Photo of a construction site on a forecourt in front of a church

General refurbishment of the cathedral steps in Cologne

Location:
Cologne

Build time:
04/2021 - 11/2022

Client:
City of Cologne

General refurbishment of the cathedral steps in Cologne

Cologne Cathedral is one of the most visited sights in Germany and has been a World Heritage Site since 1996. The staircase was built in 2005 on the occasion of the Pope's visit and connects the station forecourt with the cathedral square. Every day, 250,000 passers-by use the granite steps of the 70-meter-wide staircase.

The staircase is located on a bridge construction and consists of three flights of stairs. Due to the heavy load caused by high pedestrian traffic and sunlight, the individual block steps have shifted, resulting in edges and protrusions and therefore an increased risk of tripping. In view of this, it was decided to remove all the granite steps and slabs and to replace the waterproofing underneath.

Success with an innovative logistics concept

As part of the waterproofing work, an area of approx. 1400 square meters was provided with a surface protection system (OS10). The approx. 1100 block steps were removed individually, extensively cleaned at a different location, partially provided with contrasting strips and then reinstalled at the same location. Steps and slabs that were already damaged were replaced. An in-house component tracking system was used to maintain an overview and ensure this complex 1:1 replacement. Finally, all steps were anchored back twice with a stainless steel construction to prevent them from shifting again.

In addition to the steps, approx. 280 landing slabs and approx. 1,200 adjacent slabs on the station square and the cathedral slab were taken up and laid again in drainage mortar.

Contribution to accessibility for visually impaired people

In addition to the contrast strips on the individual steps, attention strips were also installed in the area of the cathedral slab. These ensure better visibility and guidance for visually impaired people and should therefore contribute to improved safety.