Structural challenge high above Hamburg’s rooftops

Beyond the port and the Elbphilharmonie concert hall, Hamburg has numerous other highlights in store for visitors as well as the odd curiosity. Whether or not you count Sierichstraße in the city’s Winterhude district among them is probably a matter of taste. It’s one of the few streets in Europe that changes direction in the course of the day to accommodate commuter flows. Whereas in the mornings, cars are allowed to use its two lanes to travel into the city centre, from the afternoon onwards traffic is only permitted in the opposite direction. The street is lined with historic villas and large apartment buildings. One of these stately blocks of houses is to be raised by 1.5 storeys to create modern penthouse flats, which given Hamburg’s weather is only feasible with a weather protection roof. Hamburg-based Busch Gerüstbau GmbH & Co. KG were charged with planning and implementing the essential facade scaffolding as well as the 2,000 m² Keder Roof XL solution.

“We need facade scaffolding and a Keder Roof if we’re going to add an extra story to a building. What at first sounded like an everyday assignment over the phone became bigger and trickier by the day when it came to the planning and implementation”, explains Christopher Busch, Managing Director of the Hamburg scaffolding specialist of the same name. Sierichstraße – one of Hamburg’s busiest streets – had to be narrowed to a single lane in the area of the facade to make room for the crane and the construction site equipment. So as not to occupy more public space than absolutely necessary, the footpath was turned into a covered pedestrian tunnel using Layher Allround Scaffolding and Protect System elements. A 70 m long and up to 6 m wide platform was erected over it and also over the whole of the front garden. “Anyone who has ever passed by here during the rush hour will know that every inch of road is vital. That’s why covering over the garden completely was the best option. It means we can store all the required building materials temporarily without any problem during the 18-month construction period and reduce the disruption to traffic to a minimum”, adds Stefan Grasnick, the site supervisor responsible for the project.

A real structural challenge
All in all, approximately 7,400 m² of Layher scaffolding was erected at the site by the Hamburg scaffolding specialists. Before an extra storey could be added to the building, the existing roof first had to be dismantled, with huge implications for the Layher SpeedyScaf facade scaffolding, because it made it impossible to anchor it into the facade on the top three floors. “We went round in circles a few times with this structural dilemma, because the entire Keder Roof XL also rests on the SpeedyScaf and so the upper layers had to be provided with additional vertical reinforcement.” Stefan Grasnik is an experienced scaffolder but “It proved to be quite a battle of materials all the same. We installed a further 1,330 linear metres of lattice beams horizontally and vertically on the SpeedyScaf alone to make it all structurally safe as well.” Three scaffolding ‘tables’, each weighing more than 2.3 t, were hooked into the roof part, so that the overall scaffolding structure would be even better equipped to meet the tough challenges. René Stender, Layher Area Sales Manager for Hamburg, is visibly impressed: “The structural engineering consultants did a truly fantastic job here”. “These supporting structures help to make both the entire scaffolding and the over 2,000 m² Keder Roof XL fit to withstand the endless vagaries of the weather.”

Success always comes from teamwork
“A project like this relies on teamwork – and I don’t just mean the people in the construction crew or in the office. The cooperation with our customer, other trades,

the structural engineering consultants and – last but not least – Layher is equally fundamental for the success of our work”, Christopher Busch comments. The close collaboration with the structural specialists and Layher’s regional contact played a particularly important role in this project, because the requirements have changed frequently, meaning that new calculations and a lot of new material have been needed for the construction site at short notice. Busch could not be more satisfied: “This clearly shows the advantages of a good network in which everyone pulls together to realise a project professionally. We’ve just had an employee trained by Layher directly to use the LayPLAN CAD software, and we’ll be able to plan and implement our projects even more efficiently in future”, Stefan Grasnick reports. Seeing all the details of a scaffolding design on the computer upfront opens up immense possibilities. Not only can the required materials, logistics and assembly steps be planned very precisely; architectural or structural challenges can also be identified at an early stage and solutions worked out on the PC. “Scaffolding is increasingly digital – and we’re at the forefront, constantly leveraging the benefits”, the two professionals conclude, not without pride.

Hamburg’s economic miracle
The modern premises not far from Hamburg Airport are meanwhile home to 30 permanent employees. The company was founded by Gerhard Busch in 1963 as a specialist painting and decorating business during the “period of the German economic miracle”. in 1988, the scaffolding segment was spun off into Gerhard Busch Gerüstbau GmbH. Busch has trusted in scaffolding solutions from Layher from the outset, and to this day works exclusively with Layher’s Integrated System. Christopher Busch, an engineering graduate and son of the founder, joined the management team in 2003 and has been at the helm of the steadily growing firm ever since. As “Hamburg-born and bred”, they’re especially proud of their work at well-known Hamburg institutions like the Davidwache police station, the Alster Arcades, the airport and Hamburg State Opera House. “We’ve a reputation among our customers for quality and expertise – something we have in common with Layher, who I’d definitely say stand for similar values”, Busch concludes.