Clear Sign: a Plus for the Future
Text: Tim Westphal
Even after more than 40 years it has lost nothing of its structural quality. Today it houses the Institut für Leichtbau Entwerfen und Konstruieren (ILEK) [Institute for Design and Construction of Lightweight Structures] under the leadership of Prof. Werner Sobek. The prototype structure was the worthy ending to an informative day within the framework of the second symposium of the series of events organized by DETAIL research and the research initiative Zukunft Bau [Future Structures].
The guests met here in the evening for a “get together”. And here the circle came together to discuss the theme of the day. In the preceding five papers with the focus “energy-efficient construction” experts in the most diverse subject areas showed that the concept of energy efficiency is not just flowery language, and that sustainable architecture is brought about above all through innovation, esthetics and a holistic consideration of energy.
As an example, the Hotel Louis in Munich abstracts the classical décor notion and is archetypal for Hild und K’s handling of its continuance. The conscious decision for a WDVS with its expressive and individual relief of the façade demonstrates that even in historically-formed surroundings, as is the case at the daily food market in Munich, the system is assigned an esthetic and economical significance.
Faraneh Farnoudi presented a current research project that goes still one step further: for the energy-related improved efficiency of an existing façade the creative quality goes hand in hand with the energy-related requirements. By reference to the isobars (the thermal flow within the façade section of the building) that have been made visible, Faraneh Farnoudi illustrated where the necessary insulation material thickness could be minimized. Therefore the insulation material is applied where it is required and in the process is only carried out to the extent that it is demanded by the thermal flow from the inside to the outside. This is no technological pie in the sky.
The insulation boards are pre-milled and then installed in the location on the façade determined by calculations in advance. The result is a shifting façade image which, despite energy-related indices as the basis of calculation, possesses a high esthetic appeal. “Insulate more attractively” paper (German) to download as pdf
Twelve years after the refurbishment a review was due to be carried out. In 2013 BASF initiated an occupier survey through the Hildesheim/Holzminden/Göttingen College with the specialist organization Trenscouting Hildesheim. The result showed that between 80% and 90% of today’s residents were satisfied or very satisfied with the residential area.
Added to this was a consideration of the topics material fatigue, amortization and CO2 saving over long-term operation carried out by the independent test institutes. From this it could be demonstrated that no material fatigue had taken place. Damages were shown to be related to processing defects (armoring carried out in the wrong level, sealing omitted). A further, astounding effect: due to the good energy-related indices the amortization of the energy-related refurbishments is now 15 years and not, as previously calculated, 30 years (referred to the so-called three-liter house, for a standard refurbishment even less than this). In sum, the refurbishment of the residential area led to a CO2 saving of 2,300 metric tons over the last twelve years.
Indeed the forward view was also important to Roland Streng: In the European project Eurhonet, the “European Housing Network”, BASF is working with the French architects Nicolas Michelin and Luwoge on an apartment building in the passive-house style developed as a basic type to be modified and offered on the European market. The first of these houses is currently being built in Darmstadt and will be completed in the early summer of 2014 on the basis of construction products currently available. Thus, it is not a pure research project but rather a contribution to the current architectural discourse. Paper “Resource efficiency through plastics in construction” (German) to download as pdf
The trend setting use of product solutions available at present is also a declared objective for the project of Prof. Jörg Hildebrand (Bauhaus University Weimar) sponsored by the Bundesministerium [Federal Ministry]. His key focus is hybrid elements in the façade. High quality systems such as vacuum-insulating glass (VIG) and vacuum-insulating panels (VIP) are state-of-the-art. However, the connection of individual systems into a hybrid, the glass-plastic sandwich elements and the resulting increase in performance are part of his research in Weimar. Above all, consideration of the advantages and disadvantages within the composition of the composite construction was the subject of his paper.
An essential point here is the permanent connection of the individual components and the diffusion resistance of the edge composite of the VIG elements: The bonding must guarantee a high degree of gas-tightness. In addition there is the consideration of the total energy passage in the filling of the system components with different filling media. Likewise, specific, static requirements are to be observed. Thus, the selective failure of the external glass level does indeed signify the partial loss of the insulation function, however, not the static failure of the complete composite construction. It does not, therefore, need to be replaced immediately. Paper “Glass hybrid elements” (German) to download as pdf
The project is led by Jochen Stopper at the TU Munich who presented it to over 70 interested guests in the lecture hall of Stuttgart University.
Fluid flow-through glass has been researched since 1953. However, only in recent years have results been documented that will make possible its widespread use in the façade sector. The fluid-glass principle can be briefly explained: colored fluid is injected between the individual glass levels that are provided with ingress and egress openings in the area of the bonded edge. The sheets are thereby darkened. In order to remove the discoloration, transparent fluid is flushed through so that the colored fluid is forced out again. This can be repeated again and again in closed circulation with the same result.
TU Munich is working on the project ongoing through 2017 with different fluids and is experimenting with their response characteristics and light transmission, together with the increased energy-related characteristics arising from this. Besides less daylight, a fluid-darkened sheet also permits less heat radiation in the space behind the façade. Thus, glass facades with fluid flow-through are ideal for use in high-rise buildings where it is not possible to work with externally-located shading.
According to Jochen Stopper early field trials in Dubai have progressed very positively. From the two identical test areas (5.0 x 3.5 x 3.0 m (L/W/H)) in Munich and Dubai the TU Munich researchers are promising the development of the first prototypes in the foreseeable future, which, even in climatic regions other than in Germany, will achieve good energy-related results. Indeed, the perfect fluid and the ideal system structure has not yet been found. Further work will be carried out on this, reports Jochen Stopper. Therefore, two further test containers are planned which will additionally provide, from 2016, new insights into the use of fluid-filled façade systems – also in the European sector. Paper “fluid glass” (German) to download as pdf
According to his theory the complex networking of the intelligent-home components in the coming years will yield simple components which communicate with one another, and thus make the solutions more coherent. However, the role of the architect in public will continue to be decisive. The roundly propagated energy revolution must, in future, be reflected in the buildings and become anchored in society. Hereby, topics such as e-mobility or innovative traffic concepts play a very large role.
One example of how architecture, energy self-sufficiency and mobility could intertwine in future, is the project “B 10” presented by Christian Bergmann. The prototype is a constituent part of the national project ”Schaufenster Elektromobilität” [“Electro-mobility shop window”] sponsored by the Federal government. The temporary structure will be completed in May 2014 and is located on a plot of land in the area of the Weissenhof estate in Stuttgart. The cubic building is thus in the middle of archetypes of the modern guest stay. It is planned to stay there for one year on a ground area of 14 x 6 m and be occupied during this period. Comprehensive monitoring will facilitate calculation of its energy efficiency.
With this project Werner Sobek is pursuing three objectives: to apply and extend the knowledge gained in precursor projects (R128, R129, P12), to interconnect the built environment, e-mobility and power generation and provide a perspective on future living. Due to the high level of prefabrication (timber-frame construction) and the so-called “energy racks” (bundling the intelligent home) the construction of “B 10” will require one week.
Besides the story-high, vacuum-insulation glazing that uncovers extensive insights into the living space and living environment, the textile covering of the cladding is conspicuous. The energy-related concept provides for 200% of the required power to be generated by the building. The excess is transferred during the operating phase to the Le Corbusier house standing within view of the building where it should supply the exhibition and two e-mobiles with power. Paper “The principle of the active house” (German) to download as pdf