sustainability

Article Study on Courtyard Residence and Cultural Sustainability: Reading Chinese Traditional Siheyuan through Space Syntax

Bo-Xun Huang 1,2,*, Shang-Chia Chiou 1 and Wen-Ying Li 1,3 1 Graduate School of Design, National Yunlin University of Science and Technology, Yunlin 64002, Taiwan; [email protected] (S.-C.C.); [email protected] (W.-Y.L.) 2 College of Arts College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou 350118, China 3 College of Architecture and Urban Planning, Fujian University of Technology, Fuzhou 350118, China * Correspondence: [email protected]



Received: 13 February 2019; Accepted: 12 March 2019; Published: 15 March 2019


Abstract: The United Nations and local governments have supported a four-point sustainable development framework, including environmental responsibility, economic viability, social equity, and cultural vitality. This study is based on the theoretical framework of sustainability to study the traditional Chinese siheyuan residence. Space syntax attempts to explain how spatial structures express social or cultural significance, such as the hierarchical relationship and privacy in it. The main purposes of this study are: (1) To analyze the spatial topological layout of traditional siheyuans by using the space syntax theory, and thus deduce the cultural connotation embedded in traditional siheyuans; (2) to compare and analyze the spatial morphology and behavior patterns of traditional and modern houses; (3) to explore how to integrate courtyard features into contemporary design and promote cultural sustainability. This study expounds the concept and application of syntactic analysis, and the relationship between the syntactic attributes of specific buildings in a particular area, and the culture and life of the local people within that area. As time goes by, the spatial form of houses has changed. However, in terms of spatial allocation index, the significant difference between traditional residences and modern residences lies in the integration and equivalence of all spaces in residences. We can learn from the cultural values of traditional siheyuans, meaning “people-oriented”, to rationally design modern residences with cultural connotations.

Keywords: traditional siheyuan; cultural sustainability; space syntax

1. Introduction The courtyard house is a kind of family residence with a long history. The main space of the building, which is arranged around the central courtyard, is one of the oldest residence types in the world. It can be traced back to 5000 years ago, when it was built in the Middle East and China [1]. The courtyard house occupies an important position in architectural history, and only in the past few centuries did architects ignore its use. Recently, more attention has been paid to the courtyard housing type to solve some of the inherent problems of dense inner-city housing. As cities face the challenges of rapid modernization and urbanization in the new era, the traditional courtyard residence is disappearing. In response to the international metropolitan environment, city planners and scholars are working hard to protect this important element of the Chinese cultural heritage [2]. Some researchers have studied the influence of social and cultural factors on traditional Chinese courtyards, according to professional knowledge [3–6]. D. Zhang introduced the interaction of nature, culture, and architecture, and proposed the concept of culturally-sustainable architecture [5].

Sustainability 2019, 11, 1582; doi:10.3390/su11061582 www.mdpi.com/journal/sustainability Sustainability 2019, 11, 1582 2 of 15

She proposed four major themes from Chinese philosophy, including harmony with heaven, harmony with earth, harmony with people, and harmony with oneself, as well as the physics of Aristotle (384–322 B.C.), the Greek philosopher: Form, space, matter, and time. She used this innovative architectural and social science method as the standard to evaluate the newly built and renovated siheyuan residential projects in China since the 1990s, and examined the political, economic, cultural, social, and spatial factors affecting cultural sustainability [6]. The focus of this study is not on individuals or the individual forms shown in scattered courtyards, but on genotypes with universal significance. It is to study how traditional courtyards endow profound social and cultural connotations with forms through their special spatial and organizational patterns; to study the spatial form of courtyards and the interaction between social and cultural factors within; to understand how courtyard culture enters the material entity and form of courtyards through space configuration; and finally, to discuss the sustainable development of the cultural heritage of siheyuan. This paper takes space syntax as the main research method and proves it by field investigation. Space syntax, in its simple form, is based on the theme that human society has complete space information, space environment or residence space, and embedded social information. This theme transforms the analysis method of architectural environment study from the popular trend of aesthetic visual analysis, to a complex quantitative method, which employs numerical analysis to quantify space properties, and extracts cultural information from siheyuan through mathematical models. Social and cultural information describing the formation process is embedded in the spatial layout of each building. The study of space syntax has developed useful tools to collect such information, outlined the social logic behind the spatial layout of buildings, and analyzed their values.

2. Literature Review The Chinese have been living in siheyuan-style houses for thousands of years. To date, the earliest siheyuans discovered by archaeologists were built in the middle of the Neolithic Age, as represented by Yangshao Culture (5000–3000 B.C.) [7]. The ancient Chinese preferred this type of residence because the fences helped to protect the privacy of the family to the maximum extent, as well as to prevent wind, noise, dust, and other threats. The courtyard provides light, air and landscape, and also serves as a space for family activities when weather permits. A traditional Chinese siheyuan usually accommodates three or four generations of large families [6,8,9]. Scholars admit that sustainable development consists of four pillars: Environmental responsibility, economic viability, social equity, and cultural vitality. The root of the word “sustainability” is from the Latin sustinere (tenere, to hold; sus, up). Dictionaries provide more than 10 meanings for “sustain,” the main ones being to “maintain”, “support”, or “endure” [10,11]. How space works for people is not simply about the space itself, but about the relationship between all the spaces that make up a layout. The layout refers to a spatial pattern or configuration, implying the existing relationship [12]. Traditional Chinese architectural culture does not emphasize the independence of architecture, the core and essence of which is the architectural portfolio. The traditional siheyuan is a good reflection of such a portfolio, which produces a spatial relationship that conforms to the traditional order of life. Various writers, such as Darlow and Wheelwright have observed that sustainable development is to a large extent a cultural task because it seeks to change attitudes and lifestyles [13,14]. Judy Spokes, the executive officer of Cultural Development Networks, asserts that “culture is both overarching and underpinning” [15]. As such, Brand and Nurse believed that culture should be placed front and center of the sustainable development framework, and fully integrated into the other three pillars, as it is the basis for testing the meaning and practice of sustainable development [16,17]. Creative City Network of Canada likewise contends that “culture is a core dimension of vibrant and sustainable communities”, because the character of a place is inseparable from its traditions and culture, as they are lived and expressed in the activities and social life of the community [18]. Sustainability 2019, 11, 1582 3 of 15

It is necessary to increase the cultural dimension on the basis of environmental, social and economic dimensions, when we understand “sustainability”, because the unique role of cultural dimension in sustainable development has been paid more and more attention. The cultural dimension of sustainable development is not only the important power of social integration, but also environmental sustainability. In 2001, Australian scholar Jon Hawker took the lead in proposing four levels of sustainability: Cultural activities (well-being, creativity, diversity and innovation), social equality (justice, participation, cohesion and welfare), environmental responsibility (ecological balance) and economic ability (material prosperity). He believes that a sustainable society depends on a sustainable culture. Culture, as the fourth pole in the triple framework of sustainability, must be a separate and “unique” reference point [15]. Western scholars have different understandings of the role of cultural sustainability in the sustainable development system. Some scholars regard cultural sustainability as a separate dimension in the framework of sustainable development; some scholars regard it as an intermediary model that balances the relationship among the three pillars of the economy, the environment and society; and other scholars regard it as the overall social basis for achieving sustainable development [19]. Therefore, the reason as to why cultural sustainability is one of the important characteristics of the city is that it is not only the driving force for urban civilization, but also the lifeblood of the city’s vitality, and the source of sustainable urban development [20], based on its basic connotation. For the development of contemporary Chinese cities, traditional buildings and neighborhoods, urban environment and biodiversity have been damaged to varying degrees, with rapid urbanization and large-scale development and construction, which will not only affect the healthy development of urban culture, but also restrict the ecological and social sustainability of the city. Siheyuan, a traditional Chinese courtyard building with a long history, is an extremely important historical and cultural heritage. The urban structure of traditional courtyard buildings varies according to local development processes and policies. This unique spatial order and organization in these regions reflects the local historical environment and cultural characteristics. The public courtyard in the siheyuan promotes social interaction, and the private courtyard promotes self-cultivation. The relationship of the neighborhood is influenced by two factors: One is the form and space of the courtyard house, and the other is the background of a changing society, socio-economic differences, residence periods, modern lifestyles, community participation, common language, cultural awareness and residents’ culture [21]. The public courtyard helps to maintain some traditional Chinese cultural activities. The main function of the public courtyard is to maintain communication and interaction between people and people, as well as people and nature. However, many cultural activities are rarely or no longer involved in public courtyards due to factors such as time, climate, ownership, size and the facilities of the courtyard. We should protect and inherit the traditional courtyard and its culture.

3. Research Method Space syntax is a term that appeared in the 1970s, and it is used to describe the theory and technology related to space and social relations [22,23]. Space syntax analysis uses the concept of “graph theory” to express geographic space, and the research hypothesis believes that the interaction between human and environment is influenced by the space organization structure. “Graph theory” is also known as “topology”, which expresses the concepts of “space” and “logic” with a structure that consists of “points” and “lines”. The focus of this study is on the structure (connection) relationship between points and lines, not on distance nor direction. In the space syntax, the understanding and generalization of space includes the following analysis systems: (1) Convex space analysis. Through this rule, the actual building space can be translated into a system consisting of convex spaces. (2) Axial line analysis. In this system, elements are linear when the subject of study is movement [24]. (3) Visibility graph analysis: Including single isovists and isovist fields: Visibility graph analysis is utilized in cases where the subject of study shows complicated behavior patterns [24]. Underlying Sustainability 2019, 11, x FOR PEER REVIEW 4 of 15 Sustainability 2019, 11, x FOR PEER REVIEW 4 of 15 (2) Axial line analysis. In this system, elements are linear when the subject of study is movement (2) Axial line analysis. In this system, elements are linear when the subject of study is movement [24]. [24]. Sustainability(3) Visibility2019 ,graph11, 1582 analysis: Including single isovists and isovist fields: Visibility graph analysis4 of 15is (3) Visibility graph analysis: Including single isovists and isovist fields: Visibility graph analysis is utilized in cases where the subject of study shows complicated behavior patterns [24]. utilized in cases where the subject of study shows complicated behavior patterns [24]. Underlying this analysis are fields of view that are visible from a particular point. Therefore, Underlyingthis analysis this are analysis fields of are view fields that of are view visible that from are avisible particular from point.a particular Therefore, point. this Therefore, analysis this analysis model is based on the reflection of light, and determines the patterns of the thismodel analysis is based model on the is reflection based on of the light, reflectio and determinesn of light, the and patterns determines of the motionalthe patterns behavior of the of motional behavior of people in the environment [25–31]. motionalpeople in behavior the environment of people [25 in– 31the]. environment [25–31]. This study mainly uses Convex Map for modeling analysis. When dealing with social This studystudy mainly mainly uses uses Convex Convex Map forMap modeling for modeling analysis. analysis. When dealing When with dealing social interactions,with social interactions, spaces are convex [24]. Convex spaces are analyzed from two aspects: (a) Spaces spacesinteractions, are convex spaces [24 ].are Convex convex spaces [24]. areConvex analyzed spaces from are two analyzed aspects: (a)from Spaces two exhibitingaspects: (a) non-linear Spaces exhibiting non-linear behavior and the (b) buildings and common spaces among them, as well as the exhibiting non-linear behavior and the (b) buildings and common spaces among them, as well as the behaviorinterior arrangement and the (b)buildings of housesand [27,32]. common The systematic spaces among analysis them, process as well of as convex the interior space arrangementis illustrated interior arrangement of houses [27,32]. The systematic analysis process of convex space is illustrated ofwith houses a simple [27,32 diagram]. The systematic (Figure 1). analysis process of convex space is illustrated with a simple diagram (Figurewith a simple1). diagram (Figure 1).

(a) (b) (c) (a) (b) (c) Figure 1. Convex map transformation process diagram: (a) Original building space; (b)Convex Map; Figure 1. Convex map transformation process diagram:diagram: (a)) OriginalOriginal buildingbuilding space;space; ((bb))Convex Convex Map; Map; (c)Topological relations. (c))Topological Topological relations. relations.

4. Study Process 4. Study Process 4.1. Traditional ChineseChinese SiheyuanSiheyuan 4.1. Traditional Chinese Siheyuan Figure2 2 shows shows a bird’sa bird’s eye eye view view of theof the traditional traditional Chinese Chinese three-entrance three-entrance siheyuan. siheyuan. In this In type, this Figure 2 shows a bird’s eye view of the traditional Chinese three-entrance siheyuan. In this thetype, southern the southern external external courtyard courtyard is located is located next next to the to entrancethe entrance court. court. Rooms Rooms on theon the south south side side of type, the southern external courtyard is located next to the entrance court. Rooms on the south side theof the external external courtyard courtyard are adjacentare adjacent to the to street, the street, and used and as used housing as housing for male for servants, male aservants, reception a of the external courtyard are adjacent to the street, and used as housing for male servants, a areareception for guests, area for or forguests, classrooms or for whereclassrooms private wher tutorse private taught youngtutors memberstaught young of the members owner’s family.of the reception area for guests, or for classrooms where private tutors taught young members of the Afterowner’s passing family. through After passing the well-decorated through the gate, well-decor the middleated orgate, inner the courtyard middle or is inner the focal courtyard point ofis the owner’s family. After passing through the well-decorated gate, the middle or inner courtyard is the complex.focal point The of middle the complex. room in The the northernmiddle room wing ofin thetheinner northern courtyard wing isof a prestigiousthe inner courtyard unit occupied is a focal point of the complex. The middle room in the northern wing of the inner courtyard is a byprestigious the leader unit of theoccupied family. by This the middleleader of room the hasfamily. the mostThis beautifulmiddle room decorations has the andmost ornaments beautiful prestigious unit occupied by the leader of the family. This middle room has the most beautiful madedecorations with costly and ornaments materials. made The person with costly of secondary materials. importance The person in theof secondary family uses importance the rooms in the decorations and ornaments made with costly materials. The person of secondary importance in the eastfamily wing. uses By the the rooms same in token, the east the wing. rooms By in the westsame wingtoken, are the for rooms the third-ranking in the west wing family are member. for the family uses the rooms in the east wing. By the same token, the rooms in the west wing are for the Thethird-ranking northern courtyard family member. of the complex The northern is the backcourtyard court, of which the complex is the least is important,the back court, private which in nature, is the third-ranking family member. The northern courtyard of the complex is the back court, which is the occupiedleast important, by daughters, private femalein nature, servants, occupied and/or by daug usedhters, as a storage female area.servants, Rooms and/or in this used court as area storage called least important, private in nature, occupied by daughters, female servants, and/or used as a storage Houarea. ZhaoRooms Fang in this (back-coop court are rooms) called [Hou2]. Zhao Fang (back-coop rooms) [2]. area. Rooms in this court are called Hou Zhao Fang (back-coop rooms) [2].

Figure 2. A Bird’s Eye View of Traditional Siheyuan [2]. Sustainability 2019, 11, x FOR PEER REVIEW 5 of 15

Figure 2. A Bird’s Eye View of Traditional Siheyuan [2]. Sustainability 2019, 11, 1582 5 of 15 Literature shows that rich cultural information is embedded in the formation of this traditional house, which also reflects the influence of Chinese traditional cultural philosophy that “men work Literature shows that rich cultural information is embedded in the formation of this traditional outside, and women take care of the home”. The formation of the overall architectural layout shows house, which also reflects the influence of Chinese traditional cultural philosophy that “men work that its spatial order has a certain cultural significance. outside, and women take care of the home”. The formation of the overall architectural layout shows It can be said that it is a Chinese tradition that, where there is a house there is a courtyard. that its spatial order has a certain cultural significance. People regard houses and courtyards as an inseparable whole. This tradition has been going on for It can be said that it is a Chinese tradition that, where there is a house there is a courtyard. thousands of years, thus, forming a typical residential type—siheyuan. The biggest characteristic of People regard houses and courtyards as an inseparable whole. This tradition has been going on for this residential mode is that it centers on the space courtyard and allocates residential buildings thousands of years, thus, forming a typical residential type—siheyuan. The biggest characteristic of this around it, thus, forming an inward and enclosed courtyard. The basic principle followed by garden residential mode is that it centers on the space courtyard and allocates residential buildings around it, architecture is that, while it originates from nature, it is higher than nature, and tries to combine thus, forming an inward and enclosed courtyard. The basic principle followed by garden architecture artificial beauty with natural beauty. The expressed interest can be summarized by “poetic and is that, while it originates from nature, it is higher than nature, and tries to combine artificial beauty picturesque” [33]. with natural beauty. The expressed interest can be summarized by “poetic and picturesque” [33].

4.2.4.2. Analysis Analysis of of Building Building Layout Layout Relationship Relationship with with Space Space Syntax Syntax TraditionalTraditional architecture architecture is is chosen chosen to to describe describe syntactic syntactic analysis, analysis, as as the the traditional traditional architectural architectural layoutlayout contains contains strong strong cultural cultural information. information. TheThe layout layout of of traditional traditional Chinese Chinese architectural architectural space space is is deeply deeply influenced influenced by by traditional traditional Chinese Chinese culturalcultural thoughts. thoughts. Traditional Traditional cultural cultural thoughts thoughts can becan divided be divided according according to the philosophical to the philosophical system, meaningsystem, Confucianism,meaning Confucianism, Taoism, Mahayana Taoism, Mahayana Buddhism, Buddhism, and Neo-Confucianism and Neo-Confucianism from the Northern from the SongNorthern Dynasty Song to theDynasty Qing Dynasty.to the Qing Moreover, Dynasty. the More threeover, thoughts the three of “Yi”, thoughts “Li”, andof “Yi”, “Dao” “Li”, influence and “Dao” the traditionalinfluence Chinesethe traditional spatial Chinese conceptual spatial layout. conceptual Figure 3layout. embodies Figure the 3 concept embodies of “binarythe concept coexistence” of “binary incoexistence”The Book of Changes in The Book[34]. of Changes [34].

(a) (b)

FigureFigure 3. 3.Space Space organization organization map map of traditional of traditional siheyuan: siheyuan: (a) Original (a) Original architecture architecture plan; (b plan;) space (b) organizationspace organization map. map.

TheThe principle principle of of binary binary coexistence coexistence in in traditional traditional architecture architecture is is embodied embodied in in the the existence existence of of “intermediate“intermediate space”, space”, as as the the third third space space element, element, and and as as “indoor” “indoor” and and “outdoor” “outdoor” space space elements. elements. ThisThis paper paper uses uses Donald Donald Preziosi’s Preziosi’s method method of of mark mark analysis analysis to to illustrate illustrate the the coexistence coexistence relationship relationship ofof the the three three space space elements. elements. This This method method uses uses “O” “O” to to represent represent the the indoor indoor space, space, “C” “C” to to represent represent thethe outdoor outdoor space, space, “V” “V” to to represent represent the the intermediate intermediate space, space, and and “—” “—” to to represent represent the the circulation circulation relationshiprelationship between between spaces spaces [34 [34].]. TheThe change change of traditionalof traditional Chinese Chinese architectural architectu spaceral is space to merge is indoor,to merge outdoor, indoor, and intermediateoutdoor, and spaces,intermediate and make spaces, useof and the make different use “characteristics” of the different of “characteristics” these three spaces. of Thisthese change three givesspaces. users This rich, diverse, and profound space experience, rather than just to seek changes in indoor spaces. According to the principle of binary coexistence of traditional architectural space organization, and with a simple traditional architectural space as the space syntax illustration, we can easily Sustainability 2019, 11, x FOR PEER REVIEW 6 of 15 Sustainability 2019, 11, x FOR PEER REVIEW 6 of 15 change gives users rich, diverse, and profound space experience, rather than just to seek changes in changeindoor spaces.gives users rich, diverse, and profound space experience, rather than just to seek changes in According to the principle of binary coexistence of traditional architectural space organization, Sustainabilityindoor spaces.2019, 11, 1582 6 of 15 and Accordingwith a simple to the traditional principle architecturalof binary coexistence space as of the traditional space syntax architectural illustration, space we organization, can easily andunderstand with a thesimple concepts traditional and terms architectural of space syntax,space as as the well space as the syntax relationship illustration, between we traditionalcan easily understandarchitectural the spaces. concepts We uniformlyand terms useof space Donald syntax, Preziosi’s as well method as the of relationship mark analysis, between which traditional assumes architecturalthat O is an indoorspaces. space,We uniformly C is an use outdoor Donald courtyard Preziosi’s space, method and ofV markis an analysis,intermediate which connecting assumes thatspace OO (Figure isis anan indoor indoor 4). space, space, C C is anis an outdoor outdoor courtyard courtyard space, space, and and V is anV is intermediate an intermediate connecting connecting space (Figurespace (Figure4). 4).

Figure 4. Analysis map of indoor, outdoor and intermediate space. Figure 4. AnalysisAnalysis map of indoor, outdooroutdoor and intermediate space. There are several possibilities for indoor, outdoor, and intermediate space organization. The spaceThere in the areare above severalseveral figure possibilities possibilities obviously for for does indoor, indoor, not outdoor, have outdoor, any and openings. and intermediate intermediate The following space space organization. figure organization. shows The spacethree The spaceindifferent the abovein thepossibilities figureabove obviouslyfigure of openingsobviously does notbetween does have not any spaces have openings. anyO, C,openings. Theand followingV. TheSpaces following figure are represented shows figure three shows as different blankthree possibilitiesdifferentpoints “O”, possibilities accesses of openings between of openings between them spaces betweenare represented O, spaces C, and asO, V. “—”, SpacesC, and and areV. each representedSpaces setting are can represented as be blank represented points as blank “O”,as a pointsaccessesgraph, “O”,called between accesses alignment them between graphs are represented them in terms are represented of as syntax “—”, andanalysis. as “—”, each Inand setting fact, each this can setting figure be represented can has be some represented advantages, as a graph, as a graph,calledmeaning alignment called it can alignment provide graphs ininformationgraphs terms in of terms syntax regardless of analysis. syntax of theanalysis. In fact,size thisor In relative figurefact, this has location figure some advantages,ofhas the some space advantages, meaning(Figure 5) it meaningcan[35,36]. provide it can information provide information regardless of regardless the size or of relative the size location or relative of the location space (Figureof the space5)[35 (Figure,36]. 5) [35,36].

(a) (b) (c) Figure 5. Relation analysis (a )map of indoor, outdoor(b) and intermediate space:(c) (a (a) Indoor or outdoor Figurespace cancan 5. beRelationbe accessedaccessed analysis through through map the the of “V” “V” indoor, intermediate intermediate outdoor space, space,and andintermediate and the the indoor indoor space: space space (a and) andIndoor outdoor outdoor or spaceoutdoor space are spacemutuallyare mutually can accessible.be accessedaccessible. The through The depths depths the of the“V” of three intermediatethe three spaces spaces are space, the are same. and the thesame (b) indoor In. this(b) In case,space this both andcase, theoutdoor both “O” the indoor space “O” arespaceindoor mutually and space the andaccessible. “C” outdoorthe “C” The spaceoutdoor depths can space onlyof the becan three accessed only spaces be throughaccessed are the the throug same “V”. intermediate h(b) the In “V” this intermediate case, space. both This the showsspace. “O” indoortheThis importance shows space the and ofimportance intermediatethe “C” outdoor of space;intermediate space in other can space; words,only bein the otheraccessed privacy words, throug of indoortheh privacythe space “V” ofandintermediate indoor outdoor space space space. and is Thishigheroutdoor shows than space the that is importance ofhigher (a). Thethan depthsof that intermediate of of (a). the The indoor deptspace;hs space inof theother and indoor outdoorwords, space the space andprivacy are outdoor higher of indoor space than thatarespace higher of and the outdoorintermediatethan that space of the space. is intermediate higher (c) The than situation thatspac ofe. (a).(c) is more The situationdept complicated;hs of is the more indoor the indoorcompli spacecated; space and musttheoutdoor indoor be accessedspace space are throughmust higher be thantheaccessed intermediate that ofthrough the intermediate space the intermediate and outdoor space. (c) spacespace The insituationand order. outdoor Outdoor is more space compli space in iscated;order. more theOutdoor important, indoor spacespace as it controlsmustis more be accessedindoorimportant, space through as andit controls intermediatethe intermediate indoor space,space space respectively.and interm and ediateou Comparedtdoor space, space withrespectively. in outdoororder. OutdoorCompared and intermediary space with outdooris space,more important,indoorand intermediary space as isit cleaner,controls space, quieter, indoor andspace more andis cleaner, mysterious. interm quieter,ediate space, and more respectively. mysterious. Compared with outdoor and intermediary space, indoor space is cleaner, quieter, and more mysterious. However, the above-mentioned space fully illustrates the application results of the principle of binaryHowever, coexistence: the above-mentioned(1) The spaces with space binary fully characteristics, illustrates the indoor indoorapplication “O” “O” and results outdoor of the “C”, principle coexist, of binaryand even coexistence: the traditional (1) The building spaces is with a space binary model characteristics, unit composed indoor of “O”the bi binaryandnary outdoor space combination. “C”, coexist, (2)and The even intermediary the traditional space building between is binary a space characteristics model unit composed inevitably exists,of the andbinary the space intermediary combination. space “V” even dominates the connection between indoor space and outdoor space in garden residences. Sustainability 2019, 11, 1582 7 of 15

(3) There are hierarchical relations in spaces; the locations and relations of spaces will affect the hierarchies of spaces. Next, this study quantifies the value of the depth relationship between spaces by using spatial syntactic operations.

4.3. Quantification Method of Space Syntax Social Logic of Space [36] proposed several concepts to analyze these settings in numerical terms, and this discussion focuses on these terms. The first term is “depth”, which calculates the number of spaces required to pass before reaching another space from a certain point. MD calculation can be expressed as [37]:

Total value of depth for all spaces from the root space MD= Total number of space in the graph−1

When MD is determined, the depth or shallowness of a space from a specific root point can be identified. When all spaces are directly connected to the root space, the depth has the lowest value, i.e., the system is shallowest, as shown in Settings (a) and (b). When spaces are connected in a linear sequence, the depth becomes the highest, with only one space directly connected to the root space, as shown in Setting (c). This study obtains the concept of relative asymmetry (RA) by comparing the space depth of a specific point with its theoretical depth or shallowness. Generally speaking, this process shows the concept of the integration of space and its system from a specific root point [33]. The calculation of RA adopts the following equation: The inverse concept of RA is integral. The high RA value of space indicates its low integration with the system, while a low value indicates its strong integration [35]. 2(MD−1) RA= Total number of space in the graph−2 The last term is related to the connectivity between a specific space and other spaces, which is called the control value (CV). Each space has a certain number (n) of direct neighbors; therefore, 1 each space gives its direct neighbors n . These numbers are added to measure the control value of each space, where high control values indicate high connectivity, and low control values indicate low connectivity of the space under consideration. Table1 describes the term and its meanings. According to the formula, the above examples (a), (b), and (c) are calculated, and the corresponding results (Figure6) are obtained.

Table 1. Explanation of the terminologies used in syntactical analysis.

Terminologies Higher Value Lower Value Depth Further away from the root space Nearer to the root space Mean Depth (MD) Deep space Shallow space Relative asymmetry (RA) Less integrated with the spaces More integrated with the spaces Integration More integrated with the spaces Less integrated with the spaces Control Value (CV) Greater connectivity Lesser connectivity Sustainability 2019, 11, 1582 8 of 15 Sustainability 2019, 11, x FOR PEER REVIEW 8 of 15

(a) (b) (c)

Figure 6.6. SyntaxSyntax values values of indoor,of indoor, outdoor outdoor and intermediateand intermediate spaces. spaces. According According to the spatialto the syntactic spatial operationsyntactic operation mode, the mode, (a–c) spatialthe (a), syntactic (b), (c) spatial values syntactic in FIG.5 values are calculated. in FIG. 5 are calculated.

Syntax values values should should be be interpreted interpreted according according to to the the practices practices of ofthose those people people in the in thehouse. house. As Asshown shown in Layout in Layout (a), 𝑴𝑫 (a), andMD 𝑹𝑨and haveRA havethe lowest the lowest values valuesfor all three for all spaces three C, spaces V, and C, O. V, Outdoor and O. Outdoorspace, corridor space, corridorspace, and space, indoor and space indoor are space equall arey equallyconvenient convenient in implementation, in implementation, and the and entire the entirespace is space shallow is shallow and highly and integrated. highly integrated. All spaces All ha spacesve similar have connectivity similar connectivity to each other; to each therefore, other; therefore,access to and access utilization to and utilizationof different of spaces different in Layout spaces in(a) Layout are easy (a) for are residents. easy for residents.In this case, In while this case, the whilelayout the is considered layout is considered more reasonable, more reasonable, the privacy the of privacy each space of each is lower. space is lower. In LayoutLayout (b),(b), thetheRA 𝑹𝑨value value of of outdoor outdoor space space C isC loweris lower than than that that ofV of and V and O, which O, which indicates indicates that Cthat is moreC is more highly highly integrated integrated in the in space the space than thethan other the two.other In two. addition, In addition, the “CV” the control“CV” control value ofvalue C is higher,of C is higher, indicating indicating its high its connectivity high connectivity and importance and importance in the space. in the Indoorspace. Indoor and intermediate and intermediate spaces arespaces relatively are relatively independent independent and have and better have privacy. better privacy. Layout (c) shows a different situation; in this case, the most integrated space is intermediate space V, whichwhich has a high CV and a low RA𝑹𝑨 value. value. TheThe indoorindoor spacespace mustmust bebe accessedaccessed through the intermediate spacespace fromfrom the the outdoor outdoor space, space, thus, thus, the the indoor indoor space space becomes becomes deeper. deeper. This This situation situation has anhas indoor an indoor space space that that has ahas higher a higher degree degree of privacy of privacy and and security. security. The above example explains the terminology used in syntactic analysis [[36].36]. The example also shows thethe space space types types that that can can be providedbe provided according according to the to culture the culture and life and of the life people of the in people a particular in a society.particular For society. example, For for example, the indoor for layout, the indoor different layout, cultural different and living cultural needs haveand differentliving needs functional have layoutdifferent requirements. functional layout The above requirements. three spaces The may abov bee laid three out spaces in traditional may be buildings. laid out Syntaxin traditional values (depthbuildings. and Syntax connectivity) values resonate(depth and with connectivity) different space resonate layouts, with and different this situation space canlayouts, be illustrated and this bysituation complex can space be illustrated layouts. Inby thecomplex next section, space layouts. the traditional In the next Chinese section, siheyuan the traditional is illustrated Chinese with examplessiheyuan tois discussillustrated the with cultural examples information to discuss related the to thecultural syntactic information attributes related of the house.to the syntactic attributes of the house. 5. Reading the Space Syntax of Traditional Siheyuan

5.1.5. Reading Analysis the Diagram Space ofSyntax Convex of Space Traditional of Siheyuan Siheyuan

5.1. AnalysisAccording Diagram to the of Convex Convex Map Space modeling of Siheyuan method in space syntax, the plan of a traditional siheyuan building is transformed into a space system composed of a convex map, and the space relationships According to the Convex Map modeling method in space syntax, the plan of a traditional are set (see Figure7). siheyuan building is transformed into a space system composed of a convex map, and the space relationships are set (see Figure 7). In order to illustrate the relationship among the spaces in the siheyuan, the researcher used the SketchUp software to draw the quadrature axonometric map (see Figure 8), and then use the quantitative approach of space syntax to calculate the syntactic value of each point in the siheyuan space. As the number of space points is huge, the researcher divided the spatial relationship diagram into three pictures for explanation, which present the outdoor space syntax value distribution points, the intermediate space syntax value distribution points, and the indoor space syntax value distribution points (see Figures 9–11). Sustainability 2019, 11, 1582 9 of 15 Sustainability 2019, 11, x FOR PEER REVIEW 9 of 15

Sustainability 2019, 11, x FOR PEER REVIEW 9 of 15

(a) (b) (c)

FigureFigure 7.7.Siheyuan Siheyuan Convex Convex Map Map System System Analysis Analysis Diagram; Diagram; (a) is the(a) spaceis the planspace of theplan original of thebuilding, original (building,b) is the transformed (b) is the spacetransformed syntax—convex space syntax—convex map system diagram, map (systemc) is the diagram, space relationship (c) is the diagram space transformedrelationship bydiagram Donald transformed Preziosi’s mark by analysisDonald methodPreziosi’s according mark analysis to the topological method according relationship. to the topological relationship. In order to illustrate the relationship among the spaces in the siheyuan, the researcher used the SketchUp software to(a draw) the quadrature axonometric(b) map (see Figure(c) 8), and then use the quantitative approach of space syntax to calculate the syntactic value of each point in the siheyuan space.Figure As the 7. numberSiheyuan of Convex space pointsMap Syst is huge,em Analysis the researcher Diagram; divided (a) is the the space spatial plan relationship of the original diagram into threebuilding, pictures (b) is for the explanation, transformed which space present syntax—convex the outdoor map space system syntax diagram, value ( distributionc) is the space points, the intermediaterelationship spacediagram syntax transformed value distribution by Donald points, Preziosi’s and mark the indoor analysis space method syntax according value distribution to the pointstopological (see Figures relationship.9–11).

Figure 8. Siheyuan axonometric drawing.

Figure 8. Siheyuan axonometric drawing. Figure 8. Siheyuan axonometric drawing.

Figure 9. Outdoor space syntax value distribution points.

Figure 9. Outdoor space syntax value distribution points. Sustainability 2019, 11, x FOR PEER REVIEW 9 of 15

(a) (b) (c)

Figure 7. Siheyuan Convex Map System Analysis Diagram; (a) is the space plan of the original building, (b) is the transformed space syntax—convex map system diagram, (c) is the space relationship diagram transformed by Donald Preziosi’s mark analysis method according to the topological relationship.

Sustainability 2019, 11, 1582 10 of 15 Figure 8. Siheyuan axonometric drawing.

Sustainability 2019, 11, x FOR PEER REVIEW 10 of 15 Sustainability 2019, 11, x FOR PEER REVIEW 10 of 15 FigureFigure 9.9. OutdoorOutdoor spacespace syntaxsyntax valuevalue distributiondistribution points.points.

Figure 10. Intermediate space syntax value distribution points. FigureFigure 10.10. IntermediateIntermediate spacespace syntaxsyntax valuevalue distributiondistribution points.points.

FigureFigure 11.11. IndoorIndoor spacespace syntaxsyntax valuevalue distributiondistribution points.points. Figure 11. Indoor space syntax value distribution points. 5.2.5.2. ResultsResults AnalysisAnalysis 5.2. Results Analysis TheThe residence is a a traditional traditional standard standard three-entr three-entranceance siheyuan. siheyuan. In Inthe the big big courtyard courtyard house, house, the The residence is a traditional standard three-entrance siheyuan. In the big courtyard house, the thefirst first entrance entrance is the is thehouse house door. door. According According to the to thedistribution distribution point point characteristics characteristics of Figures of Figures 9–11,9–11 its, first entrance is the house door. According to the distribution point characteristics of Figures 9–11, its itsroom room has has a relatively a relatively high high 𝑹𝑨RA valuevalue and and a a low low CV CV value, meaning poor connectivityconnectivity andand beingbeing room has a relatively high 𝑹𝑨 value and a low CV value, meaning poor connectivity and being lowlylowly integrated.integrated. AccordingAccording toto thethe traditionaltraditional cultureculture ofof siheyuansiheyuan andand people’speople’s livingliving habits,habits, itit isis notnot lowly integrated. According to the traditional culture of siheyuan and people’s living habits, it is not becausebecause thethe spacespace needsneeds privacy,privacy, butbut becausebecause thethe roomroom isis locatedlocated inin thethe southsouth andand facesfaces thethe north,north, because the space needs privacy, but because the room is located in the south and faces the north, whichwhich belongsbelongs toto aa relativelyrelatively poorpoor positionposition inin thethe wholewhole siheyuan.siheyuan. TheThe mainmain functionsfunctions ofof thethe firstfirst which belongs to a relatively poor position in the whole siheyuan. The main functions of the first entranceentrance areare welcomingwelcoming guests,guests, storingstoring goods,goods, etc.etc. However,However, asas itsits courtyardcourtyard spacespace isis thethe necessarynecessary entrance are welcoming guests, storing goods, etc. However, as its courtyard space is the necessary placeplace toto connectconnect thethe outsideoutside andand thethe innerinner courtyard, the courtyard has low RA𝑹𝑨 value value andand highhigh CVCV place to connect the outside and the inner courtyard, the courtyard has low 𝑹𝑨 value and high CV value,value, meaningmeaning itit hashas goodgood connectivityconnectivity andand isis highlyhighly integrated.integrated. value, meaning it has good connectivity and is highly integrated. The second entrance is the place where the host lives, which is located in the center of the The second entrance is the place where the host lives, which is located in the center of the siheyuan. The interesting thing is that all rooms in the binary space can only be accessed through the siheyuan. The interesting thing is that all rooms in the binary space can only be accessed through the intermediate space. We can see the syntactic value distribution characteristics of the intermediate intermediate space. We can see the syntactic value distribution characteristics of the intermediate space corridor (Figure 10). As the number of controlled rooms is different, the connecting spaces on space corridor (Figure 10). As the number of controlled rooms is different, the connecting spaces on all sides have different values; however, their common characteristics have relatively low 𝑹𝑨 values all sides have different values; however, their common characteristics have relatively low 𝑹𝑨 values and high CV values. As the main connecting space, it has strong connectivity and is highly and high CV values. As the main connecting space, it has strong connectivity and is highly integrated. The rooms also have certain patterns; spaces with poor connectivity are the side room integrated. The rooms also have certain patterns; spaces with poor connectivity are the side room spaces on the left and right sides of the host room, while the toilet and kitchen are next to the wing spaces on the left and right sides of the host room, while the toilet and kitchen are next to the wing room with high 𝑹𝑨 value and low CV value, proving that these spaces all need high concealment. room with high 𝑹𝑨 value and low CV value, proving that these spaces all need high concealment. From the 𝑴𝑫 value and CV value, we can see that the position of the host room is higher than the From the 𝑴𝑫 value and CV value, we can see that the position of the host room is higher than the wing rooms on both sides with high 𝑴𝑫 value and CV value, indicating that its privacy is higher wing rooms on both sides with high 𝑴𝑫 value and CV value, indicating that its privacy is higher than the wing rooms. At the same time, its connectivity is also higher than the wing rooms on both than the wing rooms. At the same time, its connectivity is also higher than the wing rooms on both sides; therefore, it is a verified fact that the cultural characteristic of “the north room is the most sides; therefore, it is a verified fact that the cultural characteristic of “the north room is the most superior and the two wing rooms are the second superior ones”. superior and the two wing rooms are the second superior ones”. In the third entrance, this characteristic can be seen from the 𝑴𝑫 value of the room, which has In the third entrance, this characteristic can be seen from the 𝑴𝑫 value of the room, which has the highest 𝑴𝑫 value and CV value of the whole siheyuan, indicating its deep location, poor the highest 𝑴𝑫 value and CV value of the whole siheyuan, indicating its deep location, poor Sustainability 2019, 11, 1582 11 of 15

The second entrance is the place where the host lives, which is located in the center of the siheyuan. The interesting thing is that all rooms in the binary space can only be accessed through the intermediate space. We can see the syntactic value distribution characteristics of the intermediate space corridor (Figure 10). As the number of controlled rooms is different, the connecting spaces on all sides have different values; however, their common characteristics have relatively low RA values and high CV values. As the main connecting space, it has strong connectivity and is highly integrated. The rooms also have certain patterns; spaces with poor connectivity are the side room spaces on the left and right sides of the host room, while the toilet and kitchen are next to the wing room with high RA value and low CV value, proving that these spaces all need high concealment. From the MD value and CV value, we can see that the position of the host room is higher than the wing rooms on both sides with high MD value and CV value, indicating that its privacy is higher than the wing rooms. At the same time, its connectivity is also higher than the wing rooms on both sides; therefore, it is a verified fact that the cultural characteristic of “the north room is the most superior and the two wing rooms are the second superior ones”. In the third entrance, this characteristic can be seen from the MD value of the room, which has the highest MD value and CV value of the whole siheyuan, indicating its deep location, poor connectivity, and high privacy. This space is usually a private room or boudoir, which is the activity space of women or their families, and ordinary people are not allowed to enter at will (Figures9–11).

5.3. Discussion The above comments have discussed the traditional Chinese siheyuan in detail according to space syntax. As the basic residential type in China for thousands of years, the courtyard-style residence, the siheyuan, has some valuable spatial characteristics that are difficult for other residential types to realize. However, with the increase of urban population brought about by modern urbanization, the horizontal development based on siheyuan typology can no longer adapt to the growth of modern urban population density. While modern high-rise buildings provide more residents with well-equipped housing, they have lost those traditional space, as well as social and cultural, values. The following is a survey of the traditional siheyuan and modern apartment houses with two different layouts according to connectivity, integration, and depth indices, as based on visibility graph analysis in the space syntax (Table2). Through analysis and comparison with traditional siheyuans, modern residences have the following characteristics:

(1) The entrance and corridor of modern residences have high connectivity and integration, which means that family privacy is gradually declining. (2) In modern apartment buildings, the highest connectivity in the hall occurs at the door-to-door position of apartment units on the same floor. In other words, when the door is opened, other apartments can see the interior of the house, thus, affecting the privacy of the family. (3) In the bedrooms of traditional and modern residences, the connectivity and integration index are extremely small, while the depth values are large. However, in modern residences, private space is usually protected only by doors, and if the door is opened, the interior of the space will be displayed. In traditional houses, the entire space is private, because the intermediate space (corridor) separates the courtyard and the interior space to prevent the private space from being directly exposed to other spaces. SustainabilitySustainability 2019Sustainability, 11, 2019x FOR, 112019 PEER, x ,FOR 11 REVIEW, x PEER FOR PEERREVIEW REVIEW 11 of 15 11 of 1511 of 15 connectivity,Sustainabilityconnectivity,Sustainability 2019connectivity,Sustainability and, 11, high2019x FOR and, 112019privacy. PEER, highxand ,FOR 11 REVIEW, highxprivacy. PEER FORThis privacy. PEERREVIEW space This REVIEW is Thisspace usually space is usually a privateis usually a private room a private or room boudoir, room or boudoir, whichor boudoir, iswhich the which activity is11 theof 15is activity the11 of activity 1511 of 15 space ofspace womenspace of women or of their women or families, their or theirfamilies, and families, ordinary and ordinaryand people ordinary peopleare not people areallowed not are allowed notto enter allowed to at enter will to enter (Figuresat will at (Figureswill 9–11). (Figures 9–11). 9–11). connectivity,connectivity,connectivity, and high and privacy. highand highprivacy. This privacy. space This is Thisspace usually space is usually a privateis usually a privateroom a private or room boudoir, room or boudoir, orwhich boudoir, iswhich the which activity is the is activity the activity 5.3.space Discussion of5.3.space women Discussion5.3.space of womenDiscussion or of their women or families, their or their families, and families, ordinary and ordinaryand people ordinary peopleare not people areallowed not are allowed notto enter allowed to at enter will to enter (Figuresat will at (Figureswill 9–11). (Figures 9–11). 9–11). The above comments have discussed the traditional Chinese siheyuan in detail according to 5.3. Discussion5.3. DiscussionThe5.3. DiscussionaboveThe above comments comments have have discussed discussed the traditionalthe traditional Chinese Chinese siheyuan siheyuan in detail in detail according according to to space syntax.spacespace syntax. As thesyntax. Asbasic the As residential basicthe basic residential typeresidential in type Ch ina typein forCh in inathousands Ch forina thousandsfor ofthousands years, of theyears, of courtyard-styleyears, the courtyard-stylethe courtyard-style residence,Theresidence, above theresidence,The siheyuan,commentsaboveThe the above siheyuan,thecomments has havesiheyuan,comments some discussed hashave valuable somehashave discussed somethe discussedvaluable traditionalspatial valuable the traditionalspatialthecharacteristics Chinesetraditionalspatial characteristics Chinese characteristicssiheyuan Chinesethat siheyuan are inthat siheyuandetaildifficult thatare in according detaildifficultare infor detaildifficult accordingother forto according otherfor to other to residentialspace syntax.residentialspace typesresidentialspace syntax.As tothesyntax.types realize. As basictypes to theAs realize. residential However,basictothe realize. basic residentialHowever, type withresidentialHowever, inthe typewith Ch increase ina type withinthe forCh increaseinthe ina thousandsofCh increaseurbanforina ofthousandsfor populaurban ofthousandsof years,urban tionpopula of theyears,populabrought oftion courtyard-styleyears, thetionbrought about courtyard-style thebrought courtyard-style byabout about by by modernresidence,modernresidence, urbanization, themodernresidence, urbanization,siheyuan, the urbanization, thesiheyuan,the horizontal hassiheyuan, the some horizontal hasthe development horizontalvaluablehassome some developmentvaluable spatial developmentvaluable based spatialcharacteristics on based spatial siheyuan basedcharacteristics on siheyuancharacteristics on typologythat siheyuan aretypology that can difficult typology thatnoare can longer difficultare forno candifficult adaptlongerother no for longer adaptotherfor adaptother toresidential the growthtoresidential the typestoresidential growth ofthe modern growthtotypes realize.of typesmodern urbanto of realize. modern However,to population urbanrealize. However,urban population withHowever, densitpopulation the with y. increasedensit While withthe densit y. increase the modernWhileof y. increaseurban While modern ofhigh-rise populaurban modernof high-riseurban buildingstionpopula high-rise populabrought buildingstion provide buildingstionbrought about providebrought more by aboutprovide moreabout by more by residentsmodernresidentsmodern urbanization, withresidentsmodern well-equipped urbanization, with urbanization, with well-equippedthe horizontalwell-equipped thehousing, horizontal the development housing,horizontal they housing, developmenthave they development lost based theyhave those haveon lostbased siheyuantraditional those lostbased on those siheyuantraditional on typology space,siheyuantraditional typology asspace, can welltypology nospace, as ascanlonger wellsocial as nocan wellasadaptlonger no andsocial aslonger adaptsocial and adapt and cultural,to the growthcultural,to values. thecultural,to growth ofthe values. modern growth values.of modern urban of modern population urban urban population densitpopulationy. densit While density. modern Whiley. While modern high-rise modern high-rise buildings high-rise buildings provide buildings provide more provide more more residentsTheresidents followingwithTheresidents well-equipped followingThewith is following withawell-equipped survey iswell-equipped a housing, surveyofis athe survey housing, traditionalof they the housing, of traditionalhave the they sitraditional lostheyuan theyhave those sihave lostheyuan and traditionalsi thoselostheyuan modern and those traditional modernand apartment space,traditional modern asapartmentspace, well houses apartmentspace, asas well social houseswithas wellas houses twoand social with as social withtwoand twoand differentcultural,differentcultural, values.layoutsdifferentcultural, values.layouts according values.layouts according to according connectivity, to connectivity, to connectivity, integration, integration, integration,and depth and indices,depthand depth indices, as basedindices, as onbased as visibility based on visibility on visibility graphThe analysisgraph followinggraphThe analysis in followingThe the analysis is following space ain survey the is insyntax space athe surveyofis space a thesyntax(Table survey traditionalof syntax the2).(Table of traditional the(Table 2). sitraditionalheyuan 2). siheyuan and siheyuan modern and modernand apartment modern apartment houses apartment houseswith houses two with withtwo two differentSustainabilitydifferent layoutsdifferent2019 layouts according, 11 layouts, 1582 according to according connectivity, to connectivity, to connectivity, integration, integration, integration,and depth and indices,anddepth depth indices, as basedindices, as onbased as visibility based on visibility 12on of visibility 15 graph analysisgraphgraph analysis inTable the analysis space 2.inTable Traditional the insyntaxTable space2. the Traditional space2. siheyuan(Tablesyntax Traditional syntax 2).siheyuan(Table and siheyuan(Table Modern 2). and 2). Modern housesand Modern Visibilityhouses houses Visibility graph Visibility analysis. graph graph analysis. analysis.

Table 2. Traditional siheyuan and Modern houses Visibility graph analysis. ArchitectureArchitectureArchitecture TableTraditional 2.Table TraditionalTraditional Table 2. TraditionalSiheyuan Traditional 2. siheyuan Traditional Siheyuan siheyuan Siheyuan and siheyuan Modern and Modern housesand Modern Visibilityhouses Modern houses Visibility Moderngraph Houses Visibility Modern analysis. graph Houses graph analysis.Houses analysis.

ArchitectureArchitectureArchitectureArchitecture Traditional Traditional TraditionalSiheyuan Traditional Siheyuan SiheyuanSiheyuan Modern Modern Modern Houses Modern Houses Houses Houses

Plan MapPlan PlanMap Map

Plan MapPlan PlanMapPlan Map

1. GATE1. GATE1. GATE

2. DaoZuoFang2. DaoZuoFang2. DaoZuoFang 1. Sitting1. Sittingroom1. Sitting room room 3.1. FOREGATE3.1. COURT FOREGATE1.3.1. GATEFOREGATE COURT COURT 2. Dining2. Diningroom2. Dining room room 4.2. CORRIDORDaoZuoFang4.2. CORRIDORDaoZuoFang2.4.2. DaoZuoFangCORRIDORDaoZuoFang 1. Sitting3. kitchen1.1. Sitting roomSitting3. kitchen1. Sitting room3. roomkitchen room 3. FORE COURT 2. Dining room 5.3. KITCHENFORE5.3. COURTKITCHENFORE5.3. KITCHENFORE COURT COURT 2. 4.Dining Bedroom2.4. Diningroom Bedroom2. 4.Dining Bedroom room room 4. CORRIDOR4. CORRIDOR4.4. CORRIDORCORRIDOR 3. kitchen3.3. kitchen kitchen 3. kitchen 6. BATHROMM6. BATHROMM5.6. KITCHENBATHROMM 5. Toilet&Bathroom5. Toilet&Bathroom4. Bedroom5. Toilet&Bathroom 7.5. INNERKITCHEN7.5. INNERKITCHEN COURT6.7.5. BATHROMMINNERKITCHEN COURT COURT 4.6. 5.BedroomHallway Toilet&Bathroom4.6. BedroomHallway 4.6. BedroomHallway 8.6. WESTBATHROMM8.6. WINGWESTBATHROMM7.8.6. INNERWESTBATHROMM WING WING COURT 5. Toilet&Bathroom7. balcony5. Toilet&Bathroom6.7.5. Hallway balconyToilet&Bathroom 7. balcony 9.7. EASTINNER9.7. WING EASTINNER COURT8.9.7. WESTEASTINNER WING COURT WINGWING COURT 8. House6. Hallway8. 7.gardensHouse6. balcony8. Hallway House 6. gardens Hallway gardens 8. WEST8. WINGWEST9.8. EASTWEST WING WING WING 7. 8.balcony House7. balcony gardens7. balcony 10. MAIN10. ROOMMAIN10.10. MAINMAIN ROOM ROOM ROOM 9. Public9.9. Public corridorPublic9. corridorPublic corridor corridor 9. EAST WING 8. House gardens 11.9. EAST ErFang11.9. WING EAST ErFang 11.11. ErFang ErFangWING 8. House10. The8.10. gardensHouse10. lifts The The 10. lifts gardens liftsThe lifts 12.10. BACKMAIN12.10. COURTBACKROOMMAIN12.12.10. BACKBACKMAIN COURTROOM COURT COURTROOM 9. Public11.9. stair corridorPublic11.11.9. stair Public stair corridor11. stair corridor 13.11. HouZhaoFangErFang13.11. HouZhaoFangErFang 13.13.11. HouZhaoFangHouZhaoFangErFang 10. The10. lifts The 10. liftsThe lifts 12. BACK12. COURTBACK12. BACK COURT COURT 11. stair11. stair11. stair 13. HouZhaoFang13. HouZhaoFang13. HouZhaoFang

Depth DepthDepthDepth

Depth DepthDepth

SustainabilitySustainability 2019, 112019, x ,FOR 11, x PEER FOR PEERREVIEW REVIEW 12 of 1512 of 15 Sustainability 2019Sustainability, 11, x FOR 2019 PEER, 11 REVIEW, x FOR PEER REVIEW 12 of 15 12 of 15 SustainabilitySustainability 2019, 11, 2019x FOR, 11 PEER, x FOR REVIEW PEER REVIEW 12 of 15 12 of 15

integrationintegrationintegration integrationintegration

ConnectivityConnectivityConnectivityConnectivity

ThroughThrough analysisThrough analysis and analysis comparison and andcomparison comparison with traditional with withtraditional siheyuans,traditional siheyuans, modernsiheyuans, modern residences modern residences haveresidences the have have the the ThroughContemporaryThrough analysis analysis and apartment comparison and comparison layouts with do traditional notwith produce traditional siheyuans, more siheyuans, social modern interaction modern residences than residences thehave traditional the have the followingfollowing characteristics:following characteristics: characteristics: followingsiheyuansfollowing characteristics: in characteristics: terms of family scale, meaning most of the layout is economical in area and reasonable

(1) The(1)(1) entrance (1)The entranceThe and entrance corridor and corridorand of moderncorridor of modern residences of modern residences have residences high have connectivity have high highconnectivity connectivity and integration, and integration,and integration,which which which means meansthat familymeans that privacyfamilythat family privacy is gradually privacy is gradually is declining. gradually declining. declining.

(2) In (2)(2)modern (2)InIn modernmodern apartmentIn modern apartmentapartment buildings,apartment buildings,buildings, the buildings, highest thethe highesthighest theconnect highest connectconnectivity connect inivityivity the hallivity inin thethe occurs in hallhall the occursatoccurshall the occurs door-to-door atat thethe at door-to-doordoor-to-door the door-to-door positionposition of apartmentposition of apartment of units apartment on units the units onsame the on floor. same the sameIn floor. other floor. In words, otherother In other words,words,when words, the whenwhen door when thethe is door door opened,the door isis opened,opened, other is opened, otherother other apartmentsapartments apartmentscan see can the see interiorcan the see interior ofthe the interior house, of the of house,thus, the house, affecting thus, thus, affecting the affecting privacy the privacy theof the privacy family. of the of family. the family.

(3) In (3)(3)the bedrooms(3)InIn thetheIn bedrooms bedroomsthe of bedrooms traditional ofof traditionaltraditional of andtraditional modern andand modernandmodern residences, modern residences,residences, theresidences, connectivity thethe connectivity connectivitythe connectivity and integration andand integrationandintegration integrationindex indexindex index are extremelyare extremelyare small, extremely whilesmall, small, the while depth while the valuesdepth the depth valuesare large. values are However, large.large. are large. However,However, in However, modern inin modernmodern residences,in modern residences,residences, privateresidences, private private private space isspace usuallyspace is usually protected is usually protected only protected by only doors, onlyby anddoors, by ifdoors, th ande door ifand th ise if door opened,the door is opened, the is opened,interior the interior ofthe the interior space of the of will space the space will will be displayed.be displayed.be Indisplayed. traditional In traditional In houses,traditional houses, the houses,entire the spaceentire the entire is space private, space is private, because is private, because the becauseintermediate the intermediate the intermediate space space space (corridor)(corridor)(corridor) separates(corridor) separatesseparates the separates courtyard thethe courtyardcourtyard the and courtyard the andand interior thetheand interiorinterior spacethe interior to spacespace prevent space toto preventprevent the to preventprivate thethe private private spacethe private from spacespace beingspace fromfrom from beingbeing being directlydirectly exposeddirectly exposed to otherexposed to spaces. other to other spaces. spaces. ContemporaryContemporaryContemporary apartment apartment layoutsapartment layouts do notlayouts doproduce not do producenot more produce social more more interactionsocial social interaction thaninteraction the than traditional thanthe traditionalthe traditional siheyuanssiheyuans insiheyuans terms in of terms familyin terms of familyscale, of family meaning scale, scale, meaning most meaning of most the mostlayout of thethe of islayoutlayout the economical layout isis economicaleconomical is economicalin area ininand areaarea inreasonable areaandand reasonablereasonableand reasonable in function.inin function.function. inAlthough function. AlthoughAlthough the Although space thethe functions space spacethe space functionsfunctions are functions perfec arearet, perfec perfec arethey perfec t,t,do theythey nott, they dodohave notnot do the havehavenot function have thethe function functionthe of functiontraditional ofof traditionaltraditional of traditional courtyards.courtyards. courtyards.Without Without a central Without a centralspace, a central suchspace, space,as such a cour suchastyard, a couras a peopletyard,tyard,courtyard, peoplepeoplenot onlypeople notnot lose only onlynot the onlyloselose outdoor thelosethe outdooroutdoor the space outdoor to spacespace space toto to contactcontact withcontact nature, with withnature, they nature, also they lose theyalso the losealso space thelose for space the family space for familycommunication. for family communication. communication.

6. Conclusions6. Conclusions6. Conclusions This studyThis Thiselaboratesstudy study elaborates theelaborates concepts the conceptsthe and concepts applications and andapplications applications of syntactic of syntactic of analysis, syntactic analysis, as analysis, well as as well asthe well as the as the relationshiprelationshiprelationship between between the between syntactic the syntactic the attributes syntactic attributes of attributes spec ofific spec buildings of ificificspec buildingsbuildingsific in buildings a specific inin aa specificinspecific area a specific and areaarea the areaandand culture theandthe culture culturethe culture and lifeand of thelifeand peopleof life the of people inthe that people inarea. that in Metaphorically, area.that area. Metaphorically, Metaphorically, the concept the concept theof spaceconcept of in space theof space spacein the in syntax space the space syntaxtheory syntax theory theory can be cancompared becan compared be withcompared linguistic with withlinguistic concepts. linguistic concepts. Although concepts. Although language Although languagelanguage is languagefull ofisis fullfullvitality, is ofoffull vitality,vitality, itof willvitality, itaffectit willwill it thewillaffectaffect affect thethe the cultureculture of theculture speaker,of the of speaker,the and speaker, culture and andculture will culture influenc will willinfluence the influenc formatione thee formationthe offormation language of language of over language time. over Without overtime. time. Without Without understandingunderstandingunderstanding the culture the culturethebehind culture behindlanguage, behind language, one language, ca nnotone caonefullynnot ca understand nnotfully fullyunderstand understandthe language. the language.th eSimilarly, language. Similarly, Similarly, the studythethe of studystudythe space study ofof is spacespace incomplete, of space isis incomplete,incomplete, is incomplete,meaning meaningmeaning it has meaning no itit t hashas been it nono has linkedtt beenbeen not been withlinkedlinked linkedpeople’s withwith with people’speople’s culture people’s culture cultureand culturelife. andand Space life.life.and SpaceSpacelife. Space organizationorganizationorganization is a function is a function is of a thefunction form of the of form thesocial form of so sociallidarity, of social solidarity,lidarity, and solidarity, different andand differentdifferentand forms different of formsforms social forms ofof solidarity socialsocial of social solidaritysolidarity are solidarity areare are based onbased societybased on societyas on a societyspace as a and spaceas a cross-space space and cross-spaceand cross-spacesystem .system Through system.. ThroughThrough this. Through study, thisthis thestudy,study,this following study, thethe following followingthe conclusions following conclusionsconclusions conclusions are summarized:are summarized:are summarized:

1. The1. paper1.The calculatespaperThe paper calculates the calculates syntax the syntax valuethe syntax ofvalue each value of space each of ineachspace the space siheyuanin the in siheyuan the through siheyuan through the through quantitative the quantitative the quantitative methodmethod of methodspace of spacesyntax.of space syntax. Then syntax. itThen analysesThen it analyses it theanalyses relationship thethe therelationshiprelationship relationship between betweenbetween thebetween distribution thethe thedistributiondistribution distribution characteristicscharacteristicscharacteristics of the syntax of the of syntaxvalue the syntax and value the value and influence theand influence the of influence traditional of traditional of culturetraditional culture on the culture spatialon the on spatiallayout. the spatial layout. layout. Sustainability 2019, 11, 1582 13 of 15 in function. Although the space functions are perfect, they do not have the function of traditional courtyards. Without a central space, such as a courtyard, people not only lose the outdoor space to contact with nature, they also lose the space for family communication.

6. Conclusions This study elaborates the concepts and applications of syntactic analysis, as well as the relationship between the syntactic attributes of specific buildings in a specific area and the culture and life of the people in that area. Metaphorically, the concept of space in the space syntax theory can be compared with linguistic concepts. Although language is full of vitality, it will affect the culture of the speaker, and culture will influence the formation of language over time. Without understanding the culture behind language, one cannot fully understand the language. Similarly, the study of space is incomplete, meaning it has not been linked with people’s culture and life. Space organization is a function of the form of social solidarity, and different forms of social solidarity are based on society as a space and cross-space system. Through this study, the following conclusions are summarized:

1. The paper calculates the syntax value of each space in the siheyuan through the quantitative method of space syntax. Then it analyses the relationship between the distribution characteristics of the syntax value and the influence of traditional culture on the spatial layout. The analysis indicates that the spatial layout is related to culture, and that the spatial order of any particular area is part of the culture of this area. The spatial relationship between outdoor and indoor space and the intermediary space of the traditional siheyuan is influenced by traditional Chinese culture. Previous studies scarcely seem to connect the spatial form of the siheyuan with social functions of courtyards, cultural concepts and human activities. We should try to inherit the cultural significance of a traditional siheyuan and realize its sustainable development. 2. The results of the analytical comparison between the traditional residence and modern residence shows that privacy in a modern residence is not respected. Although this change may be due to modern lifestyle and new technology, it is necessary to consider briefly the physical and spiritual needs of human beings. Recent centuries show that many such needs have existed in human history. It is necessary to improve the privacy of the modern residence. A comprehensive inspection of this type of building to extract and redefine the concepts lacking in contemporary life will undoubtedly help meet the basic needs of society. 3. The change in the Chinese family structure demands a subsequent change in the housing form, which has implications for new housing designs [38,39]. For example, in siheyuans in Beijing, adult children need additional rooms in the courtyard, which makes the courtyard full of impromptu expansion, and this situation has led to the decline and mass demolition of traditional siheyuans. In order to develop traditional Chinese architectural culture, we must design new houses that consider whether they are culturally sustainable, and whether they are conducive to the traditional cultural expression of residents, according to the aspects of environment, space, society, culture, and behavior, in order to better apply traditional cultural values to modern design and promote the sustainability of cultural heritage. 4. In addition to studying the sustainability of the traditional siheyuan culture from the perspective of space syntax value, the influence of social and cultural aspects, such as historical context, language, folk beliefs, religion, values, norms, customs, ideology, symbols and even the way of daily life on the spatial organization of the traditional siheyuan, can also be explored in future studies. The traditional Chinese siheyuan can be regarded as a successful and sustainable design strategy, thanks to its double functions of privacy and security. In the process of design, space layout and social and cultural backgrounds are carefully considered. They have responded to the most serious environmental challenges and social and cultural needs for a long time. Due to population growth and the changes of cultural values and society, these traditional principles may not apply to contemporary residential design, but some of them still work in residential Sustainability 2019, 11, 1582 14 of 15

design in urban areas with similar environmental and cultural characteristics, thus promoting the sustainable development of traditional culture.

Author Contributions: B.-X.H. contributed to the conceptual design of the study, data collection, drafting the article, and final approval. W.-Y.L contributed to the conceptual design of the study, data collection. S.-C.C. contributed to the conceptual design of the study, supervision of the progress, and final approval. Funding: This research received no external funding. Conflicts of Interest: The authors declare no conflict of interest.

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