Archive for August 25th, 2010

August 25, 2010

Green Architecture at the California Academy of Science

California Academy of Sciences

infographic by Bryan Christie Design

Renzo Piano’s California Academy of Sciences is a home for flora and fauna — and a feat of engineering.

In 1999, the California Academy of Sciences, eager to replace its quake-damaged building, invited six architects to submit designs for a new home in San Francisco’s Golden Gate Park. The facility had to accommodate 38,000 live animals, 20 million specimens, and 2 million visitors a year — and meet lofty environmental goals.

Five architects arrived with intricate models. Renzo Piano had only a pad and a felt-tip pen. After days of talks and walks in the park, he climbed onto the Academy roof, gazed at San Francisco’s hills, and came back down with a winning design: a wavy green line. “The idea was to make the roof like a flying carpet, a piece of the park flying,” he says. “If you fly over the park now, you don’t even see the building.”

The disappearing act took 320 engineers from the design firm Arup to orchestrate. “When we drew all those curves, I knew that was going to be a great challenge,” says Piano. (So great, in fact, that the Discovery Channel’s Extreme Engineering did an episode on the project.) The biggest conundrum: how to support the glass over the central piazza, because Piano refused to let columns break up the space. The answer came, of course, from nature — a spiderweb of cables now holds up the glass.

Piano’s $488 million vision opens to visitors on September 27.

August 25, 2010

Flying Carpets; The Floating Roofs of Renzo Piano Building Workshop


Philadelphia University

The buildings designed by Renzo Piano Building Workshop (RPBW) consistently demonstrate a clear efficiency of design.  In fact, a major goal of Piano’s design process is to make “one move to do many things”1 as often as possible.  In this way each element or system of construction provides many functions, both physical and conceptual.  This is clearly evident in the design of the lightweight, seemingly hovering, flat roof assemblies that he refers to as “flying carpet” roofs.  His fondness for this roof type is evident by its multiple replications in his projects over the years.  Each flying carpet roof is an integral part (often the key part) of each building design and provides an array of functions to justify its complexity and expense.  For one example, the flying carpet roof on the building in Milan for the Italian business newspaper Il Sole 24 Ore (Il Sole) provides many physical and conceptual functions at once.  It is a major shading element for the top floor balconies, it provides railings to support the window washing equipment, it responds to the context by matching the height of surrounding buildings, it provides a structure light enough to be supported by the existing concrete frame, it defines the perimeter boundary of the building to conceptually tie the large complex together, it provides a clear capital to the tripartite order of the exterior and it helps blur the distinction between inside and outside space.   All of RPBW’s flying carpet roofs perform these multiple tasks in various ways depending on the use of the building.  For this paper I analyze four buildings that utilize this type of roof: Il Sole, The Cy Twombly Gallery in Houston (Twombly), the Beyler Foundation in Switzerland (Beyler) and the Chicago Art Institute addition (Chicago) currently under construction. I compare their similarities and differences in 4 categories of Operational, Material, Compositional and Organizational.

OPERATIONAL – Modulator of Light

With each of the four roofs, the primary reason for their design, and therefore deserving of the most discussion, is the control and modulation of sunlight from above. This is especially important since the three museums have strict requirements on the amount of direct and indirect sunlight allowed into the galleries. “Many lighting trials have demonstrated, once again, that overhead light is the best way to give the works softer and more natural colors.”2 To allow abundant quantities of natural light without the accompanying ultraviolet damage and glare, Piano has created many distinct overlapping layers of sun-control elements that create a multi-layered sandwich of louvers, shades and screens to bounce and filter light.  Although he has experimented with light control in roof design before, the real genesis of the multiple layer “flying carpet” roof was RPBW’s de Menil Museum in Houston where “light was used consciously to dematerialize the space, creating the necessary concentration on the works of art.”3 While this roof performs in a similar way to the other roofs, it is not as compact and integrated as the others and therefore is does not fit the description of a flying carpet as well.  The de Menil roof clearly displays all the sun shading, enclosure and structural systems in a thick band at the edge of the building. In this building the glass is the top layer, a structural truss is in the middle and light controlling lovers are suspended below.  This ordering system of layers has been compared to Sverre Fenns’s Venice Biennale Pavilion where a translucent skylight sits on overlapping concrete fins that perform both as structural beams and light reflecting louvers.4 However, in the three other museums, only one thin band of a shading element is revealed at the building face thereby providing the roofs with their flying carpet imagery.  To achieve this, the ordering of layers is reversed from that of de Menil, with slight variations for each so that the louvers hover above the walls and the glass and much of the primary structure are hidden behind the walls.  To get a better understanding of these complex details, I redrew a detailed, color-rendered section through each of the three museum roofs to delineate the specific materials and connections. (see appendix)  Through this study I was able to identify the similar layering strategies.

The layering order follows this general pattern:

1. A top layer of fixed diffusing louvers, either in metal or translucent glass.

2. A middle layer of a sealed glass envelope used to keep out wind, rain and sun.

3. A bottom layer of a translucent ceiling of either stretched cloth or perforated metal used to diffuse the light to an even glow.

There are then variations between the museums. Twombly and Beyler have an extra layer of mechanically controlled adjustable louvers located below the glass layer to add an additional level of light control.   Beyler also has an additional lower glass ceiling mainly used as an air cavity thermal buffer rather than a light control device. Chicago does not have an additional middle layer of louvers but this may be because the shape of the top louvers is far more complex than the simple bar grating of Twombly or the sloped glass panels of Beyler.  These both work effectively to control southern light but are less effective on east and west sunlight so the louvers at Chicago have incorporated a vertical fin on the back of the main louver to block low-angled light. The overhang of the top louver system at Chicago is also much deeper than at Twombly thereby protecting more of the skylight below.  Twombly must compensate for this by adding extra sun protection to the glass itself.  “Because the upper canopy of fixed louvers does not over sail the exterior walls, direct sun falls on the lower and outer edges of the glass.  In these places it is fritted (at between 20 and 80 percent depending on location) to limit the amount of direct sun admitted.”5

The four layers of light control may at first seem like overkill; but they are in direct response to strict illumination requests from the client. “The Cy Twombly gallery houses a permanent collection so the works are much more vulnerable to damage by light. Consequently the level of illumination is lower and constant; 300 lux as opposed to 1000 in the (de Menil) museum.”6 While the layering is intricate and the technology complex, Piano does not try to draw attention to the roofs themselves.  Instead he conceals most of the details behind the translucent ceiling and lets the roof do its job.  “The air of modern technology, which the roof construction brings to the building, focuses on using natural light to illuminate the art objects below and is hardly perceived by the visitor.”7 By reversing the order of layers of de Menil, less sun penetrates the glass so cooling loads and ultraviolet damage are reduced and the roof takes on a more elegant role as a cap to the building; an idea to be further discussed later.

After noting these differences in each of the louver systems, it is important to trace their development over time.  Starting with the de Menil and progressing through the Twombly, Beyler and Chicago, there is an interesting cycle of development of the sun shading system.  The de Menil had just the one large-scale concrete louver system.  To better control the light in Twombly, a four layer system was created with metal louvers on top above fritted glass with a mechanical louver system and a stretched fabric ceiling system below.  As was aforementioned, there was still a problem of low-angled light leaking in at the edges so for Beyler, four layers of protection were again provided but with more protection at the edges from an overhanging eave.  Similar to Twombly, the top layer is of large translucent glass louvers above a layer of fritted glass with mechanical louvers and a perforated metal ceiling below.  For Chicago, RPBW has returned to a simpler shading system reminiscent of de Menil.  If my research is correct (barring construction changes) and there is no fritting on the glass skylights, then there are only two means of shading in this building, a layer of metal louvers on top that can control light from all directions and a stretched fabric ceiling below.  In this latest building the architects seem to have learned how to control light without the need for elaborate mechanically controlled systems thereby reinforcing their goal of making one system perform many functions.

Since Il Sole is an office building and not a museum, light control was not as critical. However by looking at sketches of the preliminary design, we can see how it still followed the same pattern of the museums. Originally there were more layers planned for the roof but got removed in budget cuts.  A field of photovoltaic panels, arranged in a shed roof pattern similar to the top glass panels on the roof of the Beyler, was to cover most of the roof.  Beyond supplying a source of electrical power, they would have added another sun shading layer to the roof composition.  Having less stringent shading requirements at Il Sole allows more light to filter through and therefore has the benefit of a pleasant light quality, like the dappled effect found under a tree, cast onto the balconies and courtyard below.

MATERIAL – Weightlessness

“Anyone can build using a lot of material. If you make a wall a meter thick then it is going to stand up.  Taking weight away from things, however, teaches you to make the shape of structure do the work, to understand the limits of the strength of components, and to replace rigidity with flexibility.”8 Renzo Piano

“When looking for lightness, you automatically find something that is precious, and that is very important on the plane of poetic language: transparency.”9 Renzo Piano

Piano’s long documented interest in transparency and lightness is evident in the lacy, delicate quality of the flying carpet roofs.  The porous nature of the roof planes, that permit some but not all light to penetrate, adds to the sense that the roofs are hovering or flying above the supports below.  One of the first ways he emphasizes this sense is by contrasting the perforated roofs with a heavy base below.  At Twombly the walls are unrelieved reconstituted stone that give a monumental feel and at Beyler the walls are made of porphyry stone from Patagonia, the effect of which Piano has compared to a roman ruin. “The supporting structure is not visible from the galleries below, which creates a sense of lightness in clear and deliberate contrast to the rocklike solidity of the outside walls.”10 While some walls at the other 2 buildings are glass, both have significant areas of walls made of heavy compressive materials.  Il Sole makes extensive use of yellow brick and Chicago has walls of stone veneer.

The next technique to impart lightness common to all four buildings is the elevation of the roof plane clear of the supports below. At Beyler the roofs are suspended on pointed columns capitals above the walls to increase the feeling of separation. “You notice that the white fittings not only help unify the glass and steel, but also that its pattern and the slight slopes of the glass add a visual rhythmic energy that helps the roof fly free of the earthbound walls.”11 At the other three buildings, the roof is raised an average of about ten feet above the walls below creating a clear reveal of space between wall and roof. At Chicago, this effect is the most dramatic.  Not only is the roof raised the greatest distance above the walls below, it also extends out the farthest from the building perimeter as it “hovers over the building like a ships rigging”.12 This requires the roof edge to be supported on columns isolated from the perimeter wall.  Because the roof is perforated and has little live load from snow or wind, the columns can be especially slender.  The overall effect is one where the roof seems to be physically disconnected from the building while conceptually holding it all together.

RPBW also achieves a sense of weightlessness  through a practice of structural gymnastics.  To increase a sense of disbelief about how the roof is supported, they stretch the structural strength of steel and glass close to their maximum efficiency with little unnecessary material wasted.  Where possible, such as at Il Sole and Beyler, he extends the edge panels out past the last supporting beams to increase the sense of lightness as the roof seems to dissolve at its end.  “Above you see the oversailing roof float out to embrace its surroundings, supported on the crisp white steel grid and the glazing bars propped from this and stopping short of the ends of the glass sheets which reach out unconstrained by frames.”13 For the deep cantilevered roof over the interior courtyard at Il Sole, the main beams thicken upward as they get closer to the support point rather than downward as is typical for a cantilevered beam.  In this way the heaviness of the beams is screened and partially hidden from view from below thereby adding to the sense of structural curiosity and excitement as to how the roof is able to span so far.  Again, the minimum live load requirements of perforated louvers allows the structure to achieve a minimum thickness and thereby a greater sense of lightness.

COMPOSITIONAL – Roof as Capital

The lightness and perforated quality of the flying carpet roofs begs the question, do they belong more to the earth or the sky?  Probably a little of both.  Like a cloud hovering over the facade below, they crown each building to provide a graceful transition from wall to sky.  The classical tripartite order of base, shaft and capital has proven itself to work on both modern and traditional buildings. Piano understands this and takes advantage of it in these designs by using the roof to create a strong capital to each edifice.  While the Beyler has been compared to a Roman temple, I also see a comparison to another Italian building type, the renaissance palazzo with an open loggia on the top floor.  This is especially evident at Il Sole where, like at the palazzo, the top floor balcony recesses from the face to create a deep reveal and a lightweight roof cantilevers far out and around the corner of the heavy base below. Both create an aesthetically pleasing completion to the elevation and transition to the sky.

Another way the roofs act as a capital is through the use of intricate details created by the multiple layers of construction. The overlapping layers of louvers and glass mullions create intricate patterns that draw the eye upwards to the rich detail as the tryglyphs and metopes of a classical temple pediment might do. However Piano’s details are more honestly arrived at (by Modern architecture standards) as they are functional elements and not merely representatives of former construction materials and methods as in the classical temple.  Piano has written that he is interested in reintroducing the theme of ornament, not decoration, to architecture.  He writes; “I believe that architecture has to be given back its richness. It should show the mark of the person who made it, what Peter Rice calls the ‘trace of the hand.’ The quality of the building is also expressed through the quality of the detail.”14 Architects of modern buildings have long been wary of providing too much embellishment to their buildings as they feared being labeled traditionalists adding extraneous ornament.  However, the flying carpet roofs run little risk of being labeled extraneous as they have such clear and important functions of structure and climate control.  These precise instruments clearly reveal their function while simultaneously providing some visual interest for the viewer; another example of Piano’s objective to achieve multiple goals within one design.

ORGANIZATIONAL – The Sheltering Roof

A fourth commonality of the flying carpet roofs is the use of the roof as an overall unifying architectural enclosure that serves as an organizing datum for the spaces below.  This ‘mother hen’ effect is most clearly demonstrated at Il Sole and Chicago where the roof is used to clearly demarcate the main body and underlying order of the buildings.  The strict geometry of the roof steadfastly maintains the order of the project while allowing the walls below to move to accommodate programmatic functions.  At Chicago the perfect square plan of the roof is supported regally on slender columns while the building below extends inward and outward, to varying degrees, from the line of the roof perimeter.  Yet the strong square shape of the roof implies invisible boundary walls to hold the building together.  Since the project is yet another addition to the museum, there was a strong need for hierarchy, order and clarity for this new entrance, which the clear geometry and prominence of the roof helps provide.

The sheltering roof also blurs boundaries of interior and exterior space.  The roofs flow steadily and continuously, almost disregarding what is happening below.  For example at Il Sole, the roof soars over exterior balconies and courtyards, interior atriums, spaces between buildings and solid roofs without much change.  This creates some special ‘in-between’ spaces that feel like both interior and exterior spaces.  The quality of light created by the perforated nature of the roof greatly aids this effect which would have been less so under an opaque floating roof.  At Beyler the roof is decidedly directional but as it extends over the north and south sides and dissolves into garden, it soars past the glass curtain walls and over the water garden below with only slight modifications in its materials.  As such, the space below feels like it belongs to both the interior and exterior.

While initially created as practical mechanisms for the strict control of sunlight, Piano has developed the flying roofs into powerful design elements in their own right that have proven to be adaptable to many cultures and locations.  While their number of layers and degree of enclosure vary with the demands of each project, the general pattern of the flying carpet roofs remains consistent. Because the engineering of the roofs is not clearly visible, their role as sun screens is often over-shadowed (no pun intended) by the strength of their sculptural form. However one is not more important than the other as the roof systems incorporate operational, material, compositional and organizational aspects into a truly integrated design.  As they fulfill Piano’s goal of making “one move to do many things”, they are excellent examples that demonstrate the inseparable relationship between technology and design, something we are constantly striving to impart in our students today.


1 Conversation with Mauricio Cardenas, former employee of RPBW and team member of Il Sole


2 Piano, Renzo, The Renzo Piano Logbook, Thames and Hudson, London, 1997

3 Piano

4 Foundation Beyler, Editor, Renzo Piano–Foundation Beyler, A Home for Art, Birkhauser, Basel,


5 Buchanon, Peter, Renzo Piano Building Workshop, Complete Works Volume 3, Phaidon Press

Limited, London, 1997

6 Piano

7 Beyler

8 Piano

9 Piano

10 Piano

11 Beyler

12 Cuno, James & Thorne, Martha, Zero Gravity, The Art Institute of Chicago, Chicago, 2005

13 Beyler

14 Piano


Buchanon, Peter, Renzo Piano Building Workshop, Complete Works Volume 4, Phaidon Press Limited, London, 2000

Poletti, Raffaella, Renzo Piano Building Workshop-Nuovo Sede Per Il Sole 24 Ore, Il Sole 24 ORE, Milano, 2004

August 25, 2010

Chicago’s flying carpet

A world-class art museum in America turns to Germany, Italy and Belgium for expertise in fitting out its new, modern wing. It was Sapa RC Profiles in Belgium that produced the unusual aluminium arch profiles.

Germany’s Josef Gartner GmbH had plenty of experience when it came to building a project for the Art Institute of Chicago. The company has been producing and installing curtain walls for 140 years, mainly for large buildings. “Sealing the new, modern wing of the Art Institute of Chicago was a complex task,” says Klaus Lother, ceo of Josef Gartner. “But that’s the kind of job for us. We specialise in tailor-made work, using materials such as aluminium, steel and glass, as well as copper and bronze.”

“When it comes to production and construction of curtain walls, we don’t go for standard solutions,” Lother says. The company’s designers and engineers take the requirements of the customer and the architect and come up with an appropriate technical solution. “The modern wing of the Art Institute was a challenge because of the different types of curtain walls, the combination of designs and the different materials,” Lother says. “But it was a challenge that suited our expertise perfectly.”

Josef Gartner GmbH teamed up with Renzo Piano, the well known Italian architect whose projects include the Pompidou Centre in Paris and the Potsdamer Platz in Berlin. Josef Gartner had worked with Piano for a library in New York and the California Academy of Sciences. “Piano comes up with the design and makes the drawings, which we then take as a basis for developing our technical solution,” Lother says.

Sometimes the design poses unusual challenges, as in the case of the “flying carpet” above the Art Institute of Chicago. Its construction required aluminium arch profiles half a metre across and more than five metres long. Extreme precision was crucial for keeping the flying carpet perfectly smooth and streamlined. Any imperfection would be immediately apparent and would affect the light-regulating effect of the upper roof. “We have done extrusion work in the past, and I know how difficult it is to produce arch profiles with these dimensions,” Lother says. “The profiles must not deform after extrusion or during the painting process and further treatment.”

After the requirements for the arch profiles were known, Josef Gartner consulted possible partners and settled on Sapa RC Profiles in Belgium. “We have worked with them before, and know them to be exceptionally reliable and professional. Sapa RC Profiles produced the aluminium sections and also carried out the fabrication and surface treatment,” Lother says. “There was no deformation when they were painted after extrusion, so the flying carpet appears perfectly smooth and homogeneous.”

August 25, 2010

Renzo Piano

Alberto Losano


1. Who is Renzo Piano?

2. Renzo Piano’s themes
2.1 My Architecture
2.2 Genius Loci
2.3 Experimentation
2.4 Language

3. Renzo Piano’s sustainable Architecture
3.1 The Light
3.2 The Air
3.3 The Space

1. Who is Renzo Piano?

Renzo Piano was born in Genoa (Italy) on September 14, 1937. He graduated in 1964 from the school of Architecture of the Milan Polytechnic. As a student, he was working under the design guidance of Franco Albini, while also regularly attending his father’s building sites where he got a valuable practical experience. Between 1965 and 1970, he completed his formation and work experiments with study travels in Britain and America. It was at that time he met Jean Prouvé: their friendship would have a deep influence on his professional life. In 1971, he founded the “Piano & Rogers” agency with Richard Rogers, his partner on the Centre Pompidou project in Paris. In 1977, he founded “l’Atelier Piano & Rice” along with the engineer Peter Rice, a professional personality who would work with him on many projects, until his death in 1993. He then founded Renzo Piano Building Workshop, with offices in Paris and Genoa. Some 100 people work with him (among which architects, engineers, specialists…) in close collaboration with some associated architects, linked to him by years of experience.

2. Renzo Piano’s themes

2.1 “My Architecture”
“This has nothing to do with genius: it is experience. It is exactly the same as the skill of the expert fisher, or mushroom picker, or jazz musicians when they improvise. Artists are not people who have a gift; rather they are people who master a tekné”. “If the spirit of adventure is one of the driving forces in my work, another is certainly obstinacy. Obstinacy and tenacity are very important qualities, whether on the professional plane or the cultural one”. “Perhaps the secret is not to keep your dreams in the drawer. They have to be used. They have to be risked”. “When style is forced to become a trademark, a signature, a personal characteristic, then it also becomes a cage. The effort to be recognisable at any cost, to put your hallmark on things, kills the architect and his or her freedom to develop. The mark of recognition lies in the acceptance of the challenge. And then, yes, it does become identifiable: but by a method, not by a trademark . There is always a temptation for a young architect to start out with style. But I started with doing: with the building site, with research into materials, with the knowledge of construction techniques, conventional and otherwise. My journey through architecture started out from technique and has gradually led me to an awareness of its complexity as space, expression and form “. “Over many years of work I have come to the conclusion that so-called instinct, which is supposed to guide art and creativity, is nothing but a rapid process of synthesis, a turbocharged form of rational thinking. If I look at a plan I am much quicker on the uptake than someone else. I see what is important right away. But use it to attain their objective, which is art”.

2.2 “Genius Loci”
“I believe that the architect must lead a double life. On one hand is a taste for exploration, for being on the edge, an unwillingness to accept things for what they appear to be: a disobedient, transgressive, even rather insolent approach. On the other is a genuine, and not formal, gratitude to history and nature: the two contexts in which architecture has his roots”. “Discipline sets limits to freedom, yet it is also its container: the thing that gives it form. These two elements coexist and interact. In architecture it is the blank sheet that paralyses, not the constraints imposed by the context. The context is a resource; it is material to draw on, a score to be interpreted. Architectural invention cannot ignore history, tradition or the context of construction. It may decide to break with all that, but even then it has to take these influences into account, though in terms of opposition, of overturning”. “Architecture is a second nature that is laid on top of the real one. When people who practice our profession speak of the environment, they ought to remember this. To talk about the sustainability of architecture means understanding nature, respecting animals and plants, siting buildings and factories correctly, making use of sunlight and wind. To interpret the placeform, every project requires a specific study, a deep understanding of its history, geography, geology and climate”. “What interests me is shaping form and product together: forcefully sculpturing the land, leaving a deep mark on the pre-existing nature or urban structure; but, at the same time, making the architecture an accomplice, a partner, imbued with the characteristics of its surroundings”.

2.3 “Experimentation”
“We have to give our profession back its capacity to arouse the emotions by creating dramatic spaces, serene spaces, participatory spaces, secluded spaces. The choice is linked to the function and use of the setting. If you are designing a museum, you offer contemplation. It is not enough for the light to be perfect. You also need calm, serenity and even a voluptuous quality linked to contemplation of the work of art. If you are building a concert hall, it is not enough to provide perfect acoustics: you must encourage participation in the music. If you build a house, on the other hand, what you are aiming for is a sense of protection, of comfort. You have to create a feeling of intimacy and privacy for its occupants, but without excluding the world outside, nature, the city and people. The objectives change each time, but they always turn around the need to stir the emotions. “I believe that is very important to work with the immaterial elements of space and I am fascinated by this research. I think that it is one of the main currents in my architecture. Light, transparency, vibration, texture, colour are immaterial elements; they interact with the form of the space, but are not just a function of it”. “When you’re looking for lightness, you automatically find something else that is precious and that is very important on the plane of poetic language: transparency. Lightness is an instrument and transparency is a poetic quality. In the quest for lightness and transparency, there is a logical and poetic continuity”. “Natural light, often diffused from above, is a constant feature of my work. Light has not just an intensity, but also a vibration, which is capable of roughening a smooth material, of giving a three-dimensional quality to a flat surface. Light, colour and texture are part of a patient work in progress in my studio.

2.4 “Language”
” New technologies are bringing peoples and cultures into contact with an ease that is unprecedented in human history. I believe in the positive value of this possibility. What form will this language take? I can only express my hopes: what I would like it to be and what I would like it not to be. In part, it has to derive from problems that are new or perceived in a new way, such as those relating to the environment. The vocabulary of architecture translates all this into the use of plants, the choice of materials, the application of solutions that save energy. In part, it has to stem from the language of technology and science: the search for contemporary forms of expression cannot be divorced from technical innovation, perhaps the most characteristic trait of our civilisation and the one that has the most influence on the material culture of design. Above all, the new language has to respond to changing needs with a greater attention to the quality of life and work, and an awareness that the inadequacy of housing is the source of much of the malaise in contemporary society”.

3. Renzo Piano’s Sustainable Architecture

The works of Renzo Piano have a big importance for our time. He doesn’t follow formal or theoretical tendencies neither he limits himself into a typical personal language, but his approach is in the same time open and collaborative, in relation with the different sites and times. He interests himself in the phases and
in the techniques of construction as well as in the final form of the building.
The Renzo Piano Building Workshop tries to combine the “genius loci” and the local tradition with the possibility of the new technologies and materials. Though each project pushes the technology until the limits, it exalts and regenerates the historical context and the nature. This is an ecological, evolutionary and humanistic conception of the architecture, looking to the future considering the culture and the context.
In this way Renzo Piano gets closer to the sustainable architecture; every day, “pezzo per pezzo” ,step by step, in continuous and constructive challenges, from the details to the general.

3.1 The light

The first time that Piano gave to the light a particular role was working in the project of a museum of the surrealist and primitive African art collection of Dominique De Menil, sited in Houston. During a trip in Tel Aviv with De Menil, visiting a museum in the same latitude of Huston, arose the idea to make of light the main point of the new musem. The idea grew up and Piano studied a lot of different ways to utilize the zenithal light in the exposition halls. Accurate studies of solar angular condition, the filtering of ultra -violet rays, multiple reflections, ecc. were carried out with an appropriate solar machine. In addiction to these studies, experiments were made with several structural materials that have resulted in an element designed as a “Leaf”, which is a device for modulating both artificial and natural light. The aim of the design was to create a space facilitating a direct and relaxed relationship between visitors and exhibited objects, through the creation of a non-monumental and familiar environment in contact with nature.
Similar ideas to use the natural light were applied in the new building of the Foundation De Menil with the collection of Cy Twombly. More than ten years later Piano tries new ways, also technological, drawing an high tech roof with glass, iron deflectors and tissues for using the sun light.
It was decided early in the design process to make the roof look light in weight as butterfly wings and to have the artworks to be seen in natural light as in the main building, though the annex would have its own distinctive spatial organization. As a solution, several layers of roofing and ceiling materials are used to filter natural light.
First, fixed louvers are installed on the outside to remove direct light and solar heat. Slanting double-layered glass is used as roofing material to keep out rainwater, outside air and ultraviolet rays. Under the glass surface, movable louvers control the amount of the introduced light, and translucent cotton fabric used as the ceiling material in the exhibition rooms that disperses light. Round holes are punched in places in the ceiling material and make an artificial lighting possible as well. As in the main building, light follows a certain rhythm in the time changes. Natural light changes as air and clouds flow outside, and this dynamic quality of light endows the subtle artworks with a variegated appearance.

Other aspects of the utilization of the natural light were developed in some industrial buildings in order to give a good comfort for the work and to cut down expenses. One of the most interesting projects in this area are the Lowara Offices in Vicenza. Lowara is an Italian firm manufacturing electric pumps. Its new headquarter offices are conceived as an open space enhancing contacts among employees at work.
This principle is perfectly represented by an open work place where people can easily cooperate and compare their work without physical barriers.

The adopted assembly system lets the light flow in, thus increasing the sense of lightness of the building. The roofing is supported by a number of V-shaped steel columns. It is completely independent of the existing building. A simple corrugated steel sheet, normally used for bridge building, was adopted for the roof. The steel sheet is used as a form into which the concrete can be poured. It thus became part of the total structure itself and at the same time acted as inside finish to the ceiling. The upturned eaves running along the low elevation that faces the garden help to frame the view of the landscape with a Palladian villa in the background.
The natural light entering the building at this elevation is softened and amplified by the corrugated steel sheeting of the ceiling. Such a gently curving ceiling confers a richer quality on the interior environment. A reflecting panel was inserted into the gap at the top of the roof in order to soften the light coming from the south facing side to make a more pleasant corridor.
For the winter heating the air-conditioning supply duct runs high, thus exploiting the dynamic space created by the suspended form of the roof. The return has been obtained through the raised floor.
In the summer, the conformation of the inner space and the action of the wind on the
cover concur to produce a natural air ventilation for convection and sprinklers have been fitted along the roof edge (key element of the whole project) in order to cool it by evaporation.
An other example of industrial building is the Thompson Optronic Factory.
Thomson had to build a new manufacturing plant in the area of Saint Quentin-en-Yvelines, near Paris. A site had already been designated on which there were no constructions to reckon with; the environment itself was flat, shapeless, and not characterised by any particular vegetation. It was not possible to predict the division of functions with any accuracy; it was not even clear just how big the complex would eventually be, so he had to create a completely open space, a theme with which he was thoroughly familiar.
In this case, the basic module is a large arched element with a span of almost fifteen metres, which produces buildings with soft, curved lines. The interiors provide pleasant working conditions, thanks to the presence of greenery and the extensive use of natural light, also with several “reflection’s games” .
The landscape responds to the fluidity of the construction with the rigor of an orthogonal grid defined by lines of trees and other plants. Thus the buildings are given a logical setting by the ‘frame’ of the vegetation, as if they were placed on a checkerboard. The integration of architecture and nature is based on a respect for the same formal rules: future enlargements will need to do no more than follow them.

The Renzo Piano Building Workshop in Vesina(GE).
This laboratory for research and development of Mediterranean natural structures is a collaboration between the UNESCO and the Renzo Piano Building Workshop. Indigenous Mediterranean pines and olive trees, bamboo, mescal, corn, indian rubber tree plants and reeds are cultivated here for research purposes: the fiber structures and special properties of these plants are investigated and applied in construction. Studies also include biophysical research, development of inexpensive corrugate sheets, joining laminated lumber with other materials, and stone construction methods and techniques still used in parts of Italy and Spain, the study of earthen walls, brick and other common materials, and the research of new materials. In addition there is the investigation of the effects of -and the application of -acoustic, insulation and lighting techniques.
The site is in the Western part of Genoa, facing the Mediterranean Sea, being naturally terraced, running down a hill from the highway above to the coast line.
Situated along a slope ,the simple lab construction is made of laminated-lumber beams over thin steel. The wall toward the mountain is indigenous stone and earth construction; the three other facades utilize as much glass as possible, creating the illusion that the luxurious greenery growing inside and outside is lifting the roof of the structure above the slope.
The roof construction, comprises double glass, new materials, plastic, insulation panels, reflective cloth panels for indirect lighting; on the exterior a louver connected to a photometer and wind meter senses subtle changes in the climate and constantly adjusts the conditions inside like a living organism. The placement of and research with solar panels is being considered for the future. The interior floor is mainly wood, and Ardesia (black slate) paving from Liguria is used from the interior to the exterior.
The workshop is an immense greenhouse overtaken inside and out by all types of plants and greenery, creating the feeling of a privileged communion with nature. In the same spirit, the trial is to take maximum advantage of the zenithal light that pervades every aspect of local life and has rapidly become a natural clock.

3.2 The Air
J. M. Tjibaou Cultural Center, Numea.
Among the agreements reached in June 1988 by the French government and New Caledonia, on its way to independence, it was decided to build a Cultural Center in the surroundings of Noumea dedicated to the Kanak Melanesian culture and to name it after Jean Marie Tjibaou.
Drawing on a profound relationship with the nature of that civilization, Renzo Piano’s project followed two main guiding principles: on the one hand evoking the skill to “build” with and in the Kanak natural environment, on the other hand combining traditional materials such as wood and stone with modern materials such as glass aluminum, steel and soft advanced technologies.
In Renzo Piano’s words, it is “a work taking care of nature, a humanistic realization where history, architecture, archeology and social sciences are brought together.”The Cultural Center has been set up on a peninsula surrounded by the sea, amidst tropical vegetation. It consists of a series of big shells, ogival pavilions ranging between 9 and 24 meters high, asymmetrically articulated along a main axis.
The central structure links up the various groups of pavilions by organizing the routes and housing the heaviest structures.
The Center, rather than a museum, is very much like a “promenade,”unfolding outdoors as well as indoors. The realization of the cone-shaped structures confirms the close connection between the memory of the Kanak culture and the adoption of modern techniques.
The-curved walls consist of three different diaphragms allowing adequate natural illumination: a system o movable curtains, a wall of laminated wood and an additional bamboo wall filter the light and the sounds of the tropical forest by letting nature “sing.” The big shells trapping the wind obtain natural ventilation from the environment by channeling air in the lower part of the construction and by blowing warm air outwards through a convection system. The performances of the shells have been also studied with every kinds of wind in order to analyze the natural ventilation in each climatic conditions.

High Rised Offices and Residences ,Sydney.
To celebrate the Olympic Games in Sydney in the year 2000 the Australian corporation, Lend Lease Development, initiated and commissioned the design and construction of a commercial tower and a residential building.
The challenge was of a social order: to build a people-friendly environment where residents and employees would cross paths unobtrusively.
The project is comprised of two buildings linked by a glass-covered square which creates an urban microcosm.
The office tower is 200 meters high, rises 44 levels, and encompasses 49,000 square meters. The residential building has 17 levels and faces Sydney’s Botanical Gardens.
A lot of models and computer simulations were made in order to analyze the influence of the wind on the structure, in particular on the tower’s main façade.
The tower was designed to allow integration between the levels, which was achieved in part by the inclusion of winter gardens and terraces.
The design has a built-in ethereal quality making it less imposing on its surroundings. It was important to give it a delicate, free shape, as captured in the shell-like slope of the main facades. The fritted glass “skin” of the building regulates the sun’s rays and wall temperatures, while taking on a homogenous cream-white, ghostly pallor. This glass skin extends beyond the building volume, dissolving its edges, and accentuating the building’s overall lightness.
This exceptionally shaped skyscraper meets the project’s main dictate: to construct a building that, while immense, remains human and hospitable.

3.3 The Space
One of the new concept of the Piano’s space is the sphere.
From when he was young, this kind of form influenced him and he developed this concept step by step, in different kind of materials and constructive systems.
Following this way he arrive to produce his famous “glass-bubbles”, in particular the Lingotto’s bubble,a conference room sited on the top of the building, and the Genoa’s “biosphere”, an exposition area of the Genoese’s ferns. In both the projects a particular attention was given to the internal climate, studying the aeration and the sun influence.
In the summer a natural ventilation will be able to digest the heat by the openings power-operated from an hydraulic principle.
The maintenance of the temperature during the winter period will be guaranteed from one heat pump in a position to exchanging the heat of the water of the sea for feeding perimetrical radiators, placed in correspondence of the expositive level.
The protection from the direct radiation for the ambient inside is guaranteed from particular curtains,to imitation of the nautical sails.


[1] “Renzo Piano Building Workshop . Complete Works. Vol 1”;Peter Buchanan; Phaidon press; 1993
[2] “Renzo Piano Building Workshop . Complete Works. Vol 2”;Peter Buchanan; Phaidon press; 1995
[3] “Renzo Piano Building Workshop . Complete Works. Vol 3”;Peter Buchanan; Phaidon press; 1997
[4] “Renzo Piano, Buildings and Projects 1971-1989”; Renzo Piano; Rizzoli;1989
[5] “Renzo Piano. Progetti e architetture 1964-1983”; Massimo Dini; Electa;1983
[6] “Renzo Piano. Progetti e architetture 1984-1986”; Massimo Dini; Electa;1986
[7] “Dialoghi di cantiere”; Renzo Piano; Laterza;1986
[8] GA Architect .14. Renzo Piano Building Workshop

[Abb.01] Renzo Piano
[Abb.02] Menyl Collection, exterior
[Abb.03] Menyl Collection, interior
[Abb.04] Cy Twombly Pavilion, exterior
[Abb.05] Cy Twombly Pavilion, interior
[Abb.06] Cy Twombly Pavilion, scheme
[Abb.07] Lowara Offices, interior
[Abb.08] Lowara Offices, scheme
[Abb.09] Thompson Optronic Factory, interior
[Abb.10] Thompson Optronic Factory, schema
[Abb.11] Workshop Vesina, section
[Abb.12] Workshop Vesina, details
[Abb.13] Workshop Vesina, interior
[Abb.14] Numea, scheme
[Abb.15] Numea
[Abb.16] High Rised, Sydney, scheme
[Abb.17] High Rised, Sydney, scheme_2
[Abb.18] Bubble Lingotto, Turin
[Abb.19] Bubble Lingotto, Turin, 2
[Abb.20] Biosphera_Genoa
[Abb.21] Biosphera_Genoa, 2
[Abb.22] Bubble,detail