Somewhat impractical, and lacking any real experience in building, I begun studying Architecture in Delft in 1962. I was skilled in drawing and painting, loved paper, ink, pencils and paint. The unruliness of materials with which I had drawn and painted was a continuous challenge to overcome. It was only after many years in Delft that I was able to grasp some understanding of materials. A lasting impression on me was made through the practice of metalworking and welding and through the early studies of wood, where we had to transform a timber block into a piece of art. This was in fact a crash course in material science, even though our efforts, as I later found out, became firewood for our teacher's open fire. Until this day, 50 years later, I am still benefitting from these exercises. Craft, the taste of making, discovering the limitations of materials and the great admiration for craftsmen are all indebted to my experiences at Delft. Since graduating, I have continued to fill the gaps in my knowledge of materials through attending metal, tile and concrete courses. The fascination for the materials themselves, as well as the interaction between them, their coherence in a building structure, is now more alive than ever.

The computer had not yet entered the world of building when, in 1968, I travelled with several students and professor Bakema, to visit Frei Otto at his studio in Berlin. He had just finished the design for the tent-like roof for the stadium in Munich. It was impossible to calculate how much the main tension cable would sag under the weight of the roof combined with additional snow load. Varying inputs from the brightest engineers in the world gave results from “flat on the ground” to 2 cm maximum. Frei Otto had only tested a small model with imposed scale loads and from there concluded that it was quite all right. Quite remarkably, in reality the roof best matched the expectations that had been predicted in the model! The prototype followed the same laws of gravity and material!

At the end of the sixties, after my graduation, I went to study for a further year with Louis Kahn and Robert le Ricolais in America. Three afternoons a week Kahn held his ‘studio’ with the almost ever-present Le Ricolais as a fellow teacher. Le Ricolais, ‘the father of space structures’, was an extraordinary French engineer, autonomous in his way of thinking. Kahn and Le Ricolais had great respect for each other and enjoyed each other's thoughts and responses. Kahn was continuously working on a greater understanding of materials. In the beginning of his career this involved natural stone of course, then later on concrete and bricks (“what does a brick want to be....”), wood, mostly as a surface material, and in 1950 the sparse use of steel. Much later he ‘rediscovered’ the enormous potential of steel and it came back, albeit on small scale, into his building designs. For Le Ricolais however, steel was his first material of choice! In his laboratory where I was able to experiment for a year, we built models and competed in bridging 60 cm spans as efficiently as possible. The loading to dead weight ratio of the structure rose to a factor 60!

We did tests with bubble shapes in small spatial wire structures and made the automorphism visible: the cubic bubble within the cubic wire model. In 1969 we made models for a Rapid Transit System running from Boston to Washington. It was 30 meters above the ground and travelled at speeds of up to 300 km/h as it had to compete with the aeroplane (including airport waiting times). We developed an ‘automorphic-tube’ through which a train raced (electromagnetically!), suspended from cables which slid over the supports, enabling it to benefit from the stiffness in the tube of the subsequent span. Later a helium filled closed tube was introduced to reduce air resistance. We performed scaled loading tests (like Frei Otto) and based on the results we stretched the span between supports from 60 to 90 metres, all under the nonconformist supervision of Le Ricolais: a true prototype laboratory at its best. What a fantastic manner in which to test and practice with one's own hands, the juncture between mechanics and calculation. The sense and understanding of materials, with all their unruly quirks is of continued educational value to me.

In 1992 when I received an assignment to design a cardboard theatre in Apeldoorn's ‘paper-city’ to celebrate its 1200th year, the prototype-lab-sense came strongly back to life. The amazing properties of corrugated cardboard led to a theatre for 200 people that weighed less than 1500 kg, which was protected from being blown away by a tent canvas that secured the structure to the ground with pegs. The entry ticket was an easy to assemble cardboard chair which you could take home after the show. Despite moisture from the air creeping into the cardboard it just managed to survive the required 6 weeks...

If anything has become clear to me in my long and fulfilled career as an architect, it's that building, for architects the designing and developing of buildings, cannot be seen as separate from matter. There is a need and obligation to develop an understanding of materials, which is endless. Computer technology forms a barrier between thinking and making. With traditional drawing methods, there is still a material bond between the graphite and the paper. Computer technologies and modern rendering capabilities raise this barrier further. Of all our senses, only the visual is triggered.

But with matter there is more. Feeling, smelling, hearing and even tasting forms an unbreakable bond with the visual. The coherence, mutual exchange and respect for matter in it's incredible diversity keeps on being a part of our existence.

Also in new materials, new production techniques, like 3D-printing, there is much to discover.

In this book it is wonderful to see how the Delft Prototype laboratory, founded by Mick Eekhout in 1995, is practising with a diverse range of materials, how materials compliment one another and searching for the boundaries of the prototype and how this is becoming part of the DNA of upcoming architects. In that DNA materials interconnect with cerebral design activity. Thus preventing the visual ‘rendering’ being disconnected from what we ultimately must understand; real materials, gravity and daylight. The Delft Prototype Laboratory is an extremely valuable place.

Hans Ruijssenaars