The staircase rests on two points: at the top on the landing, at the bottom on a foundation beneath the paving. In between, it carries itself.
That is not a gimmick but a decision with consequences – for the appearance, for cleaning and for the effort involved in installation. This project is a good example of why a self-supporting exterior staircase is often the better solution and what matters in its execution.
What an exterior staircase on an existing building is needed for
Floor-to-ceiling windows have long been standard on upper floors – but usually there is no way down from there. An exterior staircase turns the window into an exit: as direct access to the garden, as separate access to an upper residential unit, or as a second escape route when the building authority requires one.
For this project a self-supporting design was specified – without additional posts between the bottom step and the landing.
Why self-supporting works
In this type of construction the two stringers take on the load-bearing function. They are dimensioned so that they span the entire run – the steps hang in between and carry nothing themselves. At the top the staircase is connected to the landing, which is anchored to the wall via brackets. At the bottom it rests on a short entry platform that sits on a foundation beneath the paving.
Every exterior staircase needs a foundation at the bottom step. The difference is that no further ones are added: every additional post would need its own foundation, and with it excavation in the already finished surface – and in the end the post often stands exactly where you want to walk.
The result is a continuous line from top to bottom, no post in the way, and the area underneath stays clear – which makes sweeping and clearing snow noticeably easier.
What this requires: a load-bearing wall, an adequately dimensioned foundation at the bottom step and a sound structural analysis. Self-supporting does not mean „without calculation“, but that the loads are transferred elsewhere. That is why every staircase of this kind calls for well-thought-out connection detailing – and why we manufacture in accordance with DIN EN 1090.
Surface: galvanized and coated
The staircase is hot-dip galvanized and additionally powder-coated in the color DB703. That double treatment is deliberate.
Hot-dip galvanizing still protects the steel even when the layer is damaged – the zinc sacrifices itself for the steel underneath. A powder coating alone cannot do that: if the paint layer is damaged, moisture creeps underneath and the rust works its way sideways.
The combination of the two is called a duplex system. Outdoors it lasts considerably longer than either of the two layers on its own – and you still get the color the building calls for. DB703 was the obvious choice here because the parapet, window frames and balcony structure are matched to it.
We have described this in more detail in our guides on hot-dip galvanizing and powder coating.
Treads made of steel grating
Outdoors, grating treads are almost always the right choice. Rain runs through instead of standing on the tread. A good part of any snow falls through by itself. And the surface is inherently slip-resistant, without anything having to be reworked.
The price for this is a visual one: grating stays silvery galvanized and contrasts with the dark frame. Anyone who does not want that can have the treads coated as well – but then loses part of the self-cleaning effect.
The railing: deliberately plain
Vertical infill bars, a rectangular tube as a handrail, no ornamentation. This design ages best – it was right twenty years ago and will still be right in twenty years.
Vertical bars also have a practical advantage over horizontal ones: they make it harder for children to climb up. Railing height and maximum bar spacing are governed by the requirements of DIN 18065 and the state building codes. What applies in each individual case is explained in the railing guide.
We also produce the same design separately as an exterior stair railing – for example when an existing staircase is in good condition and only the railing needs replacing.
From inquiry to installation
For a reliable quote we need three things: the height from the top edge of the finished floor to the exit, the available space in plan, and a photo of the situation. That is usually enough to say whether a self-supporting design is possible or whether a post would be the more sensible solution.
Once the order is placed, things get precise: we survey the building with a 3D scan and design the staircase in 3D CAD – planned by master craftsmen. You receive the design for approval and see your staircase on the building before the first piece of steel is cut. Only then does production begin.
This staircase is a custom fabrication. Length, rise-to-run ratio, connection points and color depend on the building – there are no standard dimensions for that and therefore no catalog price.
Exterior stairs made to measure · Exterior stair railing · All exterior stairs · All stair railings · Reference photo gallery
