Four Frankurt building, the fresh building of a contemporary cityAcclaimed architect Ben van Berkel’s building ensemble “FOUR Frankfurt” is “the fresh vision of a contemporary city.” Facade specialist Dobler Metallbau supplied the facades for two of the four towers in Frankfurt. Roto Aluvision and its team of advisors from Roto Object Business assisted Dobler by developing a special Turn-Only hinge side. This hinge side will be presented for the first time at BAU 2023 in hall C4, stand 303.

Installation of the double-element facade on building “T4” commenced mid-March 2022, with around 1,800 Turn-Only sashes. Work on “T1” began in mid-June 2022, with 5,000 Turn-Only sashes, which are 2,900 mm tall and between 838 and 1,202 mm wide. 

With the architect’s aesthetic concerns in mind, Roto Aluvision developed a fully concealed Turn-Only hinge side that meets Schüco’s profile-specific requirements. For instance, there is the option to install an opening restrictor, limiting the opening of the window to 40°, to ensure the sash does not damage the load-bearing concrete support when opened. 

The Turn-Only hinge side is designed to be removed quickly, even on hard-to-reach sashes. Once the safety screws on the bottom pivot rest and top hinge are loosened, the bolts can be removed from any direction. Additionally, the hinges height can be adjusted by ±1 mm for an easy on-site installation. 

Each bottom corner hinge was combined with two central hinges to ensure tight sealing and optimal load transfer of the 440 lbs. (200 kg) sashes.  

Schüco Engineering and Roto collaborated to develop the window sashes and tested them in the Roto International Technology Centre (ITC) in Leinfelden-Echterdingen. As an accredited test center, the Roto ITC can conduct a durability test of over 20,000 cycles and certify its success and completion  

All hardware components from Roto Aluvision used for the “FOUR Frankfurt” project meet the requirements of corrosion protection class 5, offering the highest protection against damage to functionally relevant surfaces.  

Project developer Groß & Partner and the architects emphasized the importance of close collaboration between Roto Object Business and Schüco Engineering “Roto Object Business was established to support the successful realization of exceptional architecture,” explains Jordi Nadal, Roto Aluvision Managing Director. 

Dipl.-Ing. Gerald Spiegel, project manager for “FOUR Frankfurt” at Dobler Metallbau, confirms: “When industry partners like Roto and Schüco are involved and contribute their expertise, it means added security and quality for us and the client.” 

The advisors from Roto Object Business help industry specialists with planning and designing innovative new building elements by configuring custom hardware solutions. They are able to demonstrate the technical feasibility and various hardware designs for different demands in a short period of time. 

The hardware solution is then visualized in a prototype, making it easier to discuss production optimizations and speeds up the planning process.  

The scope of services also includes training the window manufacturer’s staff during the initial production stages, while a customized logistics concept ensures short, on-time deliveries.  

These services are supplemented by project-specific documentation and reference-work containing all hardware-related information about the project, and an expert after-sales and spare parts service. 

Since Roto Object Business was established in 2014, the team’s specialists have provided their services for projects globally. “Today, Roto can certainly be considered a highly valued partner of many aluminum façade specialists worldwide. At BAU in Munich, we will offer attendees a platform to exchange ideas related to projects and showcase different/diverse custom solutions,” sums up Nadal. In a specially set up consulting center outside the booth, customers and prospects will have the opportunity to learn more about hardware solutions for aluminum systems and the services provided by Roto Object Business. 

About Roto North America

Roto North America is comprised of Roto Frank of America, Inc. in Chester, Connecticut and Roto Fasco Canada, Inc. in Mississauga, Ontario, Canada. Both locations manufacture window and door hardware, which offers solutions for North American and European applications. RFA and RFC are wholly owned subsidiaries of Roto Frank Fenster- und Türtechnologie GmbH, a global leader in window and door hardware, with 15 production plants and more than 30 subsidiaries worldwide.

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