Self-supporting steel staircase | Marc O' Polo House of Product
2023, Stephanskirchen
Self-supporting steel staircase as an architectural highlight - imposing, functional and striking in design
In the Marc O'Polo House of Product in Stephanskirchen, a self-supporting steel staircase forms the central access point over three floors. The elliptically shaped staircase with its black lacquer finish, homogeneous underside cladding and sculptural appearance is a real eye-catcher in the entrance area. The self-supporting steel staircase combines functional architecture with a unique spatial experience.
In perfect architectural form
At the site near Lake Chiemsee, around 150 employees develop collections for the international fashion label Marc O'Polo. The headquarters were expanded with the House of Product in 2023. The three floors of the innovative new buidling offer an open, light-flooded working atmosphere with flexible utilisation and right in the middle: the self-supporting steel staircase as a design sculpture. It appears as a twisted band of steel that seems to float through the space. Without wall contact, with a surrounding gallery and generous air space on both upper floors, the staircase offers a view of its full height. The underside and lateral stringers of the self-supporting steel staircase form a dark, monolithic contrast to the setting.
Elliptical work of art with contrasting materials
The self-supporting steel staircase follows an ellipsoidal geometry with three different radii and up to four radius changes per flight. Its soffit cladding made of flush-welded flat steel sheets provides structural support and optimises the vibration behaviour.
Light European oak wood for the steps and handrails provides a warm contrast to the black steel structure. Special design details such as the continued steel and wood elements on the ceilings and landings as well as linear LED handrail lighting emphasise the remarkable appearance of the self-supporting steel staircase.
METALLART coated the visible steel components with a fire-retardant fire-preventive paint using a roller process - including intermediate sanding for a refined surface finish.
Insights
Project details
- 6-flight ellipsoidal layout, 3 different radii, up to 4 radius changes per flight
- Both-sided, parapet-high flat steel stringers (up to 1,120 mm) for fall protection
- Folded steel stair treads welded between the stringers; flight width: approx. 1,600 mm
- 3 landings, partly combined as stair head/stair foot landings + 3 intermediate landings
- Structurally supporting soffit cladding made of 5-8 mm flat steel elements
- Anchored to unfinished floor with steel plates and dowel connections
- Solid wood panel core with ‘European oak’ top layer
- Surface sanded and flame-retardant lacquered
- Glued to substructure, landing surfaces with joint division
- Handrail made of European oak, ⌀ approx. 40 mm, inside and outside
- Laminated, sanded, oiled and attached to the stringers with steel brackets
- Underside grooved for LED light strip (approx. 120 LEDs/m, warm white)
- Cable feed via the handrail, running downwards below finished floor at the stair foot/head
- Approx 36 running metres of railings on the ground floor, 1st and 2nd floor and on the gallery
- Vertical round bars (⌀ 20 mm) with spacing < 120 mm
- Flat steel handrail and bottom chord with flat steel frame as ceiling finish
Architecture
steidle architekten, Munich
Photos
Florian Holzherr
