These imposing curved design stairs featuring parapet-high steel stringers were constructed for a new single-family home near Zurich. To illuminate the design stairs in an indirect way MetallArt realised lighting coves at the outer stringer of the stairs serving at the same time as handrail. A parapet-high balustrade made of steel plates combines the railing at the slab edges and the cladding of the ceiling frame. This results in the homogenous and sculptural appearance of these design stairs.
Curved balustrade stringers for design stairs
The two-flight steel stringer stairs show a flight width of approx. 1,100 mm. They connect the basement with the ground floor and run evenly rounded and in the same design to the first level of the building. The height of the parapet-high flat steel stringers varies between 1,270 and 1,320 mm. With their dominating character they present the fall protection of the design stairs. The staircase landings on the ground floor and on the first floor are constructed as a platform in the shape of a quarter circle.
Tread step construction and platform of the design stairs
- folded steps made of 5-6mm thick steel sheet (or according to structural requirements), welded in between the stringers
- bent down at the front side
welded upwards at the rear
closed treads and risers
wooden covering for the folded steps, finished on site
The two head landings of the design stairs were realised according to the design of the tread steps. To meet the structural requirements there are additional transverse ribs along the bottom of the stair stringers.
Handrail as lighting cove for LED illumination
To allow the installation of an LED handrail lighting system on site the MetallArt experts mounted a stylish cove at the outer stringer of the design stairs which constitutes at the same time the elegant handrail for the stairs. For this outstanding feature an horizontal flat steel section was welded on the upper side of the balustrade stringer and complemented by a vertical downward flat steel element.
Curved horizontal balustrade as frame for the ceiling
Its in particular the distinctive parapet-high steel balustrade due to which the design stairs get their homogenous appearance. The steel sheets show a thickness of 10-12 mm and are executed equivalent to the stairs' stringers. Beside its function as railing is constitutes at the same time the ceiling frame and partly masks the slab edges and the floor structure. This element of the design stairs has a diameter of approx. 3,000 mm and was realised as full circle on the ground floor and as semicircle on the first floor.
Beside the production and assembly of the design stairs MetallArt was responsible for the verifiable structural calculation for the stairs and railings.
MetallArt would like to thank the architects at the office skizzenROLLE in Kirchberg (CH) for the successful cooperation in this staircase project.