focus on lightweight concrete liaporMagazine for architects, planners and building contractorsnews 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 construc- tion 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 resi- dence, the architect designed a three-storey dwelling conceived as a monolithic concrete construc- tion 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- 4 liapor news Lightweight concrete Project 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