XERVON Austria’s scaffolding experts came to the rescue recently drawing up a bespoke solution to erect a scaffold around one of the turrets of the Votive Church in Vienna – saving the church authorities a large sum of money and, once again, demonstrating their outstanding technical expertise.
Over the last twenty years, the scaffolding specialists working at XERVON Austria have often been called on to erect scaffolds around different sections of the Votive Church. Their client, the St. Josef’s Foundation of the Archdiocese of Vienna (responsible for historic religious buildings), is one of the company’s key customers. Consecrated in 1879 following 23 years of building work, there is always some part of the church that needs renovating. The Votive Church is considered to be one of the world’s most important neo-Gothic religious buildings. The decision had been made to build this church as a votive in gratitude for the sparing of Emperor Franz Joseph 1 after he survived a failed assassination attempt on 18 February 1853.
An extensive list of restoration work has been planned for the church’s façade, roof, roof truss and windows. Work is currently being carried out on the so-called ridge turret – a 20-metre octagonal tower built 42 metres above the ground on the ridge of the roof at the point where the nave and transepts meet. With a diameter of 4.5 metres at its base, this very pointed turret rapidly becomes much narrower as it rises upwards. It is made of a steel skeleton frame covered in metal sheets. A number of different experts – tinsmiths, metal workers and metal restoration specialists – are now in the process of restoring this structure from their safe work platform on the scaffolding erected high up in the air.
Consecrated in 1879 after 23 years of building work, the Votive Church is one of the world’s most important neo-Gothic religious buildings
Engineer Harald Sauerwein, XERVON Austria’s site manager responsible for work platforms and scaffolding, believed that the biggest challenge of this particular project was designing and planning a cost-effective base which the scaffolding could rest on: “There were a number of difficulties to be overcome here. On the one hand, the slate roofs surrounding the turret had themselves just been restored and so it was essential that they were not affected by the scaffolding in any way. Having said that, they are all so steep that they couldn’t have provided a stable base anyway.” The Archdiocese’s planning office had been resigned to the fact that they were going to have to pay for a steel base structure to be built – something that would not only have been very time consuming to set up but also very expensive.
Within no time at all however, XERVON’s specialists had come up with an alternative that was considerably less expensive: working closely with the structural engineers at the planning office, they developed a concept that involved scaffold lattice beams being placed through the turret openings. These were used as the base for the scaffold, which was then erected around the tower and consists almost exclusively of lightweight aluminium material. The scaffold structure has been designed to bear a weight of 2 kN/m² – more was not possible as this was the maximum load that the church’s roof truss could bear.
Experts at work: the scaffolding experts designed and erected a safe platform so that the restoration specialists can carry out their work
Logistics also played a vital role in this restoration project as the church is situated right in the centre of the city: “It was clear from the start that we would need to have a mobile crane on site whilst the scaffolding was being erected, so that the scaffolding material could gradually be passed up as it was needed. The ridge turret’s exposed position and the lack of storage space on the scaffolding meant we had no other choice,” said Harald Sauerwein explaining the relatively time-consuming option used to get the material to the roof. The scaffolding material will soon have to be removed in exactly the same way as the restoration work is expected to have been completed within just three months. And then yet another successful step will have been taken to preserve the Votive Church. A successful but small step as the Archdiocese’s planning office is expecting the restoration work on the outside of the church to take around 20 years and cost 32 million euros. There are, therefore, bound to be a number of other opportunities in the future for the XERVON scaffolding experts to demonstrate their expertise.
The special features of this project: an ingenious structure and smart logistics