The Steiff factory and the birth of curtain walling

The question of what building in history has the first curtain wall hides a tough academic battle. Here - as almost everywhere - Europeans and Americans diverge. I don't have a strong favourite. What I have is a list of the first curtain walls erected before 1950 that matter to me; and they happen to be located at both sides of the Atlantic.

Among the Europeans, the Fagus headquarter by Walter Gropius, built in 1911, is celebrating its first 100 years now. Among the Americans, the Halliday building in San Francisco (1917) is a must; same as the Equitable Building in Portland (1946), a forgotten jewell from Pietro Belluschi. Now that I think of it, it would be good to re-visit most of these great oldies in future posts.

The east block from 1903 is the front pavilion to the left. The others were built between 1904 and 1908. Picture from the early 1920s.

This post is devoted to one of the first real curtain walls (not a shop front or a wintergarden) ever built, the east block at the Margarete Steiff AG factory in Giengen, erected in 1903. One thing can be said for sure: this was the first double skin facade ever built and - not surprisingly - it had to be located in Germany. Most of the information for this post comes from a paper whose title couldn't be more clear: "The invention of glazed curtain wall in 1903 - The Steiff toy factory". The paper was presented at the 3rd International Congress of Construction History (Cottbus May 2009) and was written by A. Fissabre and B. Niethammer from RWTH Aachen University. More information about the Steiff factory can be found at the Docomomo Webpage on the building.

Europe’s most celebrated soft toys, the teddy bears with a button in their ear (‘Knopf im Ohr’) are still manufactured in this all-glazed factory building located in the small town of Giengen, 32 km north-east of Ulm. Margarete Steiff (1847-1909), a native of the town was partially-paralysed at the age of 18 months, but from a dressmaking studio in her father’s house she established a successful company making felt toys. Her nephew Richard Steiff was largely responsible for the company subsequent growth. 

The original factory building as it is today. Note the diagonal bracings at the large elevation.

Between 1902 and 1903 Richard Steiff took two revolutionary steps: to include bears (sitting bears to be precise) as part of the company toys portfolio and to design a new factory building to cope with the increasing international demand of felt toys.


Teddy bears for the American market were in fact the reason behind the construction in 1903 of a new iron and glass building, 30m long, 12m wide and 9.4m high, with an outer shell consisting of a continuous double-glazed wall and a flat roof. The three floors within are supported on iron lattice-work columns. The iron castings and forgings were designed and provided by Eisenwerk Munchen AG, a German contractor. The east building was subsequently extended with two more pavilions between 1904 and 1908, built in timber structure for economic reasons but all with the same double glazed facade. 

Richard Steiff's intention realised: an all-glazed, well-lit building to increase productivity in toys assembly

Inner view of the Fagus office wing, Gropius 1911

Look at the image above, and compare it with similar images of the Fagus factory in Alfeld by Gropius, to be built only eight years later. In Alfeld they made shoe trees, here in Geingen they made felt toys. Both activities required natural light. Alfeld is located at the north of Germany, Geingen is at the sunnier south. Natural light inside the Steiff factory is everywhere; if it were not for the clothings and the bulb lamps the image above could be almost contemporary. Look at the curtain drapes at the facade corners: they were there to protect from excessive sun radiation in summer.

Was Richard Steiff (the company founder's nephew) interested in a brand new industrial aesthetic or was he looking for an engineering ideal? Clearly not at all. He was a toy industrialist himself - he was looking after a continuous workshop plan, well illuminated, where productivity could raise and costs be kept under control. He was also in a hurry: in 1902 the company had received a first order of 3,000 teddy bears from a client in the USA, and subsequent orders were expected. More production space was needed but it had to be efficient, well lit and built quickly.

Richard Steiff with a teddy bear

Richard may have taken over some constructive ideas from his father, Friedrich, who was employed in the building sector. According to the paper  by Fissabre and Niethammer, Friedrich Steiff might have been influenced by new iron-glass constructions when he visited the Great Exhibition in Chicago in 1893. Upon receiving these ideas from his father, Richard did not only try to realise them but also to improve them. Maximising light was not an easy task as the planning authorities feared workers would go blind in a glass house. But the permission was given and construction could finally start.

Richard Steiff contracted the Eisenwerk München AG company to design and build the structure of the new factory. It remains unclear who proposed and decided it, but steel was the obvious material for a quick and fire-proof structure. The plans and details of the riveted and wind-braced steel frame were drawn by Eisenwerk München, as shown in the plan drawing shown here below. The three-storey loft, covering an area of 12 x 30m, has a slightly inclined single-pitch roof made of galvanised iron sheet. Inside it is divided in three naves each formed by five bays, punctured by rows of six load-bearing columns each.

Second floor plan as shown in the building-permission documentation, 1903. Note the L-shaped ramp for Ms Steiff's wheel-chair extending from bottom left up to top right.

The main structure of the building (located at the corners) consists of four L-shaped external pillars, riveted on several plates and angle sections. They are linked at the bottom with a lattice truss running around and set in concrete, thus guaranteeing the solid fastening of the frames. The lattice truss is also the basement of nine facade columns of I section set in each of the longitudinal walls, transmitting the perimetral forces onto the ground. The intermediate and short-side facade columns are composed of two U-shaped beams, conntected by small sheet metal streps (see images of the interior above and of the construction below). 


The load-bearing structure is reinforced by two long diagonal braces on each side of the long facades and cross-butressed ceilings at each floor level. This composition provides three-dimensional stability with a minimum dead load. Prefabrication and dry-fix connections are a fundamental part of the concept, a combination between Marcel Lods and Mero structures but built fifty years before. Even the Maison Dom-ino concept by Le Corbusier would come much later, in 1914-15.

Construction site in 1903. Note the four corner columns, the nine longitudinal pillars above the lattice truss and the intermediate set of six columns each. The top beams and the diagonal bracing are not instaled yet.

Now it's time to talk about the envelope, the really revolutionary innovation in this small building. The external cover consisted of a double skin façade on all elevations. The inner glazing skin goes from the upper edge of the floor to the lower edge of the ceiling, whereas the outer façade covers the total height of the building. If the inner skin could be understood as a large glass shop-front, not dissimilar to other examples in New York, Chicago or Berlin, the outer skin is nothing but a pure curtain wall. It floats above the facades suspended from the top level; it runs continuously around all three floors, it is attached to the columns to transmit wind loads, and it was conceived as a cavity between two transparent skins to improve its thermal performance whilst allowing natural light.

The columns are located inside the air cavity

The facade had been planned from the very beginning as a double-skin construction for heat insulation. The thermal insulation is achieved through an air cavity of around 25cm floating above the envelope. Air exchange is possible by opening box-type windows in every floor, which don't interchange air with the cavity. Additionally, the building was equipped with a low-pressure steam heater - new at the time - that kept the internal temperature stable in winter.

Corner detail and section / elevation, taken from Glass Construction Manual, Schittich et al 1999

What about summer conditions and solar heat radiation? It is clear that the workers did not become blind due to excessive light, but they surely were not happy working in summer under external high temperatures, equally high inside the building. How could solar radiation be mitigated? First, the glass is not transparent but matt, a cheaper version at the time. Matt glass has a slightly lower solar factor. Second, the factory owners used a combination of curtains and cross-natural ventilation to keep temperatures at least not higher than the outside ones. Air conditioned, already invented by Carrier, was of course not an option here, although ventilators were installed later on. It is ironic that exactly the same problem and the same 'natural' mitigation strategy was followed at the Crown Hall building in the IIT campus in Chicago, many years later. Mies van der Rohe was simply learning the same hard lesson again.

Vertical section of the double skin facade, taken from Fissabre & Niethammer 2009. Ech glass pane is 3mm thick. The cavity was communicated along the whole height.

One last detail that struck my attention when preparing this post: where are the stairs? As the plan above shows, there seem to be no stairs inside the factory space. Instead, a ramp was designed that, starting from the ground floor, provided access to the first floor and to the second one from the outside. The main reason for this unusual feature has to be found in the company founder and boss, Ms Steiff's handicap. I can imagine Ms Steiff as a strong minded woman, travelling up and down the ramp in her wheel chair. But there is a second reason, also quite practical. Building permission is given (and taxes are paid) based on the built covered space. A nice internal stairbox would have detracted a noticeable percentage from the net usable area. An external ramp, especially if it was required by a handicapped person, was an excellent alternative that had no impact on the inner space. Again, German passion for efficiency at its most!

The ramp at the back of the Steiff factory providing access to the first and second floors. Picture taken around 1903-04.

What was the influence of the Steiff curtain wall in the European architecture? The hard truth is that there were no lessons learnt from this early example of curtain wall application, simply because nobody decided to pay any attention. Why was the Steiff factory so completely ignored at the time?

• First, because the project was not signed by an architect. We now know it couln't be otherwise: an architect would have considered the whole concept too unpalatable. It was not until Gropius developed what he had learnt working for Peter Behrens at the Fagus factory that light was made upon the curtain wall as a respectable facade solution. 
• Second, the place was not central to anything. Giengen is still today a nice small town, with a German mid-size industrial park devoted to toys and fire-proof systems. It was not in Berlin, the Rühr or Frankfurt.
• Third, the company was not AEG or Messerschmidt. Steiff is well-known today but only among toy collectors. It was completely unknown at the beginning of its growth in 1903.

Scheerbart (left) and Bruno Taut at the Glass House, 1914

All said, it is a real pity (or a shame) that architectural critics were so blind about what was happening around them. Sigfried Giedion was too young, Muthesius or Tessenow were too interested in the handcraft work to notice about steel, glass or modern factories. The glass guru of the time, the poet Paul Scheerbart, would not write his very influential "Glasarchitektur" until 1914. And by then things had taken another direction. In summary, Richard Steiff was not the right man, not in the right place, and definitely not in the right time to become influential. He had arrived too early.  But he still deserves a big part of the credit. Now we know.