Stair towers made to measure

Customised stair tower solutions for Burscheid apartment buildings

In Burscheid's Akazienweg, about 100 people live in a group of eight-storey houses, spread over 60 rented flats. With such a density of people, the constant observance and control of increased fire safety requirements always plays an important role. If this is not done, serious fire disasters can be the result. As a recent measure, two temporary escape stair towers have now been added to the buildings to provide an escape route alternative to the stairwells in case of emergency. Temporary escape staircases are usually used when conditions no longer meet fire safety regulations or when the necessary fire protection is to be restored through additional structural measures.

The contract for the construction of the stair towers made of scaffolding material was awarded to the company Gerüstbau Schmiedt from Kobern-Gondorf. The scaffolding company, which has been in business for more than 40 years, has already made spectacular appearances on special buildings all over Germany. Due to the increased demand, escape stair towers are now just as much a part of Schmiedt's service portfolio as the classic scaffolding services of working and protective scaffolding, bridge scaffolding, many special structures, etc. But the company loves challenges - even beyond the limits of "classic" scaffolding.

The scaffolding construction was planned and calculated in close cooperation with IBS Ingenieur- & Sachverständigen-Büro für den Gerüstbau Dipl. Ing. Joachim Specht & Partner from Schalksmühle. Joachim Specht was responsible for the project. The two companies have been working together as partners for many years, which also ensured that the construction site for this project in Burscheid was carried out smoothly and in compliance with all the strict general conditions.

Stair tower with a load-bearing capacity of 500 kg/m²

During the planning of the stair towers in Burscheid, those responsible were faced with three serious challenges:
1. the load-bearing capacity of the entire construction, i.e. on all stair flights and landings at the same time, had to be 500 kg/m².
2. the exit heights had to be adapted to the local conditions with centimetre precision.
3. despite different stair heights (1.00 m, 1.50 m and 2.00 m), the same step size should be maintained as far as possible.

The top exit height of the first stair tower for seven storeys was exactly 18.10 m, that of the second emergency staircase for eight storeys 20.85 m. Both towers were to have a walking width of 1.00 m, 1.50 m and 2.00 m. The staircase was to have a top exit height of 18.10 m. Both towers were to have a running width of 1.50 m.
The Scafom-rux modular scaffolding system RINGSCAFF was used for the scaffolding construction, in combination with heavy-duty stairs and system-free accessories. Due to the increased load capacity, the basic scaffolding had to be considerably reinforced, which in turn led to an extremely high dead weight with a high surface load. For this reason, the stair towers were founded on double, load-distributing concrete slabs. However, not without first excavating the soil down to a load-bearing layer.

Centimetre-precise adjustment of the exit heights

In order to guarantee the increased load-bearing capacity of 500 kg/m² at every point of the stair tower, Gerüstbau Schmiedt strengthened the individual uprights in such a way that they became quasi three- or even four-belt supports by means of additional parallel uprights. The individual RINGSCAFF standards were connected with double wedge couplers.
Escape staircases are subject to very special regulations. Among other things, no tripping hazards or other disruptive factors may impair smooth evacuation in the event of an emergency. In order to make the transition to the existing building, Schmiedt's fitters installed ramps made of steel decking with pipe support. This allows barrier-free access to the escape stairs from the building.