encourages the capturing of rainwater. The state-run Taiwan Power Company (Taipower, 台電公司) is obliged to buy surplus electricity generated by PV systems. The Ministry of the Interior's Architecture and Building Research Institute (內政部建築研究所) is responsible for a six-year-long, NT$1.8-billion Green Building Promotion Program (GBPP).
"The program includes mandatory green building design for new governmental buildings, green remodeling and green HVAC [Heating, Ventilation, Air-Conditioning] projects for existing governmental buildings, research and development for recycling building materials, promotion of green building materials, training and education for architects and professionals, as well as other promotion activities for the public," says Chiung-yu Chiu (邱瓊玉), a research fellow at ABRI.
The GBPP stipulates that government-backed projects worth NT$50m or more, and projects receiving government subsidies that account for 50 percent or more of their total budget, need to pass four of the nine indicators that comprise the EEWH rating system.
The nine indicators are: foliage; water soil content (infiltration and retention); energy savings (for lighting and HVAC); carbon dioxide emissions reduction; construction waste reduction; water conservation; garbage and sewage improvements; biodiversity; and indoor environmental quality.
The not-for-profit Taiwan Green Building Council (TGBC) (台灣綠建築發展協會), established in January 2005, is also promoting EEWH. The TGBC brings together building contractors, property developers, household appliance manufacturers, government bodies and academic institutions. It represents Taiwan on the World Green Building Council (WGBC).
According to Chiu, by the end of July 2007 the total number of completed and EEWH certified green buildings in Taiwan was 195. This number may seem small, but by international standards Taiwan is making excellent progress. According to the WGBC's website, only 25 projects in Australia have been certified under that country's Green Star evaluation system. In Japan, just 16 buildings had satisfied CASBEE requirements by the end of 2006.
Alex Hsu (徐鼎皓), one of Kuo's co-workers, says green buildings are typically 10 to 30 percent more costly than standard designs. Despite this, Taiwan's sustainable construction industry is growing. A total of 1,216 projects were being considered for EEWH certification at the end of July 2007, says Chiu. And as of August 2007, Bio Architecture Formosana was working on three more "green" projects—a hillside temple and nunnery on the outskirts of Taipei, a bank building in Yilan County (宜蘭縣) on the east coast, and a dormitory for the employees of a research institute in Tainan County (台南縣) in the south of Taiwan.
Written by Steven Crook for culture.tw
Photos courtesy of Bio Architecture Formosana