The industry shows featured presentations on the material’s strengths in terms of its environmental footprint as well as thoughts on its weaknesses in terms of image
“The Future with Natural Stone“ was the title of the congress at Stone+tec, which took place in Nuremberg from June 22-25, 2022. For the first time, such an exchange of ideas with presentations by experts and architects was part of the industry show, and the title immediately gave the direction of thinking: “Natural stone is THE building material of the future“ is the motto in paraphrased form because sustainability will be the big topic also in architecture.
Herman Graser, President of the German Natural Stone Association (DNV), provided figures for this in his opening statement: 40% of the climate gas emissions caused by a building in its entire useful life are already caused during construction – this figure can consequently be decisively reduced by selecting sustainable building materials.
Graser concluded, “If you look at a building over its life cycle, we have the most environmentally friendly material in natural stone.”
This statement was echoed by Ansgar Schulz, professor at the Technical University of Dresden and member of the Schulz und Architekten office in Leipzig. He pointed out the commonly false image of stone as a building material: “Building with natural stone is high-tech building,“ he said. As an example, he presented, among other things, a 7-story residential building at 62 rue Oberkampf in Paris, where the facade is made of small solid stone blocks with a load-bearing function (see link below).
“There’s a lot of future in massive building with natural stone,“ he predicted, adding, “Architecture, in general, will have to deal more with natural stone in the future.“
The previous speaker Philipp Hofmann, managing director at the company Hofmann Fassaden, had expressed similar views. In a perforce ride through the company’s current projects, he showed what possibilities lie in the combination of stone with modern fabrication as well as with modern construction such as pre-tension.
About sustainable construction, he called for “architects to choose materials a core theme of their work again,” pointing out that calculations of a building’s ecological footprint often omit those CO2 emissions that are due, for example, to elaborate structural engineering.
Landscape architect Franz Reschke also pleaded for a fresh look at and evaluation of natural stone – but he came to this conclusion from a completely different direction: for him, the strengths of the material for parks and paths in the city lie in its natural appearance and the patina that aging stone accumulates. He wanted “stone as a commonplace in planning, without the material immediately becoming trivial.“
One of his thoughts here was to create stone seating walls instead of the usual seating furniture, which could also be used to define spaces for use. However, he immediately drew limits to the idea again: “We are currently trying to get away from the idea that natural stone always has to be the thick block.“
Stone, then, also as a material for elegant designs, to put it in other words.
René Pier, president at the Landesverband der Innenarchitekten in Baden-Württemberg, was also concerned with this idea: He wanted “a new aesthetic“ in the use of natural stone. As for sustainability, his work follows the idea of reusing the material: he described a villa in Egypt where travertine was removed from a facade and reused in the kitchen as a countertop and splashback on the wall.
Provocatively for the industrial companies, he wished for “machines to recover natural stone from existing buildings, instead of them taking it from the quarry.“
With this, he addressed the currently much-discussed “urban mining.” Kathrin Quante of the German Sustainable Building Council (DGNB) also dealt with it: in this process the city becomes a source of the building materials it needs to sustain itself. Ancient examples of this are the paving stones that were already reused by the ancient Romans.
In this context, Hermann Graser of the Natural Stone Association pointed out that the existing building codes would have to become “conversion codes“ in the future, and introduced another aspect: He pleaded for buildings to be designed for as long service life as possible in order, from a sustainability point of view, to stretch the unavoidable emissions during construction mathematically at least over as long a period as possible.
The entire construction industry is currently in a state of upheaval, as could be seen from the lectures, and so there were occasional quick excursions into philosophy – repeatedly the speakers devoted themselves to the topic of the day. Interior designer René Pier put it into flowery words: “Natural stone is eternity experienced,“ he said, alluding to the fact that the material carries millions of years in it.
Architect Ansgar Schulz said, “natural stone is timeless because it is sensual“. He meant that the viewers of a stone architecture like to pause and linger to also visualize the details of the building.
This sensuality also includes the well-known phenomenon that could be experienced during the presentations at the fair: everyone touches and feels the surfaces of the stones, and no one can say what they hope to feel there.
(25.07.2022, USA: 07.25.2022)