Aim high – safely and economically

Renovation of the Königstein church with ALFIX façade scaffolding system

 

Roof and façade work was carried out as part of necessary maintenance work on the Marienkirche in Königstein in Saxon Switzerland. In order to enable a smooth renovation of the building erected in the 18th century on the Schreiberberg, the sophisticated baroque cubature was scaffolded using ALFIX 70 façade scaffolding (approval number Z-8.1-862) in combination with system-independent aluminium and steel lattice girders.

 

ALFIX 70 facade scaffolding system including stair tower

 

Thanks to the modular system with prefabricated components with an economical number and arrangement, a scaffolding height of approx. 36.00 m was quickly achieved to reach the eaves of the church tower. The wall distance of the building required that the working scaffold (developed in load class 3 with 200 kg/m2 according to the standard EN12811 and with the width class W06) be erected in sections using internal ALFIX brackets measuring 0.36 m.

It was particularly important that the historic building with a sandstone exterior be affected as little as possible, and that the church nave not be stressed by the scaffolding or traffic loads. With this in mind, Bindig Gerüstbau GmbH coordinated with the ALFIX GmbH Project Department to develop a concept using self-supporting scaffolding in the rear third of the church tower.

 

ALFIX self-supporting facade scaffolding planned and erected

 

With the help of lattice girder wall connections and short lattice girders (with a maximum length of 3.00 m), a support was created to absorb load weight from both the bridging on the back of the church above the nave as well as from the lattice girder overhangs on both of the side scaffolds. Solid heavy-duty brackets were intentionally avoided in order to ensure a gentler assembly for the scaffolders and an easier handling.

The ALFIX aluminium lattice girder played a special role in the façade scaffolding for this project, serving as a bridge over the church nave and enabling manual assembly without a crane. The system-independent steel lattice girders, which were positioned at right angles to the façade at the lattice girder wall connectors, were anchored to the façade with the necessary fasteners according to the statics. Pull-out tests and load tests provided the verification values necessary to determine the required number of girder wall connections. This special solution was implemented twice more on the back side of the church tower. A large bracket was simulated on the side scaffoldings using a combination of lattice girder wall connectors, short steel lattice girders and a tension rod made of scaffold tube and couplers.

 

3D Planning and assembled construction: Bracket made using lattice girder wall connector, lattice girder made of steel and tension tube

 

The lattice girder wall connector is a system-independent accessory which is able to be used for many special solutions. Thanks to the basic construction on the back of the church and along both sides of the nave, the system-independent aluminium lattice girders could be installed parallel to the façade in order to accommodate the field grid of the working scaffold. This project used all standard lengths of the ALFIX facade scaffolding system from 0.73 m to 3.07 m which were optimally combined in order to surround the church tower in accordance with the requirements. A load tower with a lift and an integrated stair tower made using approved ALFIX aluminium platform stairs were positioned and installed in front of the church for the quick and consistent delivery of materials by the trades. To keep the anchoring points in the sandstone to a minimum, the load tower was stabilised using vertical lattice girders. From the platform upwards, the ALFIX stair tower was integrated into the working scaffold on the façade to ensure safe access up to a height of 36.00 m.

The scaffolding construction was completely enclosed with dust protection nets, as the public walkways are highly frequented in this tourist area. Entrances to the church were provided with the appropriate bridges, thus ensuring the continued safe operation of the church as well as the secure use of the surrounding streets.

Thanks to the close cooperation between the scaffolding manufacturer and the scaffolder, as well as thorough preliminary planning in the ALFIX GmbH Project Department, this complex project was able to be developed and was already precisely prepared and digitally visualised on the PC in the planning phase. The 3D visualisation of this project can be seen at https://autode.sk/3ZQLMnE or by scanning the QR code in the image below.

All product information, instructions for assembly and use, and approvals can be found on the ALFIX website.