Infill architecture: Design approaches for in-between buildings and 'bond' as integrative element

The aim of the paper is to draw attention to the view that the two key elements in achieving good quality of architecture infill in immediate, current surroundings, are the selection of optimal creative method of infill architecture and adequate application of “the bond” as integrative element. The success of achievement and the quality of architectural infill mainly depend on the assessment of various circumstances, but also on the professionalism, creativity, sensibility, and finally innovativeness of the architect. In order for the infill procedure to be carried out adequately, it is necessary to carry out the assessment of quality of the current surroundings that the object will be integrated into, and then to choose the creative approach that will allow the object to establish an optimal dialogue with its surroundings. On a wider scale, both theory and the practice differentiate thee main creative approaches to infill objects: a)mimetic approach (mimesis), b)associative approach and c)contrasting approach. Which of the stated approaches will be chosen depends primarily on the fact whether the existing physical structure into which the object is being infilled is “distinct”, “specific” or “indistinct”, but it also depends on the inclination of the designer. “The bond” is a term which in architecture denotes an element or zone of one object, but in some instances it can refer to the whole object which has been articulated in a specific way, with an aim of reaching the solution for the visual conflict as is often the case in situations when there is a clash between the existing objects and the newly designed or reconstructed object. This paper provides in-depth analysis of different types of bonds, such as “direction as bond”, “cornice as bond”, “structure as bond”, “texture as bond” and “material as bond”, which indicate complexity and multiple layers of the designing process of object interpolation.

Кључне речи: архитектура, интерполација, спона, контекст, мимезис, асоцијација, контраст ABSTRACT The aim of the paper is to draw attention to the view that the two key elements in achieving good quality of architecture infill in immediate, current surroundings, are the selection of optimal creative method of infill architecture and adequate application of "the bond" as integrative element.The success of achievement and the quality of architectural infill mainly depend on the assessment of various circumstances, but also on the professionalism, creativity, sensibility, and finally innovativeness of the architect.In order for the infill procedure to be carried out adequately, it is necessary to carry out the assessment of quality of the current surroundings that the object will be integrated into, and then to choose the creative approach that will allow the object to establish an optimal dialogue with its surroundings.On a wider scale, both theory and the practice differentiate thee main creative approaches to infill objects: a)mimetic approach (mimesis), b)associative approach and c)contrasting approach.Which of the stated approaches will be chosen depends primarily on the fact whether the existing physical structure into which the object is being infilled is "distinct", "specific" or "indistinct", but it also depends on the inclination of the designer."The bond" is a term which in architecture denotes an element or zone of one object, but in some instances it can refer to the whole object which has been articulated in a specific way, with an aim of reaching the solution for the visual conflict as is often the case in situations when there is a clash between the existing objects and the newly designed or reconstructed object.This paper provides indepth analysis of different types of bonds, such as "direction as bond", "cornice as bond", "structure as bond", "texture as bond" and "material as bond", which indicate complexity and multiple layers of the designing process of object interpolation.Key words: architecture, urban infill, bond, context, mimesis, association, contrast.
The first group of authors, such as B. Brolin, I. Šverko and V. Stanković Simčić, primarily examined designing standpoints when integrating new objects into existing surroundings.They express statements which, in their opinion, explain optimal creative approaches to architectural planning in different situations, when the new infill structure is set against the old one, the new structure is set against the new one or the old structure is positioned next to the old one.The positions vary, starting from inclinations expressed by V. Stanković Simčić, towards contrasting interventions in the existing surroundings, and this author does not see the contrast as literal interpretation of that concept (sharply expressed clash, disparity), but a juxtaposition of different styles (contemporary style and the previous style) (Stanković Simčić, 1989, 2010:31), continuing to the viewpoint expressed by I. Šverko, claiming that the freedom of interpolation should not be constrained, until it compromises the elements such as unity and identity of the existing surroundings (Šverko, 1997:299), to aspirations expressed by B. Brolin who supports contextuality of the objects.This author focuses on the importance of infill, and in particular situations even mimetic submission of the new infill structure in favor of the existing one (Brolin, 1988:29).
The second group of authors, like N. Kurtović Folić and Ž. Popović, focus on various aspects of building extensions on the existing objects, where N. Kurotović Folić particularly stresses the aesthetic criteria, overall set of rules and approaches to building extensions, as well as assessment of achieved results (Kurtović Folić, 2001:13-15), while Ž.Popović finds of utmost importance the historiographic review of the most significant examples of successful building extensions in Belgrade (Popović, 2001).
object into the existing surroundings, which repeatedly shows the need to review previous standpoints, express new and different interpretations, which would all contribute to clarification of the creative design principles and methodology, but also initiate new discussions in this field.This is why the direction of further research will focus on analyses and clarification of optimal creative approaches to interpolation of architectural objects, with the aim of explaining the thesis which claims that the key elements in achieving a successful interpolation are the selection of optimal approach to interpolation and the adequate usage of "bond" as the integrative element.

THE CONCEPT AND TYPES OF INTERPOLATION
The theory defines "interpolation" in the general sense as the method of estimating a certain value which exists between the two previously known values (Terzidis, 2003:77;Vujaklija, 1980:357).According to K. Terzidis, there are numerous variations of "hybrid shapes" that stem from structural characteristics of the surrounding, existing shapes, which leads Tezidis to conclude that all of them are interpolated objects or possible interpretations of the existing ones, or as he states "the bridge that connects two different sides" (Terzidis, 2003:78).While looking for possible interpolated variations in congenerous shapes is a relatively simple process (Figure 1), interpolation of shapes in dissimilar objects can turn into a quite complex process which is particularly evident in architecturе.
The term "interpolation" in architecture denotes a creative construction method of integration of a new object or structure into older, mostly urban setting (***, 2003:1319).In a more strict meaning, the term refers to introduction of new objects or sets of objects between two neighboring, linearly positioned Сл. 1. Поступак интерполације истородних геометријских слика Fig. 1.The process of interpolation of congenerous geometric shapes Сл. 2. Oсновни типови интерполација: 1) и 5) линијски типови, 2) и 6) угаони типови, 3) и 7) уграђени типови са три стране и 4) и 8) уграђени типови са више страна Fig. 2. Basic types of interpolation: 1) and 5) linear types, 2) and 6) corner types, 3) and 7) in-between types within three sides and 4) and 8) in-between types within multiple sides objects (Figure 2.1.).In a wider sense, the term includes other options of design and construction of new objects in an older setting, as is the case in corner objects (Figure 2.2.) and infill objects within three (Figure 2.3) or more sides (Figure 2.4).In the widest sense, all architectural objects can be considered as infill objects as they include construction of something new in the existing context (Schermann, 2005:70;Marić, Niković, Manić, 2010:47).In theory and practice, other terms are also used and they define the concept of interpolation in a similar way, as "In-between building", "Urban infill", etc.
Linear type of interpolation (Figure 2.1) is the one most used in practice and it includes visual, compositional and regulational integration of the new object between the two, mostly old, existing objects.Although the usage of the term "interpolation" is mainly related to the construction of completely new objects, in practice there are also some cases when old objects are reconstructed or extended and this proves the presence, at least up to a point, of interpolation of "older", reconstructed object and its changed volumetric, artistic and stylistic adaptation to the new setting.
Corner interpolation (Figure 2.2) is found less frequently in practice and it stands for visual, compositional and regulational integration of the new object into existing objects, located in various urban settings, which means that they have different architectural characteristics.This leads to a specific problem in the construction procedure of interpolation -the issue of articulating the building with "two faces".where each "face", in its particular way, has to establish an adequate relation with the character of the setting that the new object is connected to."The faces" can differ in articulation in the same way that different settings differ, which definitely does not represent an imperative, but more of a creative potential.The issue of different "faces" can also be ignored as we look upon the object as an integral structure, which is often the case, as the object does incorporate the aspects of space, shape and function.
The three-sided interpolated object (Figure 2.3) is even less frequent in practice and its characteristic is, as with the linear type, visual and compositional link to the neighboring objects.However, as the physical structure is based on three sides, this mainly requires the introduction of skylights or atriums, which partially provide illumination for inner areas.The problem which arises in this type of interpolation is more or less direct visual contact from the areas adjoining the skylight and neighboring objects that the new object is placed next to.

CREATIVE APPROACHES TO INTERPOLATION OF ARCHITECTURAL OBJECTS
Successful creation and the quality of architectural interpolation depends on different circumstances but also on the professionalism, knowledge, creativity, sensitivity and even innovativeness of the architect himself.In order for interpolation procedure to be carried out adequately, it is necessary, at the very beginning of the designing process, to conduct evaluation of the quality of the surrounding area where the object is to be built in and then to select the creative approach which will enable the object to establish an optimal dialogue with the surrounding area (Stanković Simčić, 2010:32).
Although the procedure of interpolation may seem quite simple at first, the aim to achieve a distinct author's approach is complex, as it includes detailed analyses of the existing spatial relations, adapting the new architectural elements to various purposes, types and physical structures, as well as adequate artistic solution to street and interior facades, all of which will lead to achieving an original creative expression, with full compliance with the regulations and norms, as well as current stylistic tendencies (Kadijević, 2009:210).When establishing relations in the interpolation procedure, it is necessary to take into consideration the constitutive elements of the existing buildings (volume, height, spatial organization, horizontal and vertical facade zone division, artistic details, symbolic emphasis, construction, elements of materialization), but at the same time it is vital to aspire to establish the dialogue and the relations between the key elements of the infill object and one of the two adjoining objects (Kadijević, 2009:206;Kadijević, 2015:257).Z. Jurić and A. Vukadin stress that the key problem of interpolation of contemporary international modern architecture into historic urban centers is the stylistic class between the new and the old which creates "hybridization" of the historic ambience.If interpolation cannot be avoided, these two authors agree that the only possible option is "softening the morphological spans" (Jurić, Vukadin, 2009:133-134).
As for the selection of approaches to the design of interpolated objects, it is customary to establish the standing point on the initial assessment of the existing physical structures, depending on the particular situations and their esthetic, historic or other values, in cases of reconstruction, some of the technical methods can be used, such as: rehabilitation, adaptation, reconstruction, facsimile or methods of adaptation, emphases or detachment (Šerman, 2005:72;Vaništa Lazarević, 1999:44).In a wider context, in theory and practice, there are three distinct basic creative approaches to interpolation of objects into their surroundings (***, 2007:65; Brolin, 1988: 1. mimicry approach (mimesis) -the method of construction which reflects or imitates visual and other characteristics of the neighboring objects in that setting; 2. associative approach -the method of construction in accordance with the "spirit of a place" (genius loci) by transferring and stylizing the characteristics from the surrounding and constructing a new object in such a way that it resembles to a higher or smaller degree, the neighboring objects; 3. contrasting approach -the procedure of partial or complete denial of the characteristics of the surroundings, where a new object, visually, diverges from its setting, but at the same time blends into it.Depending on the fact whether the existing physical structure is "distinct", "specific" or "indistinct", 1 mimesis, associative and contrasting approach is are most frequently used in the following situations (Table 1.):

Mimicry approach -mimesis
Mimicry approach is present in science and practice in its different variations and under various names, such as "mimicry method", "the facsimile method", "the imitation method", "the adaptation method", etc.Most frequently, it is used in situations when the author aims to maintain the authenticity of a valuable historical ambience (spatial complex or cultural heritage) while adding an infill object.It is also used in homogenous, particularly valuable, well-maintained settings, complexes or individual objects, whose integrity has been slightly distorted and cannot be restored by means of conservation and restoration.According to V. Stanković Simčić, 1 The term "distinct" architecture denotes architectural objects and complexes which boast high esthetic values, which are extraordinary and non-standard in their visual and other characteristics, and this is the reason they are included in the category of cultural heritage of great importance.The term "specific" architecture refers to architectural objects or complexes whose characteristics make them specific in relation to most neighboring objects in their immediate or wider surroundings.They can be older or newer, but have not yet been included in the process of legal protection, which would confirm their wider significance and architectural importance."Indistinct" architecture refers to architectural examples, whether new or old, which apart from their basic functional value do not have other esthetic or semantic qualities, which is why they received no legal protection (Alfirević, 2011b:80-82).
if the aspiration of the architect is to protect the originality of the historic surroundings, then intervening through aggressive and modern architectural expression is of no use, and the same is true in cases of pseudo-historic mannerism or false storico approaches (Stanković Simčić, 2010:32-34).By advocating expert standpoint of the architect-conservator, S. Bulimbašić is of the opinion that the city is a living organism and that it should not be "frozen" in any randomly selected moment, because, as he states "it is not useful to lessen the existing values, but it is beneficial to add value, particularly if the new values are really on a par with the pre-existing quality (Bulimbašić, 2008:29).
Figure 3 shows schematic illustration of different mimicry modes, which can be established by mirroring the shape, color, structure, texture and direction.The more aspects of mimicry used in the procedure of interpolation, the more the newly designed object will blend into its immediate setting.

Associative approach
When associative approach is mentioned in science and practice, it appears under other names as well, i.e. "the transposition method", "the method of emphasis", "the method of stylization", construction or design in accordance with the "spirit of a place", etc.According to theoretician B. Brolin, imitation (or mimesis) of the existing, older physical context aims to neglect newer layers of culture, new needs, constructions and contemporary esthetic sensitivities, it even ignores any form of developed or transformed identity.On the other hand, he is of the opinion that complete rejection of the existing physical structure leads to contemporary, often even "ostentatious modernistic or technical formulas" (Brolin, 1988:VI).This indicates a moderate standpoint, based not on a firm method of approach selection, but more on a subjective feeling of the author.This stand is directed towards the process of creating interpolation, which to a greater or lesser degree relates to immediate physical surroundings and is well-suited for the present time.Its use implies transposition of properties found in the surroundings which should be stylized or discreetly indicated, as these elements identify the character and the values of the existing space.Their transposition cannot rely on direct imitation, as in that case they will downgrade the authentic values of the setting (Stanković Simčić, 2010:32).This is why A. Idrizbegović Zgonić stresses that the design of a new building in the historical context should be contemporary, that the building itself should "adapt and learn from the neighboring historical buildings", not imitate them.Historical "reminiscence" must be subtle and sophisticated, in touch with the place and the topography (Idrizbegović Zgonić, 2009:79).
Figure 4 shows schematic illustration of different types of association that can be established as association of shape, color, structure, texture and direction.The more aspects of association, the more the newly constructed object will reflect its immediate surroundings.

Contrasting approach
A more radical stand in interpolation of objects is expressed by architect B. Mitrović, who finds that the principle of contrast as the extreme form of dialogue with pre-existing geometry in the area where the architect is intervening leads to a successful architectural result, more than the method of mimicry or simple imitation of previous objects or settings, even if they are significant from the historical or architectural point of view (***, 2007:65).Mitrović explains his view by saying that if individual differences display some authentic value, in time they will overcome initial surprise or resistance towards the new objects, establishing a complex relation, as a form of confirmation of the continuity of differences.At first a new form that we are perceptually not accustomed to will provoke mistrust and skepticism.Marked individuality which contains certain honesty, undeniable value, transposed good spirit, ethical form, in time turns into a value within the chosen setting (***, 2007:65).Another architect, I. Šverko is of a similar opinion.She feels that the continual process of structuring urban space and architecture does not necessarily mean that interpolation of the object must exclude the freedom of expression outside contextual relation of the existing structure, until it compromises unity and identity of the ambience (Šverko, 1997:299).The mimicry method in the context of expressive architecture is put in the background by architect V. Stanković Simčić, as she claims that the use of old architectural-urbanistic solutions, forms and proportions frequently cannot meet modern needs, which is why she states that mimicry approach should be eliminated from the process of revitalization of cultural and historic heritage, and the solutions should be looked for through old-new integration, not old-quasi old (Stanković Simčić, 2010:31-32).According to her, the contrasting method does not stand for literal interpretation of that term (i.e.sharply expressed opposite, a contrast), but relates to juxtaposition of styles (modern with the previous style).Thus, Сл. 3. Основни визуелни аспекти миметичности: 1) миметичност облика, 2) миметичност боје, 3) миметичност структуре, 4) миметичност фактуре и 5) миметичност правца Fig. 3. Basic visual aspects of mimicry approach: 1) mimicry of shape, 2) mimicry of color, 3) mimicry of structure, 4) mimicry of texture and 5) mimicry of direction Сл. 4. Основни визуелни аспекти асоцијативности: 1) асоцијативност облика, 2) асоцијативност боје, 3) асоцијативност структуре, 4) асоцијативност фактуре и 5) асоцијативност правца Fig. 4. Basic visual aspects of association: 1) shape association, 2) color association, 3) structure association, 4) texture association and 5) direction association Сл. 5. Основни визуелни аспекти контраста: 1) контрастирање облика, 2) контрастирање боје, 3) контрастирање структуре, 4) контрастирање фактуре и 5) контрастирање правца Fig. 5. Basic visual aspects of contrast: 1) contrasting the shape, 2) contrasting the color, 3) contrasting the structure, 4) contrasting the texture and 5) contrasting  (Stanković Simčić, 2010:31).Слично становиште заступа и К. Шерман, наводећи да би улазеће "ново" требало на питање затеченог "старог" одговорити -легитимно и суверено, јасно и самоуверено -својим властитим језиком, језиком властитога доба (Šerman, 2005:72).Међутим, примена методе контраста у контексту изражајне архитектуре врло често доводи до неуспелих решења, уколико стваралац не поседује велико искуство и истанчан уметнички сензибилитет, због чега је распрострањено и становиште да би нови објекат или интерполирана целина требало, у извесној мери или у целости, да се стопе са амбијентом, како не би деградирали карактер и вредности постојеће архитектуре (Uskoković, 2011:142).По А. Идризбеговић Згонић, "принцип контраста" је, у суштини, принцип игнорисања постојећег урбаног ткива и околине.Контраст врло често ствара узбудљив исход и релацију, али када се изнова понавља, без дубље the contrasting method does not denote only juxtaposition, but also integration and harmony of the old and the new.If the contrast to the existing structure is to be emphasized, it has to be evident in relation to division of mass, its articulation, spatial organization, usage, materials, color, interior and exterior details, height relations, in other words, in all architectural and urbanistic aspects (Stanković Simčić, 2010:31).A similar view is shared by K. Shermann, who states that the incoming "new" should answer the question posed by "the old" by providing a legitimate, independent, clear and self-assured answer, in its own language, the language of the current times (Schermann, 2005:72).However, the contrasting method in the context of expressive architecture very often produces unsuccessful solution, if the creator does not have extensive experience or refined artistic sensitivity, which is why there is a wide spread standpoint that the new object or infill structure should, up to a certain point or totally, blend in with the ambience, in order not to degrade the character or values of the existing architecture (Uskoković, 2011:142).According to A. Idrizbegović Zgonić, "the contrasting principle" is in fact the principle of ignoring the existing urban tissue and its surroundings.The contrast itself can often create exciting outcomes and relations, but when it is constantly repeated without deeper essence, then the author's attitude turns into an excuse for an architect who ignores the complex aspects of the context (Idrizbegović Zgonić, 2009:7).
Figure 5 shows schematic illustration of different forms of contrasting that can be established as shape, color, structure, texture and direction contrast.The more contrasting aspects in the interpolation, the more the newly constructed object will differ from its immediate setting.

"BOND" AS AN INTEGRATIVE ELEMENT IN OBJECT INTERPOLATION
"The bond" is a term which in architecture stands for an element or a zone of one construction, and in certain situation it can refer to the whole object, which has been articulated in a specific way, with an aim of achieving the solution of the visual conflict, which occurs in situations when there is a clash between the existing objects and the newly designed or restored object.The principle of introducing the bond has been applied in architecture in numerous historical periods, however, it is particularly characteristic for modernism movement, as it is the result of the aspiration towards simpler and contrasting solutions.Furthermore, this created the idea of visual "separation" of objects and the introduction of the bond as the separating element (break-link) which serves the purpose to visually decompose, but at the same time connect diverse architectural concepts that are present in current urban environment (Brolin, 1988:83;Demiri, 2013:45).The bond can be envisaged and accomplished in various ways.B. Brolin states several different types of bonds between objects.Some are indented parts of an objects, remote from the facade and can be about ten centimeters wide, which in his view depends on the size of an object.Next, they can be made of various materials, суштине, онда такав ауторски став постаје изговор да се архитекта не позабави сложеним аспектима контекста (Idrizbegović Zgonić, 2009:7).
The way that bond emerges on an object depends on multiple factors, first of all, on the characteristics of neighboring objects, but also on the creativity of the architect (Brolin, 1988:84).If the idea of using the bond as the element is analyzed theoretically, new terms could be deduced, such as: a)"direction as bond", b)"cornices as bonds", c)"structure as bond", d)"texture as bond" and e)"material as bond".They should serve the purpose of clarifying the multiple meanings of the core term "bond" in architecture.

"Direction as bond"
One of the most applied principles, used in order to establish visual continuity of the newly constructed object with the existing ones, is lengthening the direction of facade surfaces from the neighboring objects to the new object, which enables partial transfer of the characteristics of the existing structures to the new, infill object.Figure 6 shows characteristic solutions for infill objects by means of lengthening the facade directions.
The first example (Figure 6.1.)refers to simple lengthening of the direction in instances when the facade surfaces of the neighboring objects are aligned and make a linear, continual row.The variation of this theme is present in the next example (Figure 6.2.), in cases when neighboring objects have dinamic facades, which is why the facade surface of the infill object does not fall in the same direction with any of the adjoining objects, so the new object has to be fitted in by using other interpolation elements, such as material, structure, color, etc.The third case (Figure 6.3) is present in situations when the infill object will only partially follow the direction of the facade surface of the neighboring objects, when the center of the new object exhibits a change in artistic or composition theme.A similar principle is true for the fourth case (Figure 6. начин се тема споне може појавити на објекту, зависи од више фактора, првенствено од карактеристика објеката у непосредном окружењу, али и од креативности архитекте (Brolin, 1988:84).Уколико се идеја о примени споне као елемента теоријски разложи, могу се извести нови термини попут: а) "спона-правац", б)"спона-венац", в)"спонаструктура", г)"спона-фактура" и д)"спона-материјал", који би требало јасније да одреде вишезначност основног термина "спона" у архитектури.
More complex examples of interpolation are present when the heights of neighboring objects are different in comparison with infill object (Figure 7.2.,7.3.,7.4.,7.5.,7.6.).In most of the presented cases, some type of bond is unavoidable, as shearing of different heights of roof cornices exposes gable walls, which represents a significant visual problem.In situations when the neighboring objects are oriented towards the street by their gable wall side (Figure 7.9.,7.10.,7.11.,7.12.), interpolation of the new object in the existing setting presents itself as an even more complex problem, as it is important to take into account the rhythm, roof pitch and the character of roof plane, and to adjust the bonds in accordance with these characteristics, if it is not possible to adjust the structures of facade planes.

"Structure as bond"
The inclination to adjust the structures of the newly designed object with the existing ones is aimed at transferring certain characteristics of the neighboring objects to the new, infill object (Kurtović Folić, 2001:13).Adjustments on the level of facade elements structure or architectural level can be conducted only by lengthening horizontal direction (Figure 8.1.), in situations when floor heights of the neighboring objects are of similar values as those of the new object and when the position of their facade elements, such as bay windows, loggias, windows, doors, terraces, balconies, etc. can be visually aligned with the heights on the infill object.By the same principle, the adjustment of the facade structures can be conducted through transfer of characteristic rhythm of the elements from neighboring objects to the new infill object (Figure 8.2.).Unlike the previous case, the latter principle does not require that the floor heights of objects match to a higher degree.In situations when it is not possible to adjust the facade structures of neighboring objects due to their divergent character or if their floor heights show significant shear and the difference between level, one or two bonds can be applied (Figure 8.3.,8.4.), in order to visually divide the infill object, so that it can appear as an independent and harmonious composition.In less frequent situations, when due to functional reasons there is a delevelling within the infill object, the bond can appear in the middle of the facade (Figure 8.5.), which can partially transfer the characters of the neighboring facades to the new object.A similar principle of partial transfer of facade elements can be applied in cases when the objects (neighboring and infill) are approximately of the same height when the use of bond can be avoided (Figure 8.6.).If the structural elements of the neighboring objects are too divergent, but facade elements are of the same or similar dimensions and shapes, then similar elements can be applied even on the infill object with a different formation, which creates a character similar to the one of the existing structures (Figure 8.7.).A very rare situation is the one when the width 41-2015 АУ неопходно водити рачуна и о ритму, нагибима и карактеру кровних равни, те се, у складу са тим, могу применити и споне, уколико није могуће усагласити структуре фасадних равни.

"Texture as bond"
The utilization of texture, in terms of tactility (facade plastics and surface roughness) as a principle for connecting adjoining objects with infill object, in most cases can serve only as an auxiliary tool in integrating objects into a harmonious complex (Panić, Dinulović, 2009:1732).If this principle is to become more frequently utilized in interpolation, the infill object should be surrounded by older period objects with abundant decoration and facade plastics, which can motivate possible utilization of different levels of surface tactility even on the infill object.In situations when there are clearly defined, strict conditions of ambience preservation, considering "style texture" on the infill object becomes a more significant issue.

"Material as bond"
The last level of integrating objects involves utilization of different materials, with an aim of transferring visual, artistic characteristics (color, reflection, translucence, etc.) from neighboring objects to the new, infill object.Unlike the case when texture was utilized as the bond, the use of material as a bond is one of the primary means in achieving the unity of the infill object and the surrounding objects (Panić, Dinulović, 2009:1732).Most often the same or similar material is used as the one on neighboring constructions and this establishes general artistic unity of the facades.However, if the new object has to be representative or emphasized or an example of author's expression, a significantly different material is used that the one domineering the surrounding facades, most frequently used bonds are those that use effective materials or neutral tone surfaces, thus visually separating the infill object from the existing objects and dematerializing the boundaries of their physical contact (Čarapić, 2008:25).

CONCLUSION
The paper systemizes the basic creative approaches and presents some of the basic types of bonds that can make the new infill object integrated into the compositional or artistic relation with the neighboring objects in its immediate surrounding.The paper does not favor certain construction standpoints (mimetic, association or contrasting approach) as more suitable or more adept in certain cases, but focuses more on the aspect of research of the methodological steps and options that can lead to the dialogue between the new and old in the urban setting.By providing parallel presentation of the characteristic attitudes expressed by relevant professionals who dealt with 41-2015 АУ у питању, истиче неопходност увођења савременог архитектонског слоја у постојећи контекст, што углавном води у правцу контрастних интервенција (Митровић, Шверко, Станковић Симчић, Булимбашић и др.).Друго, којим се истиче обазривост и извесна доза поштовања према затеченом окружењу, уз услов да се превише не одлута у подражавање постојеће архитектуре (Бролин, Идризбеговић Згонић, Куртовић Фолић и др.).Најмање заступљен, и чини се најмање омиљен став код аутора, јесте став да у извесним ситуацијама присуства естетски и историјски вредне архитектуре, миметичан приступ може имати посебан значај у одлучивању какав приступ заузети приликом интерполирања новог објекта у постојеће окружење.Стога се може констатовати да је сваки од стваралачких приступа у поступку одлучивања једнако вредан и да заслужује подједнако разматрање приликом пројектовањa, али је неопходно напоменути да од избора одређеног стваралачког метода не мора стриктно да зависи и финални квалитет дела, већ је од великог значаја умеће примене одабраног приступа.У раду је, такође, скренута пажња на истакнут значај "споне", као елемента који може у визуелном смислу да повеже, али у појединим ситуацијама и да разједини различите архитектонске објекте, чиме се у први план стављају познавање и вештина њене примене, од чега суштински зависи успешност хармонизације новог објекта са постојећим окружењем.ЛИТЕРАТУРА aspects of urban interpolation, it is evident that the most present are two opinions.The first, which claims that regardless of the environment, the introduction of modern architectural layer in the existing context is extremely important, which most often results in contrasting interventions (Mitrović, Šverko, Stanković Simčić, Bulimbašić, etc.).The second opinion stresses wariness and a certain dose of respect for the existing surroundings, provided that the author does not wander off too far into imitation of the existing architecture (Brolin, Idrizbegović, Zgonić, Kurtović, Folić, etc.).The least present and seemingly the least favorited by authors is the opinion that in certain situations, when esthetically and historically valuable architecture is concerned, mimetic approach can be of great importance in deciding which approach to utilize when integrating a new object into the existing setting.Thus, it can be concluded that each creative approach in the decision process is equally valuable and deserves equal consideration in construction, although it is necessary to stress that the final quality of the work does not depend on the selection of a certain creative method, but more on the ability to utilize that approach.The paper also stresses the importance of the "bond" as an element that can visually connect, but also in certain situations disjoint different architectural objects, which stresses the importance of skill and knowledge related to the use of bonds, as the success in harmonization of the new object with its surroundings depends largely on these aspects.Author's archive.Tab. 1.
Fig. 6.Characteristic interpolation examples of "direction as bond" Fig. 7. Characteristic examples of object interpolation by adjusting the height of roof cornices Fig. 8. Characteristic examples of object interpolation by adjusting the structure of the facade elements