ROCKWOOL Mineralwoll GmbH & Co. OHG
ROCKWOOL Strasse 37-41
Telefon: +49 2043 408-0
Kontakt: Rolf Ley
ROCKWOOL Mineralwoll GmbH & Co. OHG
ROCKWOOL Strasse 37-41
Telefon: +49 2043 408-0
Kontakt: Rolf Ley
Arcandor AG, Essen / Union Investment Real Estate AG, Hamburg
Bilfinger Berger AG, Niederlassung Warenhausbau
Prof. Dr. Gunter Henn, Henn Architekten
A facade sways like Marilyn's dress
Until spring 2009 the specialists from the Ebener GmbH from Bad Marienberg will still be occupied with the mounting of the around 15,000 m2 large aluminum perforated sheet facade in two construction phases at the shopping and experience center "Limbecker Platz" in Essen. Arched, colored shiny glass eyes are woven into the "shining shell" developed by Munich's star architect Professor Gunter Henn and shall make the building stand out both during the day and at night. Over 7,000 facade elements pre-curved in the workshop are installed - a lot of them unique structures, which will fit together to create an unusual swaying form, which is supposed to remind one of the famous, swaying dress of Marilyn Monroe.
Until the opening of the entire building complex - the first part was already opened in the spring of 2008 - up to 1,000 people will be occupied with completing the large project. The dimension of the project is also clarified by these figures: Until the completion, 125,000 cubic meters of concrete will have flowed and 13,000 tons of steel will have been installed.
Trend material perforated metal plate
"Perforated metal plate facades have become a popular trend", says Josef Spite, Construction Manager of the Ebener GmbH, responsible for the Essen construction site among other things, which was the largest one in the year 2008 for the medium-sized company. "What was required here, was mainly our full service. From the challenging planning to the prefabrication of all the facade segments to the installation, we were able to offer everything from one single source", reports Martin Bohn, Technical manager at Ebener. According to the plans of Professor Henn and a digital measurement on-site, the company first developed a 3-D model, which also presented the two spectacular entryways according to scale. "First the client, the general contractor, and the facade consultant needed to approve this model, before we started calculating the support structure and the shell", remembers Martin Bohn.
Soft sway earned through hard work
Around both entrances, the facade sways upwards in so-called crowns. It is supposed to remind one of the swaying dress of Marilyn Monroe in that famous movie scene, in which the actress is surprised by a gust of air from an air vent. On an area of approximately 600m², the façade here consist of an average of 2.1 m2 small perforated sheets, where one is not the same as the other. "The same applies to the steel support structure", reports Martin Bohn. "Not one steel truss resembles another. Support structure and facade are processed step-by-step according to exact installation plans, just like from a Lego-kit. Not one construction element could be mounted and installed in the wrong location." All the facade elements were pre-formed to size for radiuses between 19 and 200 meters in the workshop of Ebener in Bad Marienberg.
UK-profiles from own construction
Exactly four consoles at a height of 20 meters, each installed on an intermediate ceiling, carry the net weight and wind load of the facade construction around the rest of the building. "We installed the perforated sheet elements in a modular dimensions of 3,000 x 700 mm with four clamping profiles each", explains Josef Spitze. The support structure hereby consists of a pressed UK profile made from aluminum and newly developed by Ebener. To avoid heat bridges, the consoles were installed on Thermostopp (thermal stop) panels made from plastic. A space of approximately 400 mm remained between the insulation and the facade, in which extract and supply air ducts as well as other building HVACR systems could be housed.
Weather-resistant stone wool insulation
After the insulation of the facade consoles, the entire building sleeve was insulated with 80 mm thick stone wool panels "Fixrock 035 VS" from the Deutsche ROCKWOOL. 2,840 m2 of these insulation panels were used in the first and 3,000 m2 were used in the second construction phase. "Fixrock 035 VS" is used for the insulation of ventilated facades with open joints, as the black fleece lamination creates the optical effect of the shadow joint.
There is no risk that the insulation material will get penetrated by moisture, when moisture or driving rain gets to the "Fixrock" insulation boards through an open facade cladding as used in Essen. The special structure of the stone wool in combination with continuous hydrophobizing makes "Fixrock" permanently water-repelling and weather-resistant. Due to the diffusion openness of stone wool, no condensation occurs in the insulation material profile. Deutsche ROCKWOOL guarantees that the "Fixrock" insulation boards remain permanently dry - this also applies to the version without fleece lamination. Furthermore, the constant insulation effect of these facade insulation boards contributes to a reduction in energy use and therefore to a noticeable cost savings for the building owners.
"Fixrock" facade insulation boards are non-combustible (A1) in accordance with DIN EN 13501-1 and thereby make a substantial contribution to the preventative fire protection. They are suitable for the insulation of ventilated facades in all building heights and for all kinds of facade constructions, and are therefore indispensable for Josef Spitze: "We work almost exclusively with "Fixrock". Also because the price-performance ratio of this insulation product convinces us just as much as it does our clients."
No compromise regarding the insulation material
Due to a laminated black fleece, the insulation behind the perforated sheet facades remains completely invisible (shadow gap effect). The panels on the Limbecker Platz were fastened with five dowels per panel by request of the client, smaller cuts were glued and open cutting edges were laminated with the black fleece from the role. "We basically deliver a facade and a facade insulation, which exactly meets the wishes of the client and the requirements of the general contractor, in this case Bilfinger + Berger AG", explains Project Manager Josef Spitze from the Ebener GmbH. "This also includes that we install a laminated insulation on request and that we immediately repair possible transport damages during the installation. Also, when the laminating only serves for the optic - we are taking that seriously as well."
The acoustic insulation of an outer wall can increase by ten dB with an insulation of stone wool in combination with a ventilated facade. In view of the eight-lane traffic speeding past the building in the Essen city center, the insulation thereby brings an additional benefit, which especially is appreciated by the around 2,000 employees of the renters in the new mall.
Sturdy through stove enamel
Ebener GmbH exclusively processes perforated sheets and support structures with a powder coating according to GSB AL 631 for the facade. This extremely sturdy stove enamel renders the construction resistant against UV rays and other atmospheric influences. In general, it ensures very good weathering characteristics - an important factor with regard to the 35,000 m2 facade area that needs to be maintained and preserved.
The building structure of the new shopping and experience center on the Limbecker Platz in Essen reacts to the traffic flowing around it with its closed and soft form. For the creation of the facade, a facade competition was arranged beginning of 2005, which was won by the architectural office Henn from Munich. The terms "veil", "raise" and "adorn" were the inspiration for the central idea of his draft. "At the main entrances to the Limbecker and Berliner Platz, the aluminum facade leaves its horizontal line behind. The waistline remains, the hemline is raised. The lower facade finish is formed by a soft swaying motion which lifts up like a dress, where functional substantial features need to be emphasized", says Professor Gunter Henn. The veiling, closed metal paneling facade is lifted at the entrances - the subjacent transparent glass facade becomes visible with the shop windows. This picture reminds one of the world-famous movie scene in "The seven-year itch" with Marilyn Monroe and her dress, which is lifted up. The "dress" of the mall on the Limbecker Platz is adorned with sequins, which are illuminated in different colors during the night.
Shopping and experience center at a
rich in tradition
Over one-hundred years ago, Theodor Althoff founded a department store at the Limbecker Platz, which was supposed to quickly turn into the largest "Provincial department store" in the west of Germany. The renaming in 1963 rendered the impressive building to be the company headquarters of Karstadt AG. Due to the new construction, the plans which had been exiting for a long time to expand the entire area including the Karstadt head office, Sinn-Leffers and Karstadt-Sport to a large shopping center, were realized. The shopping center Limbercker Platz will be a center of the superlative and is supposed to give a true cosmopolitan flair to the Ruhr district. With a usable space of approximately 70,000 square meters and ca. 200 specialist stores, it will become one of the largest inner-city shopping centers of Germany.
Clients and operators
The real estate developer ECE and the Arcandor group are realizing the Limbecker Platz jointly with the Union Investment Real Estate AG (former DIFA). The Arcandor group brought in the most important properties for the construction of the large project and concluded a long-term rental agreement for major partial areas in the planned shopping center. ECE took on the project management, rental and the center management, andthe Union Investment Real Estate AG is involved with 60 percent in the project company realizing the project.
ECE Projektmanagement G.m.b.H. & Co. KG,ï ï Hamburg, has been developing, realizing, renting, and managing shopping galleries since 1965 and is the European market leader in this field. In the 94 centers operated by ECE, 10,000 stores on a sales area of 2.9 million square meters generate an annual turnover of 12 billion Euros. The ECE centers include the Schloss-Arkaden in Braunschweig, the Potsdamer Platz Arkaden in Berlin, the promenades in the central station Leipzig, and the Altmarkt-Galerie in Dresden, among others. Every center is a highly complex unique specimen with an individual architecture from historically oriented to futuristic, developed by the over 300 experienced ECE architects and construction engineers, as well as in cooperation with star architects such as Professor Dr. Gunter Henn or Renzo Piano. Being one of the largest planning offices of Germany, ECE develops entire city districts - either alone or in cooperation with renowned offices.
Ebener GmbH from Bad Marienberg is one of the market-leading companies in Germany in the field of facade profile technology. With over 120 qualified female and male employees and a production area of more than 4,000 m2, the company founded in 1989 created an environment, in which products of the top class are manufactured.