Almost 130 years and many building styles later, it’s hard to imagine construction without steel, especially modern commercial, multi-story, and industrial construction. The demands are stricter now; construction is no longer determined by function and aesthetics alone, but by sustainability, too. Architects, engineers, and above all, manufacturers of building materials have a huge responsibility.
Saving on resources
Steel structural elements can meet all those requirements. Demand for heat-insulated sandwich elements and trapezoidal profiles and curtain walls such as Siding Plus is rising in modern commercial and industrial construction. Last but not least, steel structures are easy to dismantle and up to 100-percent recyclable.
But that isn’t even necessary in many cases because high-quality corrosion protection keeps the building durable, while carbon steel available in every conceivable color and design guarantees it will look good for a long time. “We offer a very diverse range of design options in this area,” says Axel Pohl, Head of Sales, End-User-Industries at thyssenkrupp. “That goes for color, feel, texture, and design.”
thyssenkrupp offers customers carbon steel with paint or film coatings under the pladur® product name. Whereas the focus of the painted products is on color, luster, and texture, the film-coated products primarily aim for decorative impressions. “With our newly developed pladur® Impress line, we are now able to offer customers a previously unprecedented variety of designs.”
The advantage here is that the process no longer mandates a minimum order size in the thousands of meters. “As a result, we can now offer a broad customer base not only large batch sizes, but also smaller quantities tailored to the needs of the individual customer and the construction project.”
One of those customers is Hoesch Bausysteme. The former component division of thyssenkrupp was sold to Kingspan Holdings of Ireland in 2012. “Our biggest business area is undoubtedly the production of sandwich panels,” says Ulrich Reidenbach, Managing Director Sales at Hoesch Bausysteme. “But we are trying to cover building envelopes as completely as possible. As a result, we deal with insulations and even manufacture our own, for example, our new QuadCoreTM insulation core, and we offer window and dome light systems.”
Apart from sandwich elements, the most common elements in steel construction are trapezoidal profiles and metal curtain walls, straight-line components that can be installed diagonally, horizontally, and vertically as ventilated curtain walls. “Sidings are easy to mount and offer a wide variety of design possibilities,” says Reidenbach. One important quality feature of steel facades is their resistance to corrosion and UV radiation.
The material also has to be very good to work with, because the paint is applied when the metal is flat, and then formed afterwards. This means the coating has to be formable and aesthetically pleasing, as well as resistant to wear. “And that’s where we’re needed again,” says Pohl, “because customers like Hoesch take our semi-finished product and make their end product, which then appears on facades.”
Clarifying the benefits
A lot of preparatory work is required before that point is reached. Architects and building contractors have to know the benefits of steel facades long before planning a building. Sandwich panels, for example, arrive at the construction site prefabricated. This minimizes errors that might occur during installation. It also makes it possible to build things in a very short time. Sandwich panels have a high load bearing capacity and very good insulating properties, while complying with fire prevention requirements. In addition to architecture consulting, thyssenkrupp Steel offers planners and architects a special product folder that is still expanding and includes parts from the pladur® portfolio. The collection contains high-quality original samples and provides data on characteristics that make the materials especially useful for industrial and multi-story buildings.
Studying steel facades
Professor Helmut Hachul saw the potential at Dortmund University of Applied Sciences years ago. In 2006 he took over the Chair of Metal Construction, sponsored by thyssenkrupp, and in this capacity established a master’s program in Metal Building Envelopes. He was especially excited by high-tech sheet metal. “A material that can be formed in many different ways, thereby gaining stability,” says Hachul. “It allows components to have thinner dimensions and saves resources. And it’s now possible to shape it in diverse ways.”
Steel facades, and sandwich elements in particular, are hugely popular on the market. For students in Dortmund, this means that surfaces not only have to be shaped, but made more efficient as well. For example, there is research on integrating photovoltaics and solar thermal energy into the outer shell. “When raw materials run out, we’ll need buildings that supply their own energy,” says Hachul. In the area of surfaces, today’s planners can select steel facades that radiate a certain atmosphere.
“Architecture should serve people. I emphasize this because industrial buildings constitute large-scale architecture with tall facades that can be seen a long way off.” There is a need for buildings that coexist in harmony with their environment. “My goal is to teach an approach to architecture that considers the residents who have to live with these buildings.”
Three questions for Prof. Dr. Helmut Hachul
You teach and do research on metal building envelopes. Why?
As an architect, I’m fascinated by steel structures. Steel is extremely versatile. We can use it to do outstanding work in the area of lightweight construction and save resources in the process. I’m bothered by the fact that the focus has long been on cost efficiency rather than design. This is changing, thanks in part to companies such as thyssenkrupp and, of course, our graduates.
What edge do steel facades have over other materials?
They are extremely stable, lightweight, versatile, and resistant. The design possibilities are immense. But as with all construction methods, the design suffers when money is the main consideration. Buildings are the most sustainable things we build. They stand for an unbelievably long time in public spaces. The half-life of autos is much lower.
What will change for architects in the future?
Interdisciplinarity will increase. With regard to steel, we will plan buildings in the future with chemists, mechatronics engineers, and electrical engineers. There will be a lot of developments with coatings. Apart from that, cost-effectiveness, energy efficiency, and customization will get even more important, both in industrial construction and in urban and private buildings.
Three questions for Ulrich Reidenbach, Hoesch Bausysteme
What are the major challenges in the building trade?
Definitely digitization. Both in the building industry and the supply industry. Furthermore, ever-expanding requirements for thermal insulation and fire protection necessitate constant research and development work. A prime example of this is QuadCore, a newly developed foam system that currently offers the best insulating properties.
What are the challenges facing your industry?
We often have lead times of less than three weeks. Short-term orders are not at all uncommon among our customers. For that reason, it is both our aspiration and a quality feature of our service to be able to offer short turnaround times and flexibility when delivering our facade elements, as well as suitable accessories for daylighting solutions, such as skylights, windows, and gutter systems.
Your company once belonged to thyssenkrupp. How about now?
When thyssenkrupp decided to sell its Business Area for building components, the entire company was purchased in 2012 by Holding Kingspan, an Irish company. The imported and internationally respected name Hoesch Bausysteme was retained. While we do have a new parent company, we nevertheless function as an independent trade mark.