Phenomenal Transparency in Architecture : The case of Victor Horta

Phenomenal Transparency in Architecture : The case of Victor Horta Malvina Apostolou To cite this version: Malvina Apostolou. Phenomenal Transparency in Architecture : The case of Victor Horta. ICTA 2016- International Conference on Transparency and Architecture-Emerging Complexities, Nov 2016, Thessaloniki, Greece. pp.310-319. ฀halshs-01798534฀ HAL Id: halshs-01798534 https://halshs.archives-ouvertes.fr/halshs-01798534 Submitted on 23 May 2018 HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. Phenomenal Transparency in Architecture : The case of Victor Horta Malvina A. Apostolou Ecole Nationale Supérieure d' Architecture de Paris la Villette, CNAM [email protected] Abstract The object of this paper is to demonstrate the means of implementation of phenomenal transparency in the architecture of Victor Horta. More specifically, the buildings studied are the Hôtel Tassel (1893-1894), the Hôtel van Eetvelde (1895), and the personal residence of Victor Horta (1898-1901), in the city of Brussels. According to the definitions that have been attributed to the concept of phenomenal transparency (originally by Colin Rowe and Robert Slutzky in Transparency : Literal and Phenomenal) the paper seeks to understand the term and its connection with the architecture of the three works of Victor Horta, after the study of each of them. The elaboration of work is based on field research, study, recording and mapping held after visiting these three projects in the city of Brussels. After having studied the notion of this metaphorical transparency a conclusion is drawn: the unfolding or the multiplication of the perceived size of the space, and finally the creation of the image (Eidolon). This is illustrated by the creation of new plans on the basis of the collected data that, to my point of view, intensify the existence of phenomenal transparency. These new, virtual plans, are produced after the capture of multiple viewings, interpenetrations and perspectives that were recorded. 1. PHENOMENAL TRANSPARENCY Transparent 1. Having the property of transmitting light, so as to render bodies lying beyond completely visible, that can be seen through. b. Penetrating, as light c. Admitting the passage of light through interstices open, candid, ingenuous easily seen through, recognized, or detected; manifest, obvious By the dictionary definition the quality or state of being transparent is a material condition - that of being pervious to light and air, the result of an intellectual imperative- of our inherent demand for that which should be easily detected, perfectly evident (...) 'Simultaneity', 'interpenetration', 'superimposition', 'ambivalence', 'space-time', 'transparency': in the literature of contemporary architecture these words, and others like them, are often used as synonyms.(1) (...) this twin concept of actual and apparent transparency appears above all to be a precise tool for the study of architecture. It distinguishes between Essence and Appearance in the concept of transparency, and refers to the relationship between Content and Form in architecture - and to the still enormous question of whether a building is, or whether it means.(2) Colin Rowe, Robert Slutzky and Bernard Hoesli define the concept of phenomenal transparency and distinguishes it from the state of the literal one. An interpretation of phenomenal transparency as a means of implementation in a work of art as well as a declaration of the ambiguity of transparency is defined by Georgy Kepes in The Language of Vision : If one sees two or more figures partly overlapping one another, and each of them claims for itself the common overlapped part, then one is confronted with a contradiction of spatial dimensions. To resolve this contradiction, one must assume the presence of a new optical quality. The figures are endowed with transparency ; that is, they are able to interpenetrate without an optical destruction of each other. Transparency however implies more than an optical characteristic ; it implies a broader spatial order. Transparency means a simultaneous perception of different spatial locations. Space not only recedes but fluctuates in a continuous activity. The position of the transparent figures has equivocal meaning as one sees each figure now as the closer, now as the further one.(3) In Vision in Motion, Laszlo Moholy-Nagy indicates that (...) superimpositions overcome space and time fixations and unite strange and diverging subjects into new entities. They transpose insignificant singularities into meaningful complexities; banalities into vivid illumination. The transparent quality of the superimpositions often suggest transparency of content as well, revealing unnoticed structural qualities in the object.(4) We therefore observe that the transparency can be an inner quality of the materiality, or an inherent organisational characteristic/quality. Thus we distinguish literal and phenomenal transparency. Il its latter situation, as a quality of the organization, transparency is the sense of continuity of the void, a visible continuity through successive opaque volumes (5). The depth could be visible, or the volumes could be overlapped in one of their parts. A characteristic of transparency in its metaphorical sense is that the position of the individual forms in space is ambiguous: the eye is experiencing an infinite sequence of larger and smaller organizations within the whole. In general, transparency is generated where there are parts in the space that can be attributed to two or more systems of reference- where the classification is undetermined. The realities of the deep and narrow space are constantly in contrast. Gyorgy Kepes, while studying the representation of depth by overlapping figures notes that if one spatial form obstructs our view of another form, we do not assume that the second ceases to exist because it is hidden. We recognize, as we look at such overlapping figures, that the first or uppermost has two spatial meanings -itself and beneath itself. The figure which intercepts the visible surface of another figure is perceived as nearer. We experience spatial differences or depth. Representation of overlapping indicates depth. It creates a sense of space. Each figure appears parallel with the picture-plane and tends to establish a receding spatial relationship.(6) A typical characteristic is the insertion of the axis, the most powerful means for capturing the spatial depth: a linear axis penetrating the composition. Transparent organizations implicate spatial transitions and indicate the existence of possible directions. Therefore, the observer may perceive himself in relation with the both reference systems. The choice for one or the other path also means an entry in one or the other layout. Thus, he does not remain an uninvolved observer but becomes a part of the composition, through his participation he introduces a dialogue/relation and through his imagination he is involved in the reading of the composition. A continuation of the void, enabling the vision in the depth, and in a differentiated way as the observer moves (...) That is, the space, with that quality of organization of volumes enters into it and makes part of it, the time, which has to do with the movement of the observer.(7) Finally, as Colin Rowe and Robert Slutzky point out, (...) the intimations of depth (...) are consistently retracted. (...) a displacement, and a sliding sideways occur along the line of its minor axis; (...), an argument between a real and deep space and an ideal and shallow one.(8) (...)these stratifications, devices by means of which space becomes constructed, substantial, and articulate, are the essence of that phenomenal transparency (...)(9) Transparency therefore creates multiple readings of spatial relationships and their connections. It allows a flexibility in the organization of the composition. The connection between the space of two separate levels/planes result not only in a visual increase of the size of small spaces but also produces ambiguous spatial relationships: the spatial zones are differentiated and at the same time combined, united. Consequently, transparency as a means bears the possibility of optical spatial groupings. According to Bernard Hoesli, transparency is defined as a state of relationships and may be considered and used as a means of spatial organization. As soon as we see and understand solid and void as equally participating in or equally constituent of a figure-ground continuity it is no longer necessary to insist on their perceptually antithetical nature.(10) This limit is the dividing line, the dividing plane, the separating volume beyond of which something new begins. It is the border. (...) While passing from one area to another the user acquires different stimuli because of the different properties that govern each area. (...) The most common type of limit is (...)the opaque, which does not allow the light to pass through it. (...) The absence of a compact, opaque barrier does not imply the absence of limit. The void, the absence of matter can produce an equally strong limit (...) Unlike opaque boundaries, the transparent ones does not clearly define the relationship of the in / out, the up / down, but generate interesting commentary, which depends on the perception and the position of the observer in relation to them.(11) The spaces that are separated by glass partitions can be perceived as single (...) Because of transparency, these limits have as distinctive characteristic the sense of absence of matter as well as the unhindered diffusion of light. (...) (...) The separation in / out and is blunted and a sense, illusion of continuity, extension of space is created.(12) As three different, complementary ways of implementation of transparency, which does not always refer to the use of glass, can be considered the fluidity, the porosity and the glare. 'These three ways refer to multiple complementary concepts of transparency, permeability, perforation and translucency.(13) Translucency operates creatively in the space. It gives the illusion of an open or respectively enclosed space, depending on the reading made by the user. (...) A characteristic of translucency is its function as a filter. The information diffused through the translucent boundaries are susceptible to different readings, since they are not clear but blurred.(14) The element that is behind the other side activates the imagination and generates multiple readings. The combination of the concepts of inside, outside, up, down, forward, backward, diagonally, closed, open, full, empty is redefined, as well as the relation between line - point - level and surface and volume. 2. READING THE PROJECTS OF HORTA THROUGH THE NOTION OF PHENOMENAL TRANSPARENCY After the comprehension of the organisational structure of Victor Horta's three projects I intend to attribute them notions included in the Phenomenal Transparency- as described by Colin Rowe and Robert Slutzky in their article Transparency: Literal and Phenomenal as well as the characteristics attributed to transparency by L. Moholy Nagy and G.Kepes mentioned above. I attempt the finding of elements in the interior as well as the exterior part of the buildings, that are related to the superimposition of visual depths, the layering of levels and the fluidity of spatial parties. Thus, meanings of the term of phenomenal transparency are being attributed to the projects selected; the research attempts to find elements that are associated with the notions of superimposition, interpenetration of visual field, the overlay of levels of depths as well as the successive layering. Aiming at comprehending the characteristics that bear the impression that the building is of a bigger surface and amplitude, I am led to a classifications of the categories that intensify the relation with the spatial cognition after the in situ study of the houses and the architectural promenade in their interior. After a visit of the three selected projects, that are in situ meticulously observed, studied and registered I grouped the following elements that intensify the state of phenomenal transparency: - Framings - superimpositions / Layering / Overlays of levels and depth / stratifications / interpenetrations - Semi - Levels/planes (optical axes) - Mirrors - Surfaces of glass in the interior space that reflect - Form or figure in a background (stained glass, skylights, drawings in the ceiling/floor/side walls, sculptures) - Light (omnipresent in various types of manifestations) Superimpositions / Overlays We understand parts of the space as extracts, as even if they are defined they cannot be detached from the whole. The totality of the composition remains present and simultaneous with the reading of its parts. A sequential stratification (layering) of elements (such as fine bearing columns or side walls) ultimately generate a single composition of alternating depth. There are many levels of depth; their creation depends on our position, their existence or not on our interpretation. While traversing the area, moving away or approaching an element, these images consecutively change, highlighting every time another frame. Contents-sections which although they may be perceived as independent, do not lose their integration in the totality to which they belong. When moving elements (such as doors, windows, sliding walls) close or open the field of view changes again, new superimposed views are added to the previous ones. The longitudinal axis which traverses the composition helps to maintain a stable trajectory around of which (through the diagonal axes or the elements that added or removed during the movement in the space) successive views are generated, consecutive frames that when superposed bear varying interpretations and readings. The space presents the characteristics of a fluid, where the inside, outside, the right, the left are alternated, diffused, appear or disappear gradually. Now the space can be read in many ways. The limits, although clear, no longer operate as strict points of a start or an end; sometimes they mingle, they blur, they are erased or signify new unities - spaces. The foreground, the intermediate and the background: the sightings of the scene generate narratives; the pictorial grids create various gradients of depth, frontality, perspective. It is as if the same spatial canvas imply pluralities of overlays. Transparency as a quality of organization produces overlays of smaller organizations inside the whole. Axes - semi levels The optical axes, whether longitudinal and traversing the composition from one end to another, whether diagonal, upside, downside or lateral, play a major role in the existence of the phenomenon of phenomenal transparency. Through the semi-planes, the gaps (voids), the vertical circulations, the axes alter the angles of views, and thus provide multiple simultaneous sightings (views). As a result, while moving or standing in the space, we perceive more than one situations, we witness many zones of the space, lateral, horizontal, vertical; we perceive more than one depths, we have simultaneous parallel supervisions of sections of space. The space in its whole becomes more fluid, boundless, plenty of points / elements that can be read, penetrated, crossed, continued. Even if someone is in the same place, the perspectives change according to the point of his view; the space is perceived and discovered differently. The spiral path of the body, the turn, the stop, the movement, the rest, the twist. The axis around which someone moves is his own self, while other perspectives as well, lateral, horizontal, are hooked like a joint, and the gaze follows them. Mirrors The attribution of large parts or entire walls to mirrors contributes again to an annihilation of the limits. The space loses its clear definition from the side walls, and the wideness of the space is doubled. The folding of space gives a sense of continuity, by provoking a virtual size to the space. When two mirrors are placed opposite to each other, the image of the space is multiplied to infinity, the limits are erased, giving their position to the endless, the continuous, the intangible. Translucent glass The use of translucent or reflective glass enables the occupant of the space, during both his movement and stance, to perceive again an increased wideness of the space, by feeling present and visible the image he just passed behind. The area is not multiplied here, but, being reflected gently, the limits are diffused, resulting in the expression of phenomenal transparency. The architectural analog thereof can be found in the material qualities of the glass, overlays that are generated by the reflections of light in translucent surfaces. Form in a background A form in a background removes the limit. It annihilates it. As if the gaze does not stand, but penetrates. The painted walls negate the side wall, they break the side bonds and continue as parts of the fluid composition, as parts of the spaces. Now there is no beginning nor an end. Everything coexist as a whole, one proceeds to another, gets into the other, comes out of the other, diffused in all directions and blended with the facade, with the openings, the staircase, the floor, the ceiling. Here as well each form in a background is a separate abstract and can be read as such, but at the same time is integrated and inseparable from the rest. It is important to note that the state of a form in a background creates an endless impression. Light The light can be perceived here as a unifying factor of the space. Being omnipresent in the house, moving from the side on the road to the back one and the garden, following vertical paths through the skylights on the roofs, horizontal through the glass surfaces of the interior partitions, lateral through the semi-levels, carrying a variety of qualities through reflections or light spillovers due to materials, it flows with the space. It is born in the heart of the home, but is consolidated with the outside. Its different expressions through close and open levels define different realities in each subspace. 2.1. Phenomenal Transparency at the Hôtel Tassel (1893-1894, 6, rue Paul-Emile, Brussels) At the Hôtel Tassel, depths are alternated within the limits of outlines; sequentially the depth is diffused to the outside. The depth is present on each alternation. It is recorded in the successive overlays as part of the longitudinal axis that penetrates the plan and defines the composition - as well as vertical ones. Superimpositions As entering the house after passing through the entrance hall the visitor is located on the octagonal lobby. From here, through the main longitudinal axis, the hole depth of the house is visible, until the dining room and the garden. At the same time, through the two openings with stained glass on the right and left side, the visual field is widened through the diagonal axes. After ascending the seven steps, the view of the depth remains present, through the longitudinal axis ; through the two diagonal axes the width of the house is perceived, from one to the other side wall. Here the visitor is located at the intermediate space which is the preamble of the living room. In the sequel, while situated in the living room, through the longitudinal axis the one continues to perceive the depth, which gradually diminishes. This space is at the same time the preamble of the dining room while here the entire width of the house is perceptible. Finally, in the dining room and the end of the longitudinal axis, the width narrows, the depth is delimited to the garden. (figure 1) Following the reverse path of the longitudinal axis, from the dining room to the entrance, we find four such overlays: In the living room, while looking towards the entrance of the house, the visitor distinguishes three levels of depth on the longitudinal axis (the perforated limit of the living room, the smoking room, the entrance) and through the diagonal axes the wideness of space is expanded. In the steps that lead to the level of the ground floor the depth gradually subsides. Diagonal perspectives also exist. In the widthwise axis at this point, the visitor has an enlarged view through the diagonal perspectives. During the ascent to the first floor, at the level of the doorstep, a lateral view leads to the smoking room and, while being in it, the longitudinal axis and the two diagonals are dominants. Axes In the section, on the levels of the ground floor and the elevated ground floor the longitudinal axis that penetrates the house is dominant. By inserting the semi level of the smoking room, two diagonal axes are being created between the semi level, the elevated ground floor and the ground floor. (figure 2a, 2b) Mirrors The side wall of the greenhouse is partially covered by a mirror which starts from the visual level of a human occupying the entire width of the greenhouse. As a result the width of the house is multiplied ; the visitor perceives it as a folded space, as well as a part of the living room because of its glass limit with the intermediate space between the greenhouse and the staircase. Reflections The surface of perforated glass which defines the living room creates reflections of the previous space, by projecting him in the following one; as a result the perception of the space is slightly enlarged. Form in a background When entering the house, the reception hall is defined by a double door with stained glass. The area of the octagonal vestibule has on its both sides openings with color glass. Also, the smoking room is surrounded by stained glass, as the wall of the greenhouse in the first floor. On the ground, the hall and the octagonal vestibule, the forms can be read autonomously by defining each area, but also as a unity, emphasizing the fluidity and interpenetration of the spaces. These forms remain in the background of the side walls, the walls of the staircase, the greenhouse, the side walls of the floors. The two spaces that carry the light in the heart of the house (greenhouse and staircase) are covered with slightly colour glass. Finally we highlight the existence of the statue of David, at the level of the doorstep of the main staircase. Light As far as the movement of the light in the building is concerned, it is implemented through the longitudinal axis, vertically through the axis of the staircase and through smaller transversal axes. On the ground floor, the light circulates in the space through the stained glass of the entrance hall, the glass wall of the living room and the dining room and through the ceilings of the greenhouse and the staircase. In the first floor, through the office door, the stained glass of the greenhouse and the staircase's roof. At the last levels, the light is present via the axis defined by the greenhouse, the intermediate space, the staircase. 2.2. Phenomenal Transparency at the Hôtel Van Eetvelde (1895, avenue Palmerston 4, Brussels) At the Hôtel Van Eetvelde the standstill at different points of the space defines levels / parts : the back, the intermediate, the front. However, at the same time one can read the depth, which is present in each case. Every level has a contour - it is clearly defined, but also read as a whole. The eye stops in smaller unities - one being inside the other - without interrupting the whole. It is in fact successively superimposed excerpts that are located behind or in front of others. The foreground, the intermediate and the background are simultaneously superimposed. Superimpositions The movement in a diagonal axis during the gradual approach of the greenhouse generates alternating layers of depth. In addition, in the level of the first floor, because of the permeability of the longitudinal axis and the existence of the semi level of the greenhouse, successive superimpositions of levels are created, depending on our position. As someone enters the house, he finds himself in front of three depth levels: this that leads to the service areas, the intermediate of the greenhouse, and the foreground.(figure 3a) In The middle of the diagonal path he approaches the level of the greenhouse.(figure 3b) In The middle of the staircase he gradually acquires a view of the width and depth of the house. (figure 3c) In the greenhouse's level, the full overlap and interpenetration of the spaces on the first floor and part of the ground floor is perceived. (figure 3d) Gradients of layers and depths are visible in the living room where the gaze has contact and penetrates into intermediate layerings while having simultaneously contact with the depth.(figure 4) In the intermediate space before the dining room, and at the landing of the main staircase. Furthermore, a double row of columns in the living room and the dining room create small entities/unities within the whole. Axes The longitudinal axis penetrates the house from one edge to edge another. In the section also, due to the existence of the semi-level of the greenhouse, diagonal axes are created (ground floor, greenhouse, first floor). Furthermore, the vertical axis is present in the centre of the octagon. Mirrors In the Hotel van Eetvelde mirrors that occupy the spaces from one edge to another are absent. However, two mirrors of significant size are situated on the side wall of the living room and the dining room on the first floor, contributing again to the unfolding of the space the strengthening of phenomenal transparency that characterizes him. Reflections Glass walls defining the living room of the first level slightly reflect the area contributing to its penetration in the area of the octagon that follows, while also increasing the size of the living room by erasing its limits. Form in a background The stained glass of the dining room's door and the spaces enclosed around the octagon, the floor and the walls of the greenhouse, the ceiling and the walls of the living room and the dining room unify the parts of the space by implying their fluid relations . At the same time, the limits are annihilates the sense of the wideness of the space increases. Light The existence and propagation of light takes place through the longitudinal axis, as well as through three vertical ones. On the ground floor, through the glass walls; in the semi-level through the ceiling; on the first floor through the glass walls of the living room, the stained glass of the dining room, the ceilings of the two staircases; on the second floor through the stained glass situated around the central octagon and the transparent parts of the door. Finally, on the third floor blurred glass surfaces around the octagon and crystal parts in doors contribute to the unobstructed flow of the light in the house. The horizontal and vertical flow of the light from one edge to another in the interior of the house joins with the exterior, through the openings to the garden and the road. The inside and the outside are consolidated through the lighting and the ventilation. 2.3. Phenomenal Transparency at the Residence and Atelier of Victor Horta (nowadays the Horta Museum) (1898-1901, 23-25 rue Américaine, Saint-Gilles, Brussels) In the personal residence and atelier of Victor Horta the visitor is part of the vertical axis that leads to the end of the route, of the promenade in the interior of the building. The light is omnipresent during the movement. Beyond the iron thin frame and the light shades, he finds the sky, endless, deep. Superimpositions In this house the successive superimpositions of levels are generated during the ascent through the staircase that plays the role of an articulation of the individual spaces. Here there are not simultaneous penetrations of depths but individual chapters - extracts diffused through each other; as a result the space is perceived as continuous and fluid. Axes The basic axis that constitutes the phenomenal transparency at the residence of Horta, is the vertical spiral axis of movement. (figure 5) As the body follows the axis at every turn or stop, new views are added to previous horizontal or lateral ones, revealing at the same time many spaces. The longitudinal axis is also important, while penetrating the composition. Here we do not have floors, but semi-levels : this results at a constant expansion of the optical perspectives and reveals multiple views. (figure 6) Mirrors In his personal residence Horta has predicted mirrors in almost every room, through which the wideness is intensified. However, significant multiplications of the surface or unfoldings do not occur in every room that has a mirror. In the bedroom of Horta on the second floor and in the dressing room, the mirror occupies the whole defined space, thus creating an illusionary doubled space. Furthermore, on the third floor, in the bedroom of his Horta's daughter, Simone, a similar space unfolding is taking place. Finally, the most important virtual increase of size occurs in the last level of the house, with the two mirrors that are placed opposite each other, under the roof of the skylight. They reflect the image to infinity, producing an endless virtual unfolding. Reflections In the dining room of the first floor and in Horta's bedroom, the glass walls that define the rooms reflect slightly parts of the space, helping to create a sense of liquidity between the annihilated limits. Light The light, an integral component of the phenomenal transparency of this resident as a unifying factor of its individual spaces, is circulating through the staircase which like a backbone diffuses light in all the parts/semi levels with which is being articulated. 3. CONCLUSIONS Victor Horta was a pioneer of his times. He redefined the use and combination of new materials, the architectural solutions in the ordinary plots of Brussels and re-approached the classicist teaching of the School of Fine Arts of Paris; his architecture was a comment upon a changing society. His architecture was not part of a style or a trend; it was integrated into the movement that was reflecting the research of the artists of the time: it had a solid structure, expressed through logic and the feeling, through a comprehensive treatment, understanding and practice of architecture, construction and decoration art. The curves of the external skin of his buildings are interwoven with those of the internal; the structural elements and construction details with the charm of the forms. Through the research on the three projects of Victor Horta, the Hotel Tassel, the Hotel van Eetvelde, and his personal residence with the atelier (Maison Personnelle et Atelier), the following conclusions can be drawn concerning the structure and the laws governing his architecture and their connection with the phenomenal transparency -from the synthetic solutions and the function, until the doubling of space and the creation of Eidolon within the limits of an oblong plot. The staircase as a source of light and articulation of the semi-levels/planes, the light and ventilation, that is the literal transparency of the building, is a basic idea of Horta compositions. The unity and continuity of the whole is also a vital component of the architecture of Victor Horta: the transition and fluidity from inside to outside, from outside to inside, from the part/section to the entity, from the individual to the part and the part to the whole, from the detail to the total. Through the ongoing interpenetrations, superimpositions, the side walls and the semi-levels Horta annihilate the boundaries and lead to the passage from reading the composition via the literal transparency, to experiencing it through phenomenal transparency. The perceived size of the space is doubled or multiplied endlessly, through its virtual complementary and finally lead to the creation of the Eidolon, based on plans drawn up by the on-site mapping of various views, alterations of depths, interpenetration and reflections. Keywords: Victor Horta, architecture, phenomenal transparency Figures figure 1 : the superimpositions through the optical viewings, during the promenade in the elevated ground floor of Hotel Tassel. Because of the side walls/partitions the gaze escapes through the corners. figure 2a : By inserting the half level/plane of the smokehouse at composition, two lateral viewing axes are created on the ground floor level: one can supervise the two rooms simultaneously. figure 2b : The axes that penetrate the Hôtel Tassel are longitudinal (in each mezzanine), diagonals (due to the smokehouse's semi level, and the vertical axis of the staircase. These axes create horizontal, vertical and lateral sightings as well as superimpositions and successions of depths. figure 3 a, b1, b2, c, d : during the promenade in the Hôtel van Eetvelde from the ground floor to the octagonal living room, through the longitudinal axis and the lateral perspectives various superimposed sightings are created. figure 4 : With the presence of virtual transparency the space can be read in many ways. The limits, although clearly existing, no longer operate strictly and therefore signify new modules. This sequential stratification (layering) of elements (such as bearing columns) generate a composition of altering depth. There are many levels of depth, their creation depends on our place, their existence or not of our individual interpretation. While moving away or approaching the composition, these images consecutively change, highlighting each time another frame. Here are presented superimpositions of frames and depths as recorded during the in situ visit of the Hotel Van Eetvelde. figure 5 : the main axis constituting the phenomenal transparency is the vertical axis. Various sightings, horizontal and lateral are interpenetrating during the twist of the body. figure 6 : The personal residence of Horta is not constituted by floors, as by half-planes or parts of semi-levels and thus intensifying the phenomenal transparency. References 1. Rowe, Colin, Slutzky, Robert (1963), Transparency: Literal and Phenomenal, first published in Yale Architectural Journal Perspecta, Vol. 8, Reprinted as Transparency, Hoesli, Bernard (1968), Basel: editions Birkhaser, p. 160 2. Hoesli, Bernard (1968), Commentary in Transparency, Basel: editions Birkhaser, p. 59 3. Kepes, György (1944), The Language of Vision, Chicago: Paul Theobald and company, p. 77 4. Moholy – Nagy , László (1947), Vision in Motion, Chicago: Paul Theobald, p. 210 5. Andreadou, Tatiana (2002), Transparency a quality of matter, transparency a quality of organization, in Balkan Conference in Transparency and Architecture, 24-25 May 2001, Conference Proceedings, Thessaloniki, p.35 6. Kepes, György (1944), The Language of Vision, Chicago: Paul Theobald and company, p. 76 7. Andreadou, Tatiana (2002), Transparency a quality of matter, transparency a quality of organization, Balkan Conference in Transparency and Architecture, 24-25 May 2001, Conference Proceedings, Thessaloniki, p. 43 8. Rowe, Colin, Slutzky, Robert (1963), Transparency: Literal and Phenomenal, first published in Yale Architectural Journal Perspecta, Vol. 8, Reprinted as Transparency, Hoesli, Bernard (1968), Basel: editions Birkhaser, p. 175 9. Rowe, Colin, Slutzky, Robert (1963), Transparency: Literal and Phenomenal, first published in Yale Architectural Journal Perspecta, Vol. 8, Reprinted as Transparency, Hoesli, Bernard (1968), Basel: editions Birkhaser, p. 175 10. Hoesli, Bernard (1968), Excursus on the concept of architectural space in Transparency, Basel: editions Birkhaser, p. 91 11. Papaioannou, Kostis, Daskalaki, Filitsa (2007) The perception of limits, transparency-opacitytranslucency in Transparency and Architecture Limits and Challenges, Aristotle University of Thessaloniki, Faculty of Engineering, Department of Architecture, Thessaloniki: Ziti editions, p. 371372 12. Papaioannou, Kostis, Daskalaki, Filitsa (2007), The perception of limits, transparency-opacitytranslucency in Transparency and Architecture Limits and Challenges, Aristotle University of Thessaloniki, Faculty of Engineering, Department of Architecture, Thessaloniki: Ziti editions, p.375 13. Konstantopoulos, Ilias (2007), The blur, the fluid and the porous: Building with Transparency in Transparency and Architecture Limits and Challenges, Aristotle University of Thessaloniki, Faculty of Engineering, Department of Architecture, Thessaloniki: Ziti editions, p.434 14. Papaioannou, Kostis, Daskalaki, Filitsa (2007), The perception of limits, transparency-opacitytranslucency in Transparency and Architecture Limits and Challenges, Aristotle University of Thessaloniki, Faculty of Engineering, Department of Architecture, Thessaloniki: Ziti editions, p.377 .