A Bangkok Shophouse Support and Evaluation by Thai Architects

Journal of Habitat Engineering and Design XXXX Volume X, Number X, XX-XX A Bangkok Shophouse Support and Evaluation by Thai Architects Chamnarn TIRAPAS Doctor Candidate, Department of Architecture and Design, Graduate School of Science and Technology, Kyoto Institute of Technology Matsugasaki Sakyo-ku, Kyoto, 606-8585, Japan; [email protected] Katsuhiko SUZUKI Professor, Department of Architecture and Design Graduate School of Science and Technology, Kyoto Institute of Technology, Dr. Eng. The shophouse is one of the flexible housing types in Thailand. To increase its flexibility, a shophouse support is proposed. In this study, the proposed shophouse support is examined for a prospective implementation of the support-infill concept in Bangkok. The study investigates the concept understanding, the method of variation design of support, and the quality assessment which are creativity and variety, functional extendibility, and convertibility. Thus, the proposed shophouse support survey was sent to 35 voluntary Thai architects to design their layouts based on the given shophouse support and to provide feedback for an evaluation. The result reveals that the concept and the method are accepted and have potentials for application. However, a simple explanation and comfortable procedure are required. The test shows that the shophouse support quality is also accepted. Nevertheless, building renovation regulations should be included as a criterion for a new support design and as a flexible factor. In addition, improvement of prefabrication and infill system are advised to promote the support-infill in practice. Increase of flexibility acknowledgement and undetermined functional design are also recommended for promoting the method and the future shophouse support and design. Keywords: Bangkok Shophouse, Flexibility, Open Building, Support-Infill, Evaluation 1. Introduction The Bangkok city development direction is now a sprawl development. This has been illustrated in various studies (Klinmalai & Kanki, 2013; Meesiri & Perera, 2011) and urban development policies (Pornchai, 2010). To solve the urban sprawl city, the compact city concept is considered as one of the dissolutions. However, its concept is applied to deal not only with compactness and transportation matter, but also with size, diversity of use, block structure, housing type, and etc. (William, et al. 2001). In addition, the land use separation concept has been applied to the Bangkok city development. However, in practice, the separation of activities is not befallen. The city activities are mixed and combined with various purposes of use. This is, as a result, utterly served by shophouses across the city. The shophouses are the well-known mixed-use buildings in Thailand. The bi-functional use is its major characteristic; commercial purpose on the lowers floor and residential purposes on the upper floors. Normally, the shophouses are built as a row of 8-10 units with 3-5 storeys in height. Each unit is 4 m. in width and 12 m. in length with a 2-m. open space at the rear (Fig. 1). However, being use as various functions does not mean it is a good flexible building. For the Bangkok mixed-use promotion, degree of adaptability and flexibility is a major concern. Nonetheless, the shophouses are not designed for an adaptive building. Residents generally change, repair, and renovate them as they pleased within the given structure, even law mutiny. Without the experienced builders or contractors, the residents have difficulties to do these by themselves and pay a high renovation cost. To encourage adaptability, the support-infill can increase possibilities of flexibility. Therefore, the study of a shophouse support is proposed (Tirapas & Suzuki, 2013). This results from the survey of 70 existing shophouses in Bangkok abided by typological study (Habraken, 1988) and Open Building concept (Kendall & Teicher, 2000). This study aims to evaluate the proposed shophouse support in order to investigate its capability and potential in developing for future application in Thailand. Therefore, the study evaluates the designers’ attitudes toward the support-infill concept, the method of using support for aiding a variation design, finally, the quality of the proposed shophouse “support”. The evaluated method is conducted with 35 Thai architects accompanied by individual layout designs and questionnaires after the test. 2. Flexible Shophouse Building 2.1 Building Flexibility In order to promote mixed-use development in Bangkok, the flexible building is one of the keys. Israelsson and Hansson (2009) state the two major influences which promote building flexibility: flexibility factors and decision-makers. The flexibility factors are awareness of stakeholders, finance, installation, future planning, production (manufacturing), and material standard. The decision-makers are those involved in building industry: property owners, architects, contractors, authorities, project manager, users, and clients. The decision-makers are also a significant impact on the degree of the flexible building. The flexibility factors reveal what issues should be focused and paid attention to. According to the flexibility factors, the flexibility awareness is that the decision-makers recognize the level of the potential of adaptability and change of a building. The future planning is to consider all possible functions which can be changed in the future. This synchronizes with the concept of Open Building. Thus, flexibility acknowledgement, future planning, decision-makers, are main focused subjects of this study. Generally, the shophouses are simple buildings which mainly aim for investment benefits. The conventional design and construction process of the shophouses mainly respond to predestined activities and exclude end-users to be participated. The developers, architects, engineers, and contractors are the main players in deciding of the shophouses’ form, structure, and systems. The problem of how the shophouse design consents all decision-makers to participate in the design process can be encouraged by a systematic design and structure with participation permission. This not only increases participation of decision-makers in the design process, but also encourages awareness flexibility of stakeholders which increase efficiency of adaptation and adjustability of the building. 2.2 Open Building Open Building aims at increasing a capacity of building in terms of efficiency use, business benefit, marketing, construction method and product technology, social and individual living quality, and sustainability. The idea is to design an overall building to accommodate changes from different building users or end users which is based on the level of control of various parties involving in construction and building industry over the physical environments (Kendall and Teicher, 2000). Moreover, the idea distinguishes a separation between urban, building, and infill level which make possible for changes in each level without any interruption. This study, therefore, emphasizes on the building level: support level. On the support level, the architects, interior designers, contractors, mechanical and systematic engineers are the main decision-makers whose decisions are based on the building functions, stability, and aesthetics. On the infill level, the objects within a unit are controlled over by the residents or users who can move, relocate, or replace all those objects as they are pleased with no effect in the support level. In order to apply the idea, the support and infill should be physically separated. Therefore, the building structure and building systems cannot be a single assembly but unwind between the support and infill. The Open Building has a possibility to be practiced and applied in the Bangkok shophouses. Fig. 1 The Bangkok Shophouses on the Fig. 2 The Proposed Bangkok Support: The Bold Bangkok Streets. (photo by: author) Grid - 30x30 cm; Light - Grid 10x10 cm. (Tirapas & Suzuki, 2013). 2.3 Design of Bangkok Shophouse Support According to the previous study (Tirapas & Suzuki, 2013), the shophouse support design was based on the survey of the 70 existing Bangkok shophouses via questionnaires and typological study abided by John Habraken (1988). The 7 districts were selected based on the demographical data and Bangkok land use map of 2006. Next, 10 random shophouses from each district were focused for the typological study and analysis. The support design process is adhered by Habraken (1981). The process creates a series of problems to generate the support. These problems are zoning analysis, sector analysis, basic variations, and sub-variations. To accomplish the shophouse support, basic information of zones and margins of support must be addressed, especially, their positions and dimensions. As a result, the shophouse support is proposed and presented in Fig. 2. The proposed shophouse support has added two major elements: vertical shafts and stairs positions. There are 2 vertical shafts located in the alpha zone at the back side and alpha-beta margin at the front. The back vertical shaft is actually at the back of the shophouse before extension. The front vertical shaft is provided for a possible opportunity for service functions. These offer opportunities for the service functions to serve various activities in the shophouses. The normal practical size of service shaft, 30 x 60 cm, is applied as service shaft. Moreover, the stairs position zone is also addressed. The stairs, for the residents, is more comfortable to adjust than other building structures (Tirapas & Suzuki, 2013). As a result, the stairs position zone is located on the opposite side of the vertical shaft which is also defined as a circulation zone perpendicularly with the zones and margins (Fig. 2). According to Habraken (1981), a support can be evaluated via 3 main characters: (1) possible for various layouts; (2) possible for changes or increases of use within a support; (3) possible for different function adaptations. The first character is to examine alternative layout possibilities within a support. The second is to measure possibilities to extend or adjust functions. The last one is to estimate possibilities of future change of programs. As a result, the shophouse support is evaluated its efficiency according to these criteria. 3. Method of Bangkok Shophouse Evaluation 3.1 Overall Method The method of the support evaluation is conducted into two procedures. The first step is the voluntary test. A group of 35 Thai architects is required to design a free choice of layout on the shophouse support for a mix of business and residence of their own families, friends, or relatives, etc. The design conditions are a typical unit of the shophouse support (support plan) with 3 m. of floor – floor structure and 3 1/2 storeys in height (excluding roof terrace). The second step is the questionnaires. The architects are also required to write evaluations based on their understanding of the Support-Infill concept, the method of design layout, and the support evaluation. Finally, the results from both design layouts and questionnaires are analyzed and concluded for recommended directions for the proposed support improvement. Even though, it is the voluntary process, the voluntary architects are selected via a set of criteria. All of them have at least 2-year design experiences with various backgrounds: designing a new shophouse project, renovating shophouse project, renovating other project rather than shophouse project, and/or none of them (Fig. 5 and Fig. 7). 3.2 Method of Design Layout on the Shophouse Support In order to design layout on the proposed support, the method of design guideline is also given. The first step is the architects must select the functions from the given list on Table 1. Next, they must check their selected functions with the Table 2 whether what purpose of space of the selected functions are. Later, Table 3 and Fig. 3 identify the possible locations of each function on zones and margins on the proposed support (Fig. 2) (Tirapas & Suzuki, 2013). Table 1 List of Functions (Based on “Variations: The Systematic Design of Supports”) Abb. Abb. Names of Space Names of Space Name Name SH Shop activities K1 Kitchen for cooking only L1 Living room without dinning function K2 Eat-in kitchen L2 Living room with dinning function L3 S Siting room Second living room SD Study room B1 One-person bedroom P B2 Two-person bedroom ST Storage B3 Master bedroom BA Bathroom OP Open to below WK Working office LD Laundry area/drying cloth area Playroom Table 2 Relationship between Functions and Purposes of Space General Purpose Space SH S P L1 L2 L3 OP WK LD Special Purpose Space SD K1 K2 B1 B2 B3 OP WK LD Service Space BA ST - - - - OP - LD Table 3 Relationship between Positions and Purposes of Space (Habraken, 1981, reproduced) Position Position Position I II III General Purpose ● ● Special Purpose ● Service Purpose ● ● Fig. 3 Example of Positions of Purpose Spaces. (Habraken, 1981). 4. Evaluation Results 4.1 The Voluntary Architects Information As shown in Fig. 4, the basic information of the voluntary architects is 21 male (60%) and 14 female (40%). Fig. 5 shows the professional experience ranges which are 2-4 years, 12 persons (34.29%); 4-6 years, 4 persons (11.43%), 6-8 years, 6 persons (17.14%), 8-10 years, 1 person (2.86%), and more than 10 years, 12 persons (34.29%). Fig. 6 shows the age of the architects which are 21-30 year-old, 13 persons (37.14%); 31-40 year-old, 20 persons (57.14%); 41-50 year-old, 2 persons (5.71%). Fig. 7 shows the various experiences of the voluntary architects in shophouse design, building renovation, and Support and Infill experience. Seventeen architects have designed new shophouse projects (48.57%). Twenty three architects have shophouse renovation experiences (65.71%). Twenty two architects have other building renovation experiences (62.86%). Four architects have none of these design experiences (11.43%). Six architects have experiences of the Support-Infill concept (17.14%). Fig. 4 Basic Information of the Voluntary Architects Fig. 5 Shophouse Renovation Experiences of Voluntary Architects Fig. 6 Age of the Voluntary Architects Fig. 7 Shophouse Renovation Experiences of Voluntary Architects 4.2 Questionnaire Results 1) Former Concept of Renovation and Problems Moreover, the study tries to identify the key ideas and concerned issues in their general renovations. Based on the answers to the questionnaire, the general renovations ideas and issues are: new residential need responses, minimum effect on the existing structures, functional efficiency, new conditions of use, regulations, new image of the renovated building, lighting and ventilation, and existing service systems. The reasons for their concerns are to achieve the ultimate uses and meet the controlled budget, livable atmosphere, and safety of the users. According to the renovation problems, the issues are conditions of the existing structures and service systems, strength of the existing structures, regulation permissions to change or add old and new structural elements and functions, and error documentations of the existing conditions. The reasons are that the existing structures limit the possibilities to suit the new programs and may be difficult to resist loads of the new programs. The renovation budget is also a major concern. Most importantly, the safety also limits the existing structural changes as well. The normal ideas for the renovation are open plan, flexibility, modular system, light weight structure, moveable elements or partitions. The main reason is that these concepts create multiuse within a space and comfortable to manage both spaces and operations. The details of connections and materials are convenient to adjust. Other reasons are cost efficiency and fast construction. The former concept of renovation has presented that the important concerns are the needs of the users, the conditions of the structures and service systems, the regulation limitations, and the safety of the users after the renovation. All these are the key issues affecting the renovation concept selection of the architects. Unfortunately, none applies the flexibility of the building or the future changes, unless the clients or users demand. This reflects that the adaptable building is not a priority, although changes are common to happen. Fig. 8 Understanding of Support and Flexible Building Design Application Fig. 9 Possibilities of Applying Support-Infill 2) Support-Infill Understanding and Flexible Design Concept Implementation The questions inquire the voluntary architects of their understanding of the support-infill concept. The questionnaire includes a brief the support-infill concept which allows them to inspect and evaluate the initial conceptual understanding. Fig. 8 shows that three persons do not understand the concept (8.57%). One person rarely understands (2.86%). Thirteen persons fairly understand (37.14%). Eleven persons strongly understand (31.43%). Seven persons clearly understand (20.00%). According to the questionnaire results, many people understand the concept as they have renovation experiences. However, there are unclear of the concept applications and infill components; for examples, which building structural elements can be supportive or infill elements; old or new buildings in which the concept can be applied. A few architects can distinguish the characteristics between the precast and support-infill system. Furthermore, there are also various degrees of agreement on applying the flexibility concept in the building design. From Fig. 8, none disagrees and rarely disagrees with applying the support-infill concept. Five persons fairly agree (14.29%). Eight persons strongly agree (22.86%). Lastly, twenty two persons strongly agree in applying the idea (62.86%). Mostly designers agree to implement the flexibility idea in the design. The positive responses of the application of flexibility concept in building design are mostly based on the economic benefits: worthy investment, cost efficiency, reuse structures and materials. They also recognize that the concept can serve diverse needs and changes of use by the users. Expanding to a multiuse building is also a positive aspect of the idea. The interesting aspect is its social response. Its flexibility concept suits well with the expanded family in Thai society. This can be a potential marketing for a new alternative housing for the clients and developments. 3) Support-Infill Application Possibility To see possibilities in applying the support-infill concept in building design, the questions ask whether the designers see possibilities in applying the ideas to shophouses, other building types, and building industry in Thailand (Fig. 9). The results show that, in applying in shophouses, none thinks it is impossible. Four persons think it is hardly possible (11.43%). Five persons think it is fairly possible (14.29%), twenty persons think it is strongly possible (57.14%). Finally, six persons think it is very positively possible (17.14%). The comments of the positive application are a new tendency of renting a space in high price in business areas, many real examples of renovation (not support-infill concept), modular-like and repetition structure, many shared elements and spaces in shophouses, responding to expanded family culture, and new alternative for housing development. The negative responses are ambiguously understand of the concept, regulation limitations (changing building use), existing structure problems, limited space arrangement from the proposed support (zones and margins). In applying the idea to the other building types, none thinks it is impossible. One person thinks it is rarely possible (2.86%). Fifteen persons think it is moderately possible (42.86%). Sixteen persons think it is strongly possible (45.71%). Three persons think it is the most possible to apply (8.57%). The supportive comments are it is possible for those frequently changed buildings, urban regulation allowances, and low cost of renovation. Even though there are fairly high numbers for implementing the concept to other buildings, some concerns are also strongly addressed as well. Those concerns are complexity of building systems and structures which will cause difficulty in renovation. The strength of structure is also a safety concern for new functions. There are also different design criteria in applying to complex buildings which may contradict with the concept. Furthermore, the question asks what other building types which the idea can possible be implied. The suggestions are divided into 3 groups: large span building (factory, exhibition hall, and shopping mall), structural repetition building (office, highrise office, gated housing community, and mass housing), and small scale housing (shophouses and townhouses). In applying the idea in the building industry, two persons think it is impossible (5.71%). One person infrequently realizes the possible. Eight persons think it is rather possible (22.86%). Eleven persons think that it is strongly possible. Finally, thirteen persons greatly see possibilities in applying the concept (37.14%) (Fig. 9). Most of the positive implementations result from economic aspects. As it can be produced as mass products; therefore, it reduces both building investment and construction period. The flexibility is a new key issue for the future building marketing as the diverse needs of users; therefore, it is possible for the manufacturers to respond to this emergent market. Some of the comments address the problems of inadequate labor in constructions, therefore, precast system, prefabrication, or unrequired skill works are highly recommended. However, the important comment is the effect of design freedoms of the architects. In addition, the changes of design and construction industries may impact on industrial investment as a whole; thus the implementation in the building industry could be gradually changed. With different degrees of the concept implementation, the results show highly possibilities in all the subjects. The highest possibility is in the shophouses. There are positive opportunities in the other building types, the ranges still weigh on fairly and strongly possibility. 4) Method and Procedure of Layout Design of the Shophouse Support The proposed method (design tool) and procedure are also tested. The issues are degrees of convenience in using the procedure and design tool in reality, and how they guide the design for better alternatives. As shown in Fig. 10, the results illustrate that none realizes this method as inconvenience. Nine persons state that the procedure is rarely difficult to use (25.71%). Thirteen persons both in fairly and strongly employ the method (37.14%). None states the method is very convenient for design practice. Many architects mention that the procedure and design tool are beneficial and practical, especially, the guideline, and zones and margins. It also decreases time consuming during the design. However, the main restrictions are the design limitation by the zones and margins, and difficult to understand the procedure. This is because the technical terms and the idea are rather new. The suggestions for improvement are not only the designers but also general people. The method should use an easy-to-understand tool; for instance, computer 3D and diagrams. Most importantly, the education of the idea and method are recommended. Fig. 10 Degrees of Convenience and Aid Design Layout Fig. 11 Three Criteria of Support Evaluation As shown in Fig. 10, in term of aiding the layout design, none states the method is useless. Four persons state that the method is rarely helpful (11.43%). Thirteen persons express that it is fairly useful tool (37.14%). Fourteen persons utter that the method is useful and helpful for a convenient layout design (40.00%). Four persons affirm that the method and procedure are very supportive in the design the layout (11.43%). The positive comments are the good systematic procedure and tool, addressing a direction for planning, offering alternative for the design, suitable for the shophouse design, faster design, and making planning easier. The negative comments mainly are limitations of creativity and other related issues in design such as budget, regulations, participation, etc. The suggestions to develop the method are legislative integration in the shophouse support, case study, and a support for vertical extension. 5) Support Evolution According to the 3 quality criteria by Habraken, the results are presented in Fig. 11. First is planning diversity, two persons disagree with the diversity advantages (5.71%). Nine persons express that it occasionally and strongly promotes planning variations (25.71%). Eleven persons state that it moderately fosters the issue (31.43%). Four persons greatly agree that the support encourages planning variations (11.43%). The zones and margins are the most constraint for the creativity and variety. As the zones and margins are fixed, it is most likely that the functions are predetermined as well. Another comment is the shape and form of the shophouse itself which restrict the creativity and variations. Even though zones and margins roughly guide the functions, adjustments will occur eventually. There are still potentials for employ the concept; conversely, a new zones and margin can be redesigned and reintroduced. In term of space extension, two persons disagree with its extendable within the support (5.71%). Four persons utter that it is hardly to expand. Eleven persons both reasonably and intensely agree that support is expandable (31.43%). Finally, seven persons extremely visualize the potential of the extendable of the support (20.00%). The architects fairly agree that the extension is possible within the support. In order to encourage this potential of the support, the infill system must be addressed more clearly. In addition, the floor system and materials should be suggested for a vertical extension within the support. The vertical extension aspect will also increase creativity and variations as well. For functional conversion, none expresses that the support is both useless and infrequently convertible. Seven persons state that it is acceptably adaptable (20.00%). Nine persons strongly accept its changeable potentials (25.51%). Finally, nineteen persons tremendously agree that the support can fully serve new uses if changes are needed (54.29%). This flexible and convertible use is the strongest potential of the shophouse among the 3 criteria and also common acknowledge in the building industry. In order to promote the functional conversion aspect, more details and elements of the support are required to be reconsidered; for example, lift zone (in case of infill) or lift location (as support) in the support. 6) The Problem of Support-Infill Concept Implementation The questionnaire also inquires the architects to consider the problematic issues of Support-Infill application. There are 3 main issues: prefabrication construction, interests of manufacturers, infill system (Fig. 12). The question inquires whether prefabrication construction is uncommon in practice; five persons strongly disagree and disagree with the idea (14.29%). Eight persons fairly agree that prefabrication system is fairly uncommon practice (22.86%). Ten persons strongly agree that it is uncommon practice (28.57%). Four persons greatly agree that it is uncommon practice (11.43%). There are 3 unanswered persons. The most comment causing its uncommon practice is mostly based on its high construction cost, a lack of knowledge of both clients and architects, and lack of skill labor. The suggestion mostly focuses on increasing the knowledge of this construction technique. The second question regards whether the manufacturer is uninterested in developing of infill system. Three persons strongly disagree with the idea (8.57%). Four persons disagree (11.43%). Eleven persons fairly agree that the manufacturer is uninterested in developing the infill system (31.43%). Ten persons strongly agree (28.57%) and four persons significantly agree (11.43%) that the infill system is now developing in the marketing. There are also 3 unanswered persons. In general, the infill system is still less developed in the Thai building construction. The main reasons are unpopular in the market which causing the high production price and high cost of investment. Another reason is the unfamiliarity of clients and architects. To encourage the interests of the manufacturers, the suggestions are to promote the prefabrication and infill system for marketing and improve their details for comfortable applications. The third question regards whether the infill system is unpractical and unease for the users. Two Fig. 12 Issues of Applying Support-Infill in Construction Industry persons strongly disagree with the idea (5.71%). Four persons support that the infill system is practical and convenient for the users (11.43%). Seven persons fairly agree with the idea (20.00%). Eight persons strongly agree (22.86) and thirteen persons greatly agree (37.14%) that infill system is uncomfortable for use. There is 1 unanswered person. The infill system is still uncommon and unpractical. General comments are the high cost and unpopular in the market. An interesting comment is that Thai people is unfamiliar with the Do It Yourself concept. This leads to the suggestions that there should be technicians, and simple details and tools to assist its assembly. 5. Conclusion The proposed shophouse support is positively accepted. It can be divided the concept implementation into two parts: flexibility and support-infill. Firstly, the architects are highly interested in employing the flexible idea. However, the main concerns are to achieve the ultimate uses of the users, to meet the budget, the livable atmosphere, and the users’ safety. In addition, the flexibility itself is not their priority. This could result from the common practice which always design based on pre-determined functions, not possible functions. Secondly, the support-infill concept is highly recommended, especially, in the shophouses. These result from the reducing renovation investment, reusing of the building potentials, and responding to a new life style, culture, and new building marketing approach. In contrast, it is also difficult to implement the concept. The main reasons are unclear of the concept in practice; complex building conditions, regulation control, and safety after renovation. For procedure and method, the proposed shophouse support is a practical and systematic guide for the planning. However, the problematic is a constraint of the design creativity and regulation restriction. The recommendations are to apply the graphic communication, educational system, and regulation integration in the support design for understanding the concept and open opportunities for its applications. Overall, the proposed shophouse support quality is accepted. The convertibility is the best quality of the support; while the creativity and variation are the most problematic issues. The zones and margins are the most difficulty in encouraging the creativity and diversity. The functional extension is relied on the infill system provision. Floor structure is also important for the vertical extension. It requires more criteria to design a better support; for example, renovation regulations and decision-makers participation, etc. It is also important to conduct a test of the shophouse support with shophouse residents. The prefabrication and infill system are unpopular in Thai construction due to high cost and few return investment, lacks of marketing promotion, lack of technicians, and unclear understanding of its application. In encouraging the Support-Infill in construction, these issues should be improved. The initial ideas are promoting the idea in institutes and construction markets, and training the skill technicians. Implementation of the building flexibility also reflects the flexible factors mentioned by Israelsson and Hansson (2009). The architects express the similar flexible factors; however, building renovation regulations are also often addressed in their concerns. This could be also another flexible factor in building flexibility of the shophouses and other buildings. Although, the flexibility is an interesting concept and possible application, the acknowledgement of the flexible building is less recognized for the designers. This can be evinced in the designers’ concerns regarding to the method of renovation and functional design approach in the shophouse support. Furthermore, the flexible, open for variation, and unpredictable use building are still insignificant keys of the design principles and city developments. Thus, increasing the flexibility acknowledgement and open functional design are the important aspects to promote the flexible building support and design. 6. Citation & Reference Habreken, NJ. (1981). Variations: the systematic design of supports, trans. Wiewel, W., & Gibbons, S. (ed.), Massachusatts: MIT Press. --- (1988). Type as a social agreement. Asian Congress of Architects. Seoul. Israelsson, N. & Hansson, B. (2009). 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