Lightweight Concrete – Variety and Elegance

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Lightweight concrete – variety and elegance www.liapor.com

Modern architecture in Switzerland Monolithic with

For Patrick Gartmann, concrete has a special fascination. The Swiss engineer and architect‘s dedication and creativity in the handling of this material becomes clear from a visit to his own house near Chur in the canton of Graubünden. The monolithic design of the building conveys an impressive sense of modern aesthetics. To make this “poured-in-place” concept a reality, Patrick Gartmann chose Liapor‘s innovative insulating concrete which is manufactured by combining the lightweight aggregates Liapor expanded clay and Liaver expanded glass.

“Living rough”: The untreated construction materials used in the building give a primitive, unadorned impression.

2 liapor news Lightweight concrete Project

Patrick he Böschenstraße, a street in Gartmann‘s Chur, passes alongside the house sets new T standards thanks eastern foot of the Hochwang to the use of mountain (2,532 m) and offers a Liapor insulating fascinating panorama. The view concrete. plummets from on high down to the Rhine valley below: to the left, the city of Chur and, to the right, on the opposite bank of the river, the slopes of Mount Calanda (2,697 m). This is the site for the house where Patrick Gartmann, of the engineering firm Conzett, Bronzini, Gartmann AG, Chur, now lives. For his residence, the architect designed a three-storey dwelling conceived as a monolithic concrete construction which stands between two similar buildings on the slopes of the Hochwang. Monolithic with Liapor insulating concrete

A tour of the construction construction materials used in the building give a primitive, When you step off the Böschen- unadorned impression. This is straße and into the courtyard, why the living room with its the first thing you find is a flat- ground though unpolished roofed building similar to a concrete floor which incor- bungalow. This third, topmost porates an underfloor heating floor is the entry point and system feels unusual. Walking provides access to the other over the raw concrete, it is easy storeys. However, it also accom- to feel its deliberate roughness. modates the living room and The walls, too, are made of adjacent bedroom which is concrete and were again left separated from the stylish untreated after the removal of bathroom by an opaque, sand- the formwork – just like the blasted sliding glass partition. ceiling which simultaneously acts The living room contains a as the flat roof. Here, Liapor‘s number of special features: The insulating concrete with its North/South axis and the radiators have a natural steel two large windows that face one above-average thermal interesting play of light it lets in finish and are neither painted another on the eastern and insulation properties plays a causes the concrete to glow in a nor enameled. Another western sides of the room particularly important role. range of different shades. The interesting detail: On several provide interesting inward and middle floor houses a large occasions, Patrick Gartmann has outward views. The fact that Above the EXPO workshop with three amply-sized worked with the Swiss urban Patrick Gartmann feels at home windows and an incomparable architect Peter Zumthor and, as a on a building site has contrib- After the visitor has passed view over Chur and Mount consequence, was involved in the uted much to the design of the through the entrance area, a Calanda. This storey again planning and realization of the house. The visitor soon discovers staircase branches off to the two reflects the architect‘s desire to Swiss Pavilion at the EXPO 2000 where the charm of `living lower floors. This is precisely achieve something pure, in Hanover. From this greatly rough‘ lies. The untreated aligned with the building‘s untainted and natural. Thus, the admired, harmonious Swiss 

liapor news Lightweight concrete 3   construction in the form of a spatial structure measuring 50 by 60 meters of overlaid Scots and Douglas pine, Patrick Gartmann secured a small number of wooden planks which he then converted to create a wooden floor. Descending the stairs once again, the visitor finds the generously-sized kitchen/living room which measures approximately 5.5 x 13.5 meters. The openings on the western side

Architect profile

Patrick Gartmann This modern such as the Liapor insulating building offers • Born in 1968, Engineering concrete mentioned above impressive internal diploma (FH) and architecture and external provide not only the required diploma (FH/STV). views. • Studied as a structural stability but also the desired engineer at the Chur Academy insulating properties. There are of Technology and Economics (HTW). Graduated 1994. no vapor barriers, insulation • Studied architecture at Chur layers or plaster. Consequently, HTW. Graduated 1998. the construction phase consisted • 1998 – 2000 Assistant to simply of removing the formwork Valerio Olgiati at Zurich‘s Technical University (ETH). and drying the resulting struc- Liapor expanded clay • Since 2001 Lecturer in IT and ture. This monolithic construction and Liaver expanded glass Construction Principles at method not only reduces the Chur HTW. effort and time required for Liapor‘s innovative insulating Alongside many surface con- building. The concrete surfaces concrete (patent applied for) structions, the engineering firm that are produced are so uniform represents an intelligent mixture Conzett, Bronzini, Gartmann and finely structured that no of cement and the lightweight produces its identically named AG, Chur, has constructed more than 20 bridges in the canton additional treatment or finishing aggregates Liapor expanded clay expanded glass granulates using of Graubünden, including the is required. The aesthetic impact and Liaver expanded glass. Both a patented procedure with high- award-winning Pùnt da Suran- they make has a contemporary expanded clay and expanded quality recycled glass as the raw suns Viamala. feel in all respects. In Gartmann‘s glass are manufactured using a material. Liaver is a mineral- Conzett, Bronzini, Gartmann AG creation, the walls and ceilings similar granulation and burning based, fiber-free, ecological Dipl.-Ingenieure ETH/FH/SIA, are constructed from concrete or process. After careful prepara- material with a uniform, fine- Bahnhofstraße 3, 7000 Chur www.cbg-ing.ch Liapor insulating concrete de- tion, the raw clay used for Liapor pored structure and a broadly pending on the static require- is fired in a rotary oven at a closed surface. Both Liapor ments and desired insulation temperature of approximately expanded clay and Liaver consist exclusively of sliding glass values. Liapor insulating concrete 1,200 °C. This operation burns expanded glass are characterized doors. These provide access to is the ideal material for modern, off the evenly and finely by low unit weights which form the 100 m2 veranda and a garden monolithic constructions. Thanks distributed organic components the basis for their outstanding measuring 350 m2. to its above-average thermal in the clay. The clay spheres ex- thermal insulation properties. insulating properties, it ensures pand, resulting in the air-ent- Consequently, Liapor insulating Monolithic construction long-term energy savings even rained ceramic expanded clay. concrete can be manufactured at when used in monolithic construc- Liapor expanded clay possesses a a low specific gravity of less than Monolithic constructions are tions. The thermal insulation somewhat rough, closed surface 1,000 kg/m3. Liapor‘s optimum characterized by the fact that the values can be modified slightly coupled with a uniform, fine particle strength and the high walls and ceilings consist of only by adapting the concrete mix as internal pore structure. Liaver, a compressive strength of the a single layer. Concrete products required. member of the Liapor Group, expanded glass granulates pro-

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Outstanding The architectural journal “Hochparterre”, the Swiss television program “Kulturplatz” (broadcast by DRS) and Zurich‘s famous Design Museum combine to form a highly-respected Swiss committee that awards prizes every year for outstanding achievements in the field of architecture, landscape design and design. The concrete walls Patrick Garmann‘s house were left unadorned in Chur was awarded the after the removal of architectural award “Silberner the formwork. Hase für Bestleistung Architektur 2004” for the overall creation consisting of the underlying architectural idea and the innovative Liapor insulating concrete used to realize it.

vide the perfect basis for a wide strength and thermal insulation. site on a just-in-time basis precise- concrete. The second design range of applications in the con- During the design and construc- ly as specified. The Liapor insu- element featuring in Gartmann‘s struction sector: from lightweight tion of his house, Patrick Gart- lating concrete used for the structure is glass which is aggregates for lightweight mann benefited from the coop- construction possesses a lambda perfectly complemented by the concrete, mortar and plaster eration of Daniel Meyer and value of 0.32 W/(mK) thus exposed concrete. The structure products through to formwork. Walter Capatt. Daniel Meyer, making it possible to achieve contains approximately 90 m2 of Managing Director of Liapor a heat transmission coefficient glass in the form of windows, Special formula Switzerland, launched a series of of 0.53 W/(m2K). sliding windows and sliding laboratory tests designed to doors. And one more special The air inclusions that character- identify the ideal insulating Concrete and glass feature: the glass/concrete joint ize Liapor expanded clay and concrete. The preferred cast is realized using an invisible Liaver expanded glass ensure an concrete prototypes were then Patrick Gartmann‘s modern, mono- technique which means that excellent level of thermal subjected to stringent EMPA lithic house is not impressive there is no need for wooden insulation. Thermal bridges are tests. Walter Capatt, technical because of its architectural design frames. ● particularly rare in monolithic director of Calanda-Beton AG alone. It sets new standards constructions. The special formu- in Chur, was responsible for en- thanks to the use of Liapor insu- Further information: la used for Liapor insulating suring that the ratios resulting lating concrete. The beautiful, Liapor Schweiz Vertriebs GmbH concrete makes it possible to from the laboratory work were even surface of Liapor insulating Phone ++41(0)62/206 91-20 adapt the structure that is to be perfectly replicated on site. The concrete meets exacting aesthetic [email protected] created to the specific require- Calanda concrete works deliv- demands and points the way www.liapor.ch ments in terms of compressive ered the concrete mixes to the toward the use of exposed

liapor news Lightweight concrete 5 Frankfurt/Oder district and local court Liapor lightweight concrete for Brandenburg‘s court house

The new district and local court in Frankfurt/Oder has a monolithic design achieved using Liapor LB 15 lightweight concrete which boasts the qualities required of exposed concrete. The concreting activities were completed in September 2004 and the legal departments‘ employees are now in full possession of their new building.

he newly constructed district A rectangular annex at the rear crucial role, the wall could not a pilot project during which a Tand local court in Frankfurt/ of the complex reaches through have any inclusions or uneven number of institutes provided Oder forms part of a building to the atrium. The compact areas.” The choice of material scientific support. The employed program undertaken by the State overall design is emphasized by was also prompted by the cus- lightweight concrete consisted of of Brandenburg to accommodate the monolithic appearance of the tomer‘s functional requirements. Liapor expanded clay spheres its courtrooms and District new court buildings. Only by For example, the way the facade with a grain size of 2 to 8 milli- Attorney‘s office. The Berlin- using lightweight concrete was it has been designed using light- meters, Liapor K sand of 0 to based architects Bumiller & possible to satisfy the architec- weight concrete also meets the 2 millimeters, fly ash, additives Junkers decided to realize all the tural demands placed on the requirement for flexible room and water. This formula resulted elements of the facade using facade. Lightweight concrete sizes. As the architect explains, in a low thermal conductance Liapor lightweight concrete. gives the buildings a sculptural “the facade had to be equipped level of λ = 0.45 W/(mK) coupled quality while simultaneously pro- with numerous connection points with a bulk density of only Lightweight concrete chosen viding the necessary thermal insu- for the partitions. “Apart from 1.2 kg/dm3. Thanks to this special for design reasons lation qualities. “The sculpted an aesthetically less pleasing grid composition, Liapor lightweight design of the walls was only facade, the only option was to concrete is able to achieve The new complex of buildings on possible by using a single-skin construct a lightweight concrete strength class 15 despite its low the Müllroser Chaussee is enclosed construction in exposed concrete facade.” A total of approximately weight. This means that it is just in a square space which results in quality,” says Georg Bumiller to 3,500 cubic meters of densely as strong as normal concrete. a rectangular internal courtyard. explain the architectural concept. textured Liapor LB 15 lightweight “We could never have achieved concrete was used for the facade Exposed concrete quality Construction details this compact, monolithic impres- of the court building which • Client: Frankfurt/Oder state sion by employing a multilayered measures between 60 and 90 The Liapor lightweight concrete planning department cladding technique. Since the centimeters in thickness. This was supplied by the company • Design: design of the surface plays a external wall was constructed as Lichtner Beton GmbH & Co. Bumiller & Junkers Architekten, Berlin www.bumillerarchitekten.de • Planning of the substructure: Pichler Ingenieur, Berlin • Gross volume: 20,000 cubic meters • Usable surface area: 6,600 square meters • Building costs: 19.6 million euros • Construction period: two years, nine months • Concrete supplier: Lichtner Beton, Berlin

The multi-level foyer (left), galleries providing access and waiting areas (right) .

6 liapor news Lightweight concrete Project

All the facade elements of the Liapor lightweight Frankfurt/Oder district and local court are made from Liapor lightweight concrete for Brandenburg‘s concrete. court house

Betriebs KG Berlin from its site in Frankfurt/Oder. “This was the first time we had worked for use as exposed concrete for together with Liapor and we are the construction of the Frankfurt/ very happy with the end result,” Oder district and local court. “At explains Thomas Crimmann from the same time, a construction Lichtner Beton. “Using Liapor as using Liapor lightweight concrete an additive proved to be the best was attractive because it is such way of meeting the exacting a cost-effective material,” says requirements concerning the Georg Bumiller. uniformity of the material.” Stationary tower cranes A rectangular construction delivered the material directly to the formwork structure via This new five-floor building movable containers and flexible constructed at the edge of the hoses. This was then compacted city of Frankfurt/Oder is located by means of needle vibrators. close to a group of former Thanks to its excellent flowability barracks. The layout of the The design makes a and low level of shrinkage, Frankfurt/Oder district and local compact, monolithic impression. Liapor lightweight concrete can court radiates outwards in all be compacted quickly and forms directions. This has made it a uniform surface structure with possible to delineate clearly no blisters or rough areas. This between the judiciary and the symbol for the city and the waiting space. In the newly was the reason for choosing it executive and create a potent surrounding countryside. The constructed district and local rectangular construction whose court in Frankfurt/Oder, Liapor sides measure approximately lightweight concrete has been 60 meters in length has two able to prove its versatility, its office wings and a set of public aesthetic potential and its many chambers. After crossing a small construction-related capabilities. inside courtyard, visitors reach the Liapor lightweight concrete can multi-level foyer that provides be supplied in individually access to the chambers which are tailored settled and bulk also arranged on a number of densities as well as with a variety different storeys: on the one side, of grain sizes. This gives a public space within the building architects great freedom during and, on the other, a link providing their design work. ● access to the courtrooms. The courts of criminal justice occupy Further information: the two lower levels of public chambers while civil cases are Liapor GmbH & Co. KG heard in the smaller courtrooms Phone ++49(0) 95 45/448-0 [email protected] on the upper floors. The galleries www.liapor.com which converge on the central hall serve provide both access and

liapor news Lightweight concrete 7 The building was intended to be unadorned and natural, conceived as a concrete foundling in the forest. That is how architect Rüdiger Trager designed his house which he had constructed in a monolithic design from

Liapor insulating concrete. With its clean, pure lines, the house fits like an inhabited cave into the slopes that border the city of Heidelberg. The unfinished feeling of the construction with its rough concrete surfaces and the limited use of other natural materials such as oak and glass emphasize the building‘s striking, natural look.

A monolithic construction using Liapor insulating concrete Total aesthetics

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Northern view Total aesthetics in Heidelberg

hen designing the house W in which he wished to live, Rüdiger Trager was inspired by the building land itself which is located on a steep, wooded slope in a long, narrow valley in Heidelberg. Another factor was his love for concrete as a building material. As a result, Rüdiger Trager, a partner in the Heidel- Western view berg company ap88 Architekten, The “inhabited found out everything he could cave” burrows about monolithic construction deep into the hillside. techniques and Liapor as a build- From the kitchen, it is possible to simple, natural design. Here, ing material. It did not take long access all the private rooms in the Rüdiger Trager chose smoothed for him to decide to use a mono- ground and first floor along a screed except in the private lithic approach to the design of narrow corridor. These private rooms where oak boards are his own home. spaces follow one another like a used. All the fixed installations string of pearls. One of these is are manufactured from MDF Constructed on the slope the amply-sized ground floor liv- wood panels. “As a result, the de- ing area, a polygon with walls sign and crafting have an imme- The three-floor house construct- that meet at oblique angles and diate, authentic impact,” explains ed from Liapor insulating con- a sloping ceiling whose height of Rüdiger Trager who decided to crete is set back from the double 5.5 meters gives the visitor the employ only the three natural garage and burrows far into the feeling of being in a cathedral. It building materials: concrete, slope. A steep outside stairway is the diagonal that determines wood and glass. This natural im- leads from the garages to the the feeling of space since the pression is further supported by Deliberate lower floor which is entered rooms are accessed from the cor- the vegetation which is typical of simplicity: through an imposing oak door ner of this area. As a result, most the building‘s location at the untreated and gives access to the office of the windows are located in edge of the forest. The land, lightweight concrete space. A concrete stairway rises the opposite corner and offer a which covers approximately  surfaces. to the ground floor with its cen- view of the luxuriant natural en- trally located kitchen/living room. vironment outside. The staircase This room, which the Trager fam- leading up from the living area ily planned to be at the center of leads to the top floor which ac- their house, combines the func- commodates the bedrooms, chil- tions of a passage way and living dren‘s rooms and bathroom. room. It is here that the family meets to talk and enjoy one an- Natural building materials other‘s company – in particular, the bench made out of a single The client and the architect chose piece of oak in the corner of the to use simple, shuttered concrete room is a popular meeting place. for the walls, ceilings and stair- Here, the large panoramic win- cases as well as for the gable roof dow provides a wonderful view with its mixture of inclines. The of the surrounding countryside. floors are also characterized by a

liapor news Lightweight concrete 9

  760 m2, was planted with large trees, shrubs and fruit trees. Grav- el is used for the paths and relaxa- tion areas. The owner decided to use no ornamental plants since he wants nature to reclaim the land.

Monolithic construction

To ensure that all the external walls and roof coverings complied with the requirements of the German energy savings regulations and were manufactured from locally sourced concrete, all the external elements were cast in one piece to a thickness of fifty centimeters using Liapor insulating concrete. All the internal walls and ceilings are made of normal concrete. The surfaces of the various elements were either left

Architect profile

Ground floor

Rüdiger Trager

Born in 1969 Engineering graduate Independent architect and Straight lines, untrammeled member of the German unfinished or oiled. The Rüdiger Trager found a skilled aesthetics: the house belonging Architects‘ Association (BDA) monolithic construction is partner who, in cooperation with to architect Rüdiger Trager in Studied architecture at impressive not only due to its the local concrete supplier Heidelberg Kaiserslautern Technical Academy striking visual impact, rough Kurpfalzbeton GmbH, was able to Graduated 1994. surface structure and outstanding develop the perfect mix for the Liapor expanded clay Since 1997: ap88 Partnership thermal insulation properties task. First of all, sample panels of architects and member of thanks to the use of lightweight were manufactured, followed by Liapor insulating concrete is the the BDA 2002 concrete, but also due to the a trial wall using a number of ideal building material for His work focuses on multistory considerable reduction in different formwork variants. As monolithic constructions since, in residential and commercial construction time resulting from an architect, Rüdiger Trager most cases, it meets all the buildings and he regularly this technique. decided for a simple and no requirements relating to bearing takes part in national and international competitions at The Trager family was able to longer totally new steel strength, safety, resistance to heat which he is able to attract new move into their new house in shuttering system which met the and damp as well as fire resistance customers and put his own November 2006, just two months needs of the divisions provided and acoustic insulation much achievements and innovative after the carcass work had been for by the floor plan. As a result, better than conventional prowess to the test completed. However, a certain the rough surfaces of the walls concrete. This is due to the use of ap88 Architektenpartnerschaft amount of preliminary work was seem to be bursting with vitality Liapor expanded clay spheres as a Bellm, Löffel, Lubs, Trager required in order to identify the despite the simplicity of the lightweight aggregate together Freie Architekten BDA right formula for the concrete employed material. The marks left with a formula versatile enough Sickingenstr. 39 69126 Heidelberg used in the external walls and the by the shuttering, clamp marks, to cope with any construction www.ap88.de ceiling. In Adrian Wolf, sales nail holes and scratches were all a project. Ceramic Liapor expanded adviser at Liapor GmbH & Co. KG, part of the architect‘s vision. clay possesses a somewhat rough,

10 liapor news Lightweight concrete Project

The structure shows the past summer. “The internal just what goes into ambience is considerably better Liapor lightweight concrete: top-quality than with normal concrete and expanded clay for offers excellent protection optimum thermal against heat in the summer,” says insulation. the building‘s owner whose thermometer never climbs above 23 °C in the living areas even on hot summer days. The house possesses geothermal heating. The Trager building in Heidelberg is a further illustration of the versatility of Liapor lightweight concrete and the ease with which it can reconcile designers‘ ambitions with the applicable legislation, building regulations and technologies. It is the natural look of Liapor insulating concrete that opens up new outlooks and creative alternatives in the field of architectural design. Thanks to its beautiful, even surface, Liapor closed surface coupled with a lambda value of 0.36 W/(mK) exacting, it was possible to insulating concrete is ideally uniform, fine internal pore thus making it possible to reduce these times to only three suited for exposed concrete structure. Though low-weight, achieve a heat transmission to four days. Shortly after the applications in striking residential Liapor provides optimum particle coefficient of 0.6 W/(m2K) in the removal of the formwork, the buildings, as architect Rüdiger strength and therefore walls. The roof was also concrete surface on the outside Trager has shown in the design constitutes an excellent building constructed using lightweight of the building was treated with of his own house. Back to nature material. Liapor expanded clay is concrete. However, concrete of a water-repellent agent to pre- and humanity‘s roots is the characterized by low unit weights strength class LC 12/13 with a vent any moisture penetration. owner‘s credo – and it is precisely which form the basis for its bulk density of 1200 kg/m3 was All the internal walls were left this that he has achieved with his outstanding thermal insulation used for this application. The with their natural appearance “inhabited cave” on the hilly properties. The lightweight heat transmission coefficient of unchanged. “The walls in our slopes near Heidelberg. ● concrete made of Liapor the roof is also 0.6 W/(m2K). house should radiate with their expanded clay and CEM III pure beauty. There are no images cement used for the external A versatile visual impact to disturb the visual impression, skeleton of the Trager family the versatility of the concrete Further information: house belongs to strength class The composition of the concrete makes its own impact,” explains LC8/9 and possesses a bulk density would normally have meant Rüdiger Trager as he describes of 1000 kg/m3. Thanks to its low that extensive form removal the aesthetics of the striking con- Liapor GmbH & Co. KG, weight, this lightweight concrete times were required after crete surfaces. The client and his Phone ++49(0) 95 45/448-0 [email protected] is able to achieve extremely good casting. However, because the family were also able to experi- www.liapor.com insulating values. Liapor client‘s requirements in terms of ence the climatic benefits of insulating concrete possesses a the concrete surface were not Liapor insulating concrete during

liapor news Lightweight concrete 11 There is nothing unusual about an architect designing his own house. However, if the construction also has a scientific use then the building becomes something special. Like the house which Professor Mike Schlaich designed as a monolithic construction made from superlightweight concrete and in which he now lives. The Managing Director of the renowned Monolithic construction with

engineering firm Schlaich, Bergermann and Partners has made his family home in the east of Berlin available to science almost as if it were a test center. Together with his team and in close cooperation with Liapor, Schlaich, working at Berlin‘s Technical University, has developed a superlightweight concrete which exhibits outstanding thermal insulating properties coupled with a dry unit weight of less than 800 kg/m3 thanks to the use of Liapor expanded clay as a lightweight aggregate.

12 liapor news Lightweight concrete Material developed in the university lab: The Schlaich building. Project

Monolithic A residential building in Berlin‘s Prenzlauer Berg district construction with superlightweight concrete

n recent years, architects have I rediscovered the art of using lightweight concrete as an exposed material. As a result, a number of monolithic exposed concrete constructions made of lightweight concrete with its excellent thermal insulation properties have been built in Switzerland and Germany. On the one hand, Ground floor exposed concrete is fascinating due to its exceptional architectural qualities. On the other, monolithic, single-skin concrete substruc- tures are particularly long-lived. The fact that there is no plastering or cladding work means that costs can be reduced and materials are easier to recycle. “Our house was inspired, among other sources, by the Gartmann building in Switzer- land which is also constructed ed clay and air-entraining agents, better than conventional con- using a monolithic design with ex- perfectly satisfied the defined ob- crete. Liapor expanded clay pos- posed concrete walls. However, jectives. The fact that this innova- sesses a somewhat rough, closed my idea was to develop an even tive superlightweight concrete is surface coupled with a uniform, more lightweight concrete with a also ideally suited to practical use fine internal pore structure lower bulk density. As a result, the is convincingly demonstrated by Though low-weight, Liapor pro- For a number of principles underpinning our house the Schlaich family house whose vides optimum particle strength reasons, exposed were initially developed in the external walls are constructed and therefore constitutes an ex- concrete is again one of today‘s laboratory,”explains Mike Schlaich, from this material. cellent building material. The cho-  trends. head of the department responsible for solid construction at Berlin Liapor as a lightweight Technical University‘s Construction additive Engineering Institute. During the summer of 2006, Mike Schlaich The superlight concrete, in which worked together with his col- Liapor expanded clay is used as a leagues at Berlin‘s Technical Uni- lightweight aggregate, is the versity and with Liapor‘s Maik ideal building material for mono- Dostmann to develop a formula lithic constructions since, along- for a particularly lightweight con- side its outstanding thermal insu- crete with outstanding thermal in- lating properties, it usually meets sulating properties and a dry unit all the requirements relating to weight of less than 800 kg/m3. The bearing strength, resistance to resulting formula, which consisted heat and damp as well as fire re- of water, cement, Liapor expand- sistance and acoustic insulation

liapor news Lightweight concrete 13

  sen materials were Liapor 1-4 round granules and Liapor F 2.9 A monolithic construction using together with Liapor‘s sand superlightweight product “Liapor L Sand 0/2” concrete: At a dry which further enhances the con- unit weight of just 3 crete‘s thermal properties. Ce- 760 kg/m , the coefficient of thermal trans- ment of CEM III-A 32.5 quality, mission calculated water and air-entraining agents for the walls is were also used in the superligh- 0.34 W/(m2K). weight concrete formula. Thanks to this combination, it was possible to limit the dry unit weight 0.18 W/(mK) and the resulting co- pacted using conventional vibra- signed house in the Prenzlauer Berg of the monolithic exposed con- efficient of thermal transmission tors. A period of one week was district, the diplomatic center of the crete walls to just 760 kg/m3. As for the walls is 0.34 W/(m2K). required to remove the form- former GDR. The building was de- a result, the superlightweight work. Nevertheless, this trial use signed by the architects Amanda concrete is able to achieve excel- Glass fiber rod reinforcement of superlightweight concrete re- Schlaich and Clemens Bonnen. On lent thermal insulation values. sulted in a significant amount of established wooded land measuring The measured lambda value is This superlightweight concrete cavitation. Fortunately, a little approximately 1,500 square meters, achieves a level of strength com- touching up with a mortar pro- the modern building with its pure parable to that of LC8/9 light- duced from CEM III-A and ex- rectangular forms (9.75 x 13.42 me- Architect profile weight concrete. One of the key panded glass granules coupled ters) blends perfectly with its envi- interests of the project lay in the with some facing work performed ronment. The building‘s eastern and need to adapt the constructional by the owners themselves and the western sides consist entirely of ex- and physical details to the proper- application of a water repellent posed concrete walls, while the ties of the material and explore resulted in an interesting and possibilities not usually consid- stimulating but also smooth con- ered when steel-reinforced concrete surface achieved with com- crete is used. To reduce the other- paratively little work. Inside the wise unavoidable formation of building, the exposed concrete cracks due to shrinkage, glass walls were left with their natural fiber rods were used as reinforce- appearance unchanged. Professor Mike Schlaich ment. This made it possible to (doctor of technology and both solve the problem of corro- A modern architecturally science) sion and avoid thermal bridges. designed house 1960 born in Cleveland, Simple concrete shuttering with- Ohio, USA out any partitioning was used for In the summer of 2007, after a • Academic history: 1979 – 81 Studied engineering at Stutt- the formwork of this exposed construction period lasting almost gart University to primary level concrete building. The light- exactly one year, the Schlaich fam- 1981– 85 Swiss Technical Acad- weight concrete was transported ily was able to take up residence emy (ETH) Zürich (ETH/SIA certi- to the site in buckets and com- in its modern, architecturally de- fied engineer), In-depth study of building construction and materials technology with pro- fessors Menn, Dubas and Rössli 1985 – 89 Assistant to Professor Anderheggen in the Engineer- ing IT department (co-lecturer: Professor Thürlimann) • Professional experience: 1990 – 93 Engineer at FHECOR, consulting engineer in Madrid, Spain 1993 Engineer at Schlaich, Bergermann and partners since 1999 Partner since 2005 Test engineer for building statics specializing in solid construction • Teaching responsibilities: 2000 – 2004 Teaching responsibilities at Stuttgart University: “Building with ropes” since 2004 Professor of solid construction at Berlin Techni- cal University‘s Construction Engineering Institute

14 liapor news Lightweight concrete Project

A modern architecturally designed house: Exposed concrete is Schlaich has handed over most of the dominant design the architectural responsibilities element. to his wife, he himself has contin- ued to concentrate on structural polished to create an exclusive, el- concerns. “Our experience so far egant terrazzo finish. Oak floor- has shown that superlightweight ing was laid in the children‘s bed- concrete makes it possible to pro- rooms and the other room on the duce exposed concrete structures second of the upper floors. The with good thermal insulation house possesses geothermal heat- properties and has the potential ing. In addition, a mechanical ven- to play a far from negligible role tilation system ensures that cool in the construction industry of the air is continuously supplied to the future.” ● house while the stale air is removed. Further information: northern and southern facades first floor which houses two chil- are characterized by a post-and- dren‘s bedrooms and bathrooms. Further annexes planned Architects: Clemens Bonnen, Amanda Schlaich mullion construction, striking The second floor contains the bed- Construction engineers: glazed areas and anodized alumi- rooms, workshop and bathroom However, building work at the Mike Schlaich, Lars Werner num panels and a narrow exposed as well as an additional workshop Schlaich family house is not yet Mix/formula: Jointly deve- concrete wall. In total, the house which also serves as a guestroom. complete. Two wooden terraces – loped by the materials and materials testing and solid provides a living space of approxi- All the bathroom installations and one on the northern and one on construction departments at mately 190 square meters distrib- the lift are located on the side of the southern side – and two small Berlin‘s Technical University uted across three floors. Due to the house that has been finished annexes to the South (a garden Construction company: the high groundwater level, the with exposed concrete walls. The building and a garage space) are Kasimir Bau, Berlin Concrete plant: Lichtner cellar was constructed using wa- remaining rooms possess generous planned in the future to finish off Beton, Berlin terproof concrete. The ground glazed facades manufactured this striking residence. “Since our Glass fiber reinforcement: floor accommodates a spacious from triple-layered safety glass. In house is 20 meters away from the Schöck, Baden-Baden hallway, a kitchen, a large living/ the inside of the house, the own- road, we want to create a dry in- Testing engineer: Hartmut Kalleja, Berlin dining room which opens onto ers, Amanda and Mike Schlaich door courtyard on the southern the first of the upper storeys, to- also placed great emphasis on the side. In contrast, the Northern Liapor specialist consulting: gether with a guest bathroom and use of natural materials. The side is intended to be a restful, Liapor GmbH & Co. KG WC. A staircase made from con- floors on the ground floor and in natural area,” says Amanda Schla- Phone ++49(0) 95 45/448-0 [email protected] crete cast in-situ, which has also the bathrooms are made from ich describing the planned con- www.liapor.com been left unadorned, rises to the poured asphalt which was finely struction activities. While Mike

liapor news Lightweight concrete 15 Gebrüder Meier AG and AquaPura AG company headquarters, Birrhard A Swiss construction jewel

Simplicity and efficiency were the watchwords behind the construction of the new company headquarters and factory site commissioned in Birrhard by the Swiss company Gebrüder Meier AG to celebrate its 100th anniversary. After 14 months of construction work, the result was a striking architectural highlight which combines aesthetics and functionality within an exceptional complex of buildings.

16 liapor news Lightweight concrete Project

or Gebrüder Meier AG 2007 F was a special year. The Swiss civil and highway engineering company not only celebrated its A Swiss 100th anniversary but also commissioned the construction of a new factory site at its premises in Birrhard in Switzerland‘s Aargau. construction The main aim behind the creation of the new company headquarters was to concentrate the various functions in a single location. jewel “We had reached the limits at our old site in Windisch and the type of expansion required for the fu- Eastern view ture was no longer possible,” explains Richard Fischer, Vice Presi- dent of the Gebrüder Meier AG Board of Directors. The old company premises were sold to provide the finance necessary for the 10.5 million CHF new construction Northern view in Birrhard where the company‘s management had identified the necessary potential for growth.

Functional aesthetics

The owners‘ wishes for the new Western view company headquarters were very clear. The building that was to be as well as for a versatile office inspired by three interrelated key Both the inside and outside of the new erected was to serve as a work- space. With this new company elements. The wall which encloses company headquarters shop, vehicle bay, warehouse and headquarters, Gebrüder Meier AG three sides of the site forms a dis- impress through their office complex simultaneously and its subsidiary AquaPura AG tinct, massive base for the com- functionality and and combine all the company‘s were able to offer their customers plex, says architect Manuel Alber- aesthetics. premises and departments. The an even more extensive range of ati to explain the structure of the resulting synergisms have given services in the fields of highway building. The warehouse and rise to a new, creative working and civil engineering. This is be- workshops, reception and rest approach in spacious premises. cause by concentrating their re- areas as well as the main entrance  “Our guidelines to the architects sources at a single site, the com- consisted of three Es,” says panies are now able to perfectly Fischer. “Easy – extendable – elec- harmonize their solutions for trifying. We wanted to implement complex construction projects. simple, efficient workflows in our office and factory activities. At Three characteristic the same time, we wanted the key elements new location to have an extendable, forward-looking architectural With their spectacular design, the design. An electrifying appear- architects were able to integrate ance for a building characterized the new company premises per- by its quality features was also im- fectly into Birrhard‘s residential portant to us.” On the basis of and industrial environment. This these instructions, Daniel Kündig was no easy task given the varied and Manuel Alberati from the nature of the immediate sur- Zürich-based firm of architects roundings which include a tennis UC’NA created an impressive build- center, a wine merchant and a ing design which met the require- residential district. “The form ments for a functional factory site of the new company premises is

liapor news Lightweight concrete 17 The over- ing agents, stabilizing agents and hanging other additives. To ensure an opti- hollow body mum result, preliminary tests were is one of the highlights of performed in Liapor Switzerland‘s the building. own company laboratories while, at the same time, two reference walls   were constructed in concrete for are integrated and interlinked tory roof forms the complex‘s third sizing the functionality of this test purposes. The facade walls of a within this striking, unbroken key element. Huge Y-shaped pillars striking construction. height of up to 5 meters and a wall element with its serrated bear the weight of the steel con- thickness of 50 centimeters were openings. struction which tapers to form a Liapor‘s structure revealed raised to the required height in a The second key element is the narrow edge strip at both ends single step. After the skeleton struc- elongated structure that extends and thus opens up a view from the High-performance Liapor insulat- ture had been completed, approxi- far beyond the base and accom- offices down onto the storage ing concrete was used to con- mately one centimeter of the exter- modates the office areas with areas below. “In many different struct the ground floor which nal concrete skin was removed their room-height openings. ways, the resulting complex cre- houses office spaces, the work- using high pressure water jets oper- “The office space is structured by ates spaces, tensions and relation- shop and storage areas. The spe- ating at 500 bar to reveal the open the rhythm of the pillars and the ships and enables the civil engi- cially developed mix consisted structure of the expanded clay and two massive centerpieces,” says neering company to optimize its of Liapor 3, 4 – 8 mm and Liaver expanded glass aggregates. This Alberati. The self-supporting fac- workflows,” says Alberarti, empha- 1–4 mm together with air-entrain- structure was then waterproofed.

Architect profile

Prof. Daniel Kündig, Manuel Alberati, certified architect ETH/SIA/BSA certified architect ETH/SIA 1956 born in Zürich 1973 born in Zürich • Academic history: • Academic history: 1978 – 1983 Architectural 1994 – 2001 Architectural studies at Zürich‘s Technical studies at Zürich‘s Technical University University • Professional activities: • Professional activities: Since 2003 UC‘NA Architekten Since 2003 UC‘NA Architekten ETH SIA BSA, with Manuel ETH SIA BSA, with Prof. Daniel Alberati Kündig Since 2001 President of the 2001 – 2003 Self-employed Swiss Engineers’ and architect Architects’ Association SIA 1996 – 2001 Employed at 1984 – 2001 Architekturbüro Kündig . Bickel Architekten Kündig . Bickel Architekten • Teaching activities: • Teaching activities: 2001 – 2006 Assistant to 1986 – 1990 Graduate design Prof. Daniel Kündig, assistant for Prof. Technical College Franz Oswald, ETH Zürich of North West Switzerland Since 2000 Professorship at the Technical College of North-West Switzerland

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From the office spaces, the large glass elements provide provide a view of the storage areas below the self-supporting factory roof.

Further information: Zigzag wall apertures are Another spectacular feature of success right from the start. “This the dominant element of Architects: UC’NA Architekten this new construction is the roof- is not just a building construction. the ground floor. ETH SIA BSA, Zürich ing over the 22.5 meter wide site It is a construction jewel,” pro- Construction engineers: approach. This is suspended by claimed Erich Erne, President of Gerber + Partner, Bauingenieu- re und Planer AG, Windisch six pre-tensioned tie rods located the Board of Directors of the Erne the whole, the harmony in the Construction supervision/ in the top floor from two pre- Group to which Gebrüder Meier interaction of the individual management: Xaver Meyer stressed upstand beams stretching AG has belonged since 2007, at elements and the choice of the AG, Villmergen across the floor of the top floor the inauguration ceremony. Rich- employed materials and colors Planning of sanitary fittings: PGMM Schweiz AG, Winterthur ceiling. The formwork for the ceil- ard Fischer is equally enthusiastic: give the company headquarters a Electrical planning: Herzog ings therefore had to be designed “The results have exceeded our genuine “face” with an unmistak- Kull Group, Schlieren in a way that could support the expectations. Our instructions able profile. It means that the Construction physics: Kopitsis entire weight of the two cover- were followed to the letter and company is optimally equipped Bauphysik AG, Wohlen Planning of retention/drainage: ings, the bearing construction in the costs have been kept within for future tasks. “At present, we Gerber + Partner, Bauingenieure the top floor and the suspender the budgeted framework.” The are witnessing an exciting period und Planer AG, Windisch beams. new building is a unique, exqui- of transition to a future in which Concrete plant: Beton Baden- site design which makes a power- we can push forward with our Brugg, Werk Müllingen Equipped for the future ful aesthetic impact and forcefully developments. Our new head- Liapor specialist consulting: underlines Gebrüder Meier AG quarters with its spacious, func- Liapor Schweiz Vertriebs GmbH Since May 2008, the new building and AquaPura AG‘s claim to be tional areas will naturally help us Phone ++41(0)62/206 91-20 has been the workplace for up to progressive, innovative compa- greatly with our forward-looking [email protected] www.liapor.ch 150 employees – and has been a nies. The aesthetic impression of plans.” ●

liapor news Lightweight concrete 19

20 liapor news Lightweight concrete Project

National Park Center A monolithic white building

Striking, unusual but not intrusive – the Visitor Center at the Swiss National Park is a true symbol of the village of Zernez in the canton of Graubünden. The pure lines of this monolithic construction fit harmoniously into the surroundings. The entire facade and the indoor rooms have been created from Liapor insulating concrete.

he Swiss National Park in Narrow wall Zernez (in the canton of projections slightly T offset the individual Graubünden) is the largest pro- storeys of the three- tected natural area in Switzer- floor building. land. Its alpine landscape and many varieties of animal and plant life are free to develop un- constrained and protected from human activity. At the same time, the National Park is a site for scientific research into flora and fauna. It also acts as an educa- North-South cross-section tional establishment. The information it provides is intended to increase its visitors‘ understanding of nature. This is the task entrust- ed to the Visitor Center, one of the architectural highlights of Zernez. The building‘s monolithic design is the brainchild of re- act the formation of cracks in the Ground floor nowned architect Valerio Olgiati concrete – the individual concrete whose uncluttered conception sections are clearly distinguished. won the competition launched to First of all the corners of the select the best design. building were constructed followed by the center section with Exposed concrete ensures a its window recesses. The achieved memorable impression effect ensures that the result is unmistakably individual and ex- The construction consists of two tremely memorable. imposing intersecting cubes. The The interior of the two white projections on the walls slightly cubes is striking due to its sophis- offset each of the storeys of the ticated room layout. Six halls shar- three-floor building. The symmet- ing the same floor plan are dis- rical panoramic windows set back tributed across the three storeys in the center of each floor are of the National Park Center. The particularly striking. Thanks to the lower floor is dominated by a spa- use of so-called trim-strips around cious reception area from which a the windows which differ in their twin staircase, characterized by its structure and color and counter- interesting perspective, rises to 

liapor news Lightweight concrete 21 First of the upper floors

The National Park Center rises against the backdrop of its surroundings without being intrusive.

  the upper floors. These contain Careful planning and tuned in the laboratory before at the challenges involved in find- the permanent exhibitions. Visi- reliable partners being employed in a series of ing the suitable concrete formula. tors can then descend a second test constructions. “It was clear twin staircase to another room Aldo Duelli from the Olgiati firm that only Liapor expanded clay Outstanding thermal which is intended for temporary of architects explains just what it and Liaver expanded glass could insulation exhibitions. Finally, the tour of is that makes monolithic archi- be considered as lightweight ag- the exhibition rooms ends at the tecture so special: “One particu- gregates due to their particular Adding expanded clay and ex- foot of the same set of stairs lar feature of monolithic con- thermal insulating properties. panded glass to concrete brings a from which it began. structions is the fact that the The task was to develop the cor- number of advantages. The ex- traces of the production process, rect mixture to be used in combi- panded clay spheres are resistant the craftwork, remain visible.“ nation with the carefully pre- to humidity, heat and chemicals. The entire building is made from pared white cement,“ explains They also offer a high level of the same material and character- engineer Daniel Meyer of Liapor compressive strength. Due to the ized by purity and simplicity. At Switzerland when looking back addition of air-entrained pores, Architect profile the same time, the light exposed concrete gives the building an el- egant quality. This type of monolithic technique demands very precise planning. There is hardly any room for improvisation. Con- sequently, Aldo Duelli was full of praise for the trouble-free cooperation between the involved parties: “The Zernez-based concrete plant Sosa Gera SA invest- ed in new factory technology in Valerio Olgiati, order to manufacture the con- certified architect ETH crete used for the building; the 1958 born in Chur local building companies, Foffa & Conrad and Lazzarini AG, con- • Academic history: 1980 – 1986 Studied structed a very precise carcass architecture at Zürich‘s and worked extremely carefully Technical University (ETH) and professionally in accordance • Professional activities: with the specified logistics.“ The 1993 – 1995 Architecture success of this cooperation can company in Los Angeles also be seen from the fact that 1996 Opened a firm of architects in Zürich only two years elapsed between 2008 Company relocated to the start of the work and the Flims Center‘s public inauguration. • Teaching activities: Just as important as the careful 1998 – 2000 Guest lecturer at planning and reliability of the Zürich‘s Technical University partners for the construction of 2002 Guest lecturer at the the Visitor Center was the use of Architectural Association School of Architecture in the ideal concrete formula. London Liapor Switzerland which sup- 2005 Guest lecturer at Cornell plied the lightweight aggregates A staircase opens the University in Ithaca/NY performed extensive tests to de- way to the upper since 2002 Teaching activities rooms which contain velop the mixture used in Zern- at the Universitá della Svizzera the permanent italiana in Mendrisio ez. The composition of the light- exhibitions. weight concrete was first fine-

22 liapor news Lightweight concrete Project

The inside of the building is dominated by the bright exposed concrete and the wide, symmetrical, recessed panoramic windows.

lightweight concrete has a low distinguished depending on the dry unit weight. Its very high insu- weather conditions and angle of lating properties ensure excellent the sun. With its new Visitor Cent- energy efficiency. Only very little er, the Swiss National Park in heating is needed in the winter Zernez possesses an architectural while only minimal indoor cooling highlight that fits effortlessly into is required in the summer. Thanks the impressive mountain scenery to Liapor expanded clay and Liav- of the Engadine. ● er expanded glass, it was also possible to meet the strict requirements concerning the external ap- Further information: pearance of the building. “Both Architect: Valerio Olgiati, materials are completely neutral Certified architect ETH in terms of color. As a result, we www.olgiati.net were able to achieve both the de- Engineering firm: sired insulating qualities and fi- Jon Andrea Könz, 7530 Zernez delity to the color design,“ says Site management: Daniel Meyer. With its white ap- Architectura DC SA and Cas- pearance, the Visitor Center tellani & Bulfoni, Scuol blends perfectly as part of the his- Planning of bathroom torical triad that covers the Na- installations: S. Collenberg & Co., St. Moritz tional Park which also includes the Park‘s administrative head- Electrical planning: quarters in Planta-Wildenberg Kurt Buchegger AG, Pontresina castle and the 150-seat auditori- um in the former Stall castle. Construction physics: mKB, Chur “White emphasizes the identity of the building as an individual ob- Masonry, gravel and concrete: Sosa Gera SA, 7530 Zernez ject and gives it a pure and ab- stract appearance,“ says Duelli. Liapor specialist consulting: Liapor Schweiz Vertriebs GmbH The brightness of the construction Phone ++41(0)62/206 91-20 shines with a constant presence [email protected] without ever being intrusive. Dif- www.liapor.ch ferent shades of color can even be

liapor news Lightweight concrete 23 Dead weight calculation values Bulk density Thresholds of the mean value of Dead weight calculation values class the dry concrete bulk density ρ d Lightweight Reinforced light Concrete wight concrete kg/dm3 kN/m3 1,0 0,80 – 1,00 10,5 11,5 1,2 1,01 – 1,20 12,5 13,5 1,4 1,21 – 1,40 14,5 15,5 1,6 1,41 – 1,60 16,5 17,5 1,8 1,61 – 1,80 18,5 19,5 2,0 1,81 – 2,00 20,5 21,5

Reference values for assigning strength and bulk density classes Strength Minimum required concrete Modulus of elasticity class bulk density [kg/m3] [kN/mm2] Lightweight sand Natural sand Lightweight sand Natural sand LC8/9 1,0 1,2 4,9 7,1 LC12/13 1,1 1,3 5,4 9,0 LC16/18 1,2 1,4 8,2 11,1 LC20/22 1,2 1,4 8,6 11,7 LC25/28 1,3 1,5 10,6 14,2 LC30/33 1,3 1,5 11,1 14,8 LC35/38 1,3 1,6 11,6 17,6 LC40/44 1,4 1,6 14,0 18,2 LC45/50 1,4 1,6 14,5 18,9 LC50/55 1,5 1,7 17,1 22,0 LC55/60 1,5 1,7 17,6 22,6 LC60/66 1,6 1,8 20,5 25,3 LC70/77 1,6 1,9 21,5 30,3 LC80/88 1,7 2,0 25,2 34,9

Compressive 120 Liapor GmbH & Co. KG strength/ 100 Liapor – Werk Pautzfeld bulk density D-91352 Hallerndorf 80

Phone ++49 (0) 95 45/4 48-0 Lightweight concrete 60 Fax ++49 (0) 95 45/4 48-80 with natural sand Lightweight concrete 40 www.liapor.com with lightweight sand High-performance [email protected] lightweight concrete 20 Lightweight concrete with expanded glass Cube compressive strength [MPa] 0 Lias Österreich GesmbH. 0,6 0,8 1,0 1,2 1,4 1,6 1,8 Buildings 3 A-8350 Fehring Dry bulk density [kg/dm ] Phone ++43 (0) 31 55/23 68-0 Fax ++43 (0) 31 55/23 68-20 www.liapor.at [email protected]

Liapor Schweiz Vertriebs GmbH CH-4603 Olten Phone ++41 (0) 62/2 06 91-20 Fax ++41 (0) 62/2 06 91-10 www.liapor.ch [email protected] www.liapor.com