A Pilot Architecture Project for Sustainable Development in Taiwan - An Engineered Wood Building for The BEST Center Chi-Jen CHEN Ph.D., Assistant Professor, Graduate Institute of Urban Development and Architecture, National University of Kaohsiung, Kaohsiung City, TAIWAN Summary Global warming has increased the frequency of extreme weather events and, thus, various adverse social and economical changes are likely to occur as a result. Therefore, the Kyoto Protocol declared an international consensus on the issue of greenhouse gas emissions reduction and so it also becomes an important common issue for the international community. Being a highly populated, industrialized country, Taiwan is gradually facing the problems arising from different environmental impacts due to the production and construction industries, for instance: high energy consummation, waste emission, air and water pollution, and the sick building syndrome. Consequently, it is urgent to establish a feasible policy in response to the demand for sustainability in the field of construction for Taiwan. Wooden buildings are usually well known by their ecological and sustainable advantages, especially on the use of eco-materials as well as the low-emission construction process. In order to study the appropriate concept and to demonstrate the possibility and the potentiality of wooden buildings for public facilities in the southern Taiwan, an architectural project has been thus launched and been supported by authorities as a pilot project by designing and constructing a wooden building in the campus of the university. The main themes of the project consist of timber structural design, passive design corresponding to local climate and the use of renewable energy. The focal points of the project emphasize not only the engineered needs resisting earthquake and typhoon in the region, but also the integration of different policies concerning the sustainable development in the country, such as green building and the green material labeling system, the green campus and ecology engineering. This paper will present this studied case from its initial concept, through the design process and the engineering considerations to the final results. 1. Introduction and Background 1.1 Kyoto Protocol Since the Industrial Revolution, human consumption of fossil fuels has increased the release of greenhouse gases (GHGs) into the atmosphere and contributed to rising global surface temperatures and climate change. It has been over two years since the Kyoto Protocol entered into force on February 2005, and decisions on the economic development and environmental protection of many economies are continuously being affected by the Protocol. As an island country vulnerable to the effects of climate change, Taiwan also ranks 22nd in terms of GHG emissions (about 1% of the global total). Therefore, coping with climate change is an esential part of Taiwan s sustainable development efforts. Having the natural environment of a subtropical island, Taiwan is very vulnerable to the impacts of climate change. Efforts are now underway to comprehensively assess the potential effects of climate change on Taiwan. In particular, the impacts could include a rise in the energy cost and a lack of natural resources, as well as adverse effects on primary industries, public health, and total ecosystems. 1.2 Green Building in Taiwan Similar to many emerging countries, although Taiwan has its own traditional construction culture and building types such as Chinese traditional houses, the modern Taiwanese construction industry adopts large concrete buildings where in urban or rural regions. The over use of concrete induces not only more pollution factors but also more energy consumption as well as the reduction of limited natural resources like sandstone for aggregate.
Since the international community raised awareness of the importance of global environmental protection at the Earth Summit 1992, pursuing sustainable development has become the wave of the future worldwide. The people of Taiwan realized that sustainability should be one of the most urgent issues for our living environment. In response to public concerns, the concept of Green Building and its corresponding policies were initiated by the public sector. In order to strengthen the development of Green Building, powerful policies play an absolutely important role. The "Green Building labeling" essentially forges a comprehensive mechanism providing resources, research, guidance, training, and education to support the adoption of green building in Taiwan. The major work emphasizes on site ecological environment technology, construction waste reduction, building energy conservation, natural resource usage, indoor environmental quality control, and green building demonstrative projects. 1.3 Problems and challenges in Taiwan Most of the existent wooden buildings in Taiwan were built over five decades, although wood construction seems quite practical in a seismic prone zone like Taiwan, however many advantages and the particularity of this type of construction are vanishing in the modern market. The project looks forward to addressing the following issues: To mature the new construction regulations as well as new technical know-how. To enrich the experience of engineered wood application in practice/ To increase the confidence of consumers as well as professionals and academics To accumulate engineering experience To establish diversity by adapting new material and technique into the market. 2. Goals of The Project 2.1 Sustainability of Construction Not only the mentioned "Green Building labeling" is involved to increase the sustainability of the building industry, another policies are launched by diferent governmental departments such as Sustainable Campus, Green Material and Ecological Engineering, which conduct the same concept in Taiwan. In 2006, the National University of Kaohsiung (NUK) established a center for Built-Environment Sustainable Technology (the BEST Center) and proposed a pilot project considering different phases of the building industry to demonstrate a sustainable program by realizing a experimental wood construction on campus. The goal of this project is in one way to demonstrate the possibility of using wood material as a primary component in buildings without technical obstacles, and in another way, to declare the sustainable meaning of wood construction that is probably a promising solution for reducing environmental impact in the field of the building industry for Taiwan. 2.2 Platform for Promoting Wood Construction Fig. 1 shows the connections of different policies and trends, from where the BEST Center initiates the Demo Building Program. The Demo Building is designed as a technical and conceptual platform, which will experiment with the different issues during the design process and after the erection. The various issues consist of the choice of material, the vernacular constraints (climate and environmental conditions) and the structural design and details. The Demo Building is more than a single and simple building, with its open design, not only the building itself can evoke the practical discussion, but also the different activities such as an in-situ construction workshop and a training program will be held. The short-term goals of the BEST Center and building are: (1) to promote wood construction in Taiwan, (2) to be a platform for exchanging international experiences on wood construction, (3) to be an education center of wood construction, (4) to research the eco-architecture design, and (5) to link industry and academic resources for green materials and eco techniques.
Fig. 1 Organization of Project 3. Design Concept 3.1 Environmental Quality The island of Taiwan is located in the Western Pacific between Japan and the Philippines off the southeast coast of China, from which it is separated by the Taiwan Strait. Crossed by the Tropic of Cancer, Taiwan has a subtropical climate with the exception of it's extreme southern tip, which is tropical. With an average annual precipitation of 2,471 millimeters, rainfall is abundant. However, the distribution of water resources is uneven, making the water available for use per capita low. Thundershowers and the occasional typhoon bring heavy downpours in the summertime, whereas November through February is Taiwan's driest period. Summers are long and humid, while winters are short and usually mild. The average monthly temperature in the lowlands is 16 in the winter and ranges between 24-30 C the rest of the year. Kaohsiung city is hot in the summer months but from October to March the weather is mild with few cold days and little rain. In order to obtain an optimal environmental quality, it is essential to analyze the construction site considering different factors for space organization as well as for climate status, as shown in Fig. 2.. N Fig.2 Site Analysis
It is important to emphasize the passive design in this project. Shown in Fig. 3, the building profile is designed to conduct the natural ventilation that adjusts the interior microclimatic quality without high energy consumption. The ground floor functions as an open space and working area. The raised second floor is cut into several compartments for specific uses like atelier and offices, see Fig. 4. The space below the raised floor can be use as a longitudinal gallery, which can dispel the hot air and the humidity in summer. Besides, the appropriate low-emissivity cladding is applied on the southern façade to reduce the solar gain and to the energy saving. Fig.3 Natural Ventilation as Passive Design Fig. 4 Plans of Demo Building (left is the ground floor and to the right is the second floor) Fig. 5 shows explicitly the interior sides with the space relationship between the ground floor and the second floor. The compartments on the second floor have a longitudinal balcony towards the inside. Fig. 6 shows the integration between the building and the site environment. The light weight structure manifests the minimal land occupation and the less required concrete foundation. It is important to note that the wood building is ideal for the educational field and community public space. The ecological awareness is stimulated by such a sustainable building type. Fig. 5 Interior View of Demo Building
Fig. 6 Exterior View of Demo Building 3.2 Structural Innovation The post and beam system was chosen as the structure system of the Demo Building to obtain the maximal flexibility of space and design. However, more experimental concepts of structure design could be included to reveal the innovation of the program. Fig. 7 shows hoe in the study the X type post is decided upon after comparing the buckling effect of different systems. Fig. 7 Study of Buckling Effect of Post System As one of the most effectual wood materials, laminated wood will be use for the main structure frame. To optimize the material and structural efficiency, the variant sections of laminated wood beam are designed according to study by structural analysis. Fig. 8 shows the study result on the maximal moment of continuous beam and hinged beams.
Fig. 8 Study of Roof Loading on laminated wood Beams 3.3 Exploitation local Resources The picturesque terrain of Taiwan has the reputation of being Ila Formosa, meaning "beautiful island" due to its nurtured forests. According to the results of The Third Survey of Forest Resources and Land Use in Taiwan in 1995, forestland occupied 2,102,400 ha; this is relatively 58.53% of the total island area, which is 3,591,500 ha. Among the forestland 76.7% or 1,642,900 ha is national forest. Occupying 1,120,400 ha, hardwood forests exist as the major forest type on the island, followed by 438,500 ha of conifer forests, 391,200 ha of mixed conifer and hardwood forests, and 152,300 ha of bamboo forests. In order to keep the biodiversity, and ecological balance as well as environmental quality, local forestry resources must be retained and managed in a sustainable way. Taiwan used to be one of the most important Asian countries for exported lumber and wood based materials, but nowadays, most of the commercial wood is imported since the exploitation of forest in Taiwan was restrained in 1970. This project attempts not only to introduce the modern concept on wood construction, but also to encourage the use and the application of local wood material which may revitalize the forestry industry in Taiwan. Instead of using imported laminated wood as the main structural components, various local wood (spruce, pine, cypress, and even bamboo) will be exercised for the rest of the wood components depending on the different requested functions. 3.4 Feasibility and Local Skill Another important task of this project is to promote wood construction adopting the local construction industry. Although many commercialized and patented systems can be introduced into Taiwan s domestic market, how to transfer the technical know-how and the feasibility of erection is nevertheless the most important consideration in short-term development of wood construction for the country. The details of the Demo Building shown in Fig. 9 are developed taking into account the capacity and usual practice of local labor in Taiwan. Fig. 9 Details of Joints (from left to right: column, bracing and rafter)
4. Conclusion This paper addresses one pilot architecture project with which the authorities would like to promote wood construction as an alternative for modern construction market in Taiwan. The concept design and all key considerations of the Demo Building are illustrated in this paper. With good coordination and connection to industries and experts, the debut of a new wood building on campus has a multiphase benefit. The building itself could provide an effective educational platform. The design process could combine with the teaching program as well as be a technical forum or workshop, which should boost the local development of wood construction. 5. Acknowledgement This project is subsidized by the Ministry of Education of Taiwan. The author appreciates this support and encouragement. 6. References [1] Forestry Bureau of the Board of Agriculture, the Executive Yuan, Taiwan. http://www.forest.gov.tw/ [2] Environmental Protection Administration, the Executive Yuan, Taiwan, http://www.epa.gov.tw/ [3] Chi-Jen Chen, Technical report of the BEST centre, The Project of Promoting Large Public Wood Building-Demo Building, 2007, Taiwan