When we look at the various material categories coming from raw materials, we have clustered the whole thing here in the materials exhibition according to the very typical material classes of coating concrete, paint, glass, wood. Because in some of these areas, a few examples of materials are picked out.

We start with a material that makes the hearts of a lot of architects jump, I watch it over and over again, the delights of concrete as a material. A good friend, with whom I also do and offer continuing education on the subject of concrete, also talks about his diva, actually describes concrete as a diva, a very, very complex material. Consists of various raw materials.

You could now also say that concrete is not a natural product because it does not occur naturally from the various raw materials combined in this way. Nevertheless, from the point of view of healthy construction, here are a few small aspects that I would like to show you. Which, when you think of concrete, you might not have it right on the note at first, because it doesn't go straight into it.

This starts with more and more research, development and experimentation with how the various compositions, based on the mixture of three substances, can be worked with natural materials here, partly replace the famously scarce sand in some regions with other additives and here is a development that has already implemented this quite successfully, a wood cement concrete that has a high proportion of wood fiber as an additive right here and thanks to this proportion a relatively large amount of gravel, on the one hand, replaces sand. On the other hand, this also makes it possible to create significantly lighter concrete, which is now used very successfully and is often used, for example, in the area of renovations, because during renovations, if you imagine that you have to add a new screed, the corresponding weight issue may even have to strengthen the statics in the worst case.

Ideally, this can be handled quite gallantly with this healthy chipboard because its volumetric weight is significantly lighter. In order to stick with the issue of weight, especially in view of the fact that today, construction is becoming ever faster, it is observed that more and more is also being prefabricated. And the topic of weight becomes correspondingly more relevant, on the one hand, the issue of savings in transport, the lighter the component is.

Concrete is now a rather heavy material. If you look at developments in concrete, you will notice that there has been tremendous progress in recent years when it comes to the weight class of concrete. Of the 2-2.5 tons per cubic meter, they have now reached below eight hundred kilos per cubic meter.

So you can say that concrete as such is becoming significantly lighter, and then the question is again: Linking to the raw materials just mentioned, how do prefabricated plants, for example, manage to develop such lightweight concrete elements today. The whole thing has often forgotten not only transport advantages, but also, of course, from a health point of view.

Does it even go down to assembly that I have such lightweight components much easier to install, whether in interior design, whether on the façade, also that one aspect where you have to keep in mind that I sometimes have to admit when I look at construction sites, I often think to myself that I don't want to be the construction worker in certain construction sites with certain materials. This is also a health aspect, how heavy is a material to handle.

How can you achieve this weight loss? Some time again the link to see what is actually contained in individual components of these materials. One of the developments that make it possible to produce significantly more weight-efficient concrete elements today is to change the reinforcement. Until now, classic reinforced concrete, as the name suggests, the reinforcement, which absorbs the tensile forces, has been made of steel and metal. As a leap in innovation, there are the so-called textile-reinforced new types of concrete, which rely on high-performance textiles instead of steel reinforcement. CFRP, GRP, carbon and due to these very, very thin, you can see the really razor-thin reinforcement mats here in cross section, which can absorb significantly greater tensile forces, manage to push the corresponding cross sections extremely downwards here, the covering of the rust-proof reinforcement can also be correspondingly thin and with this design approach, if you like, composite approach manages to reduce the weights here.

Another strategy is to win the contract. To say I use as lightweight supplements as possible instead of the classic stone, there are more and more additions that are extremely light, although there are now a few really strong wackers on it, it is a very, very light plate. This is a glass foam ballast, which is extremely light precisely because it is produced almost like yeast dough with lots and lots of air bubbles. Nevertheless, it offers very high compressive strength and if you now imagine working with these additives, it is relatively obvious to say that we will make your concrete element lighter.

If you combine the whole thing and say you work with lightweight additives plus textile reinforcement, there are now material qualities that combine the whole thing to the effect that with these combinations of textile reinforcement and lightweight surcharges, you can achieve completely, completely different dimensions, completely different weight classes.

From the point of view of healthy construction, especially as briefly mentioned before, in the case of façade coatings, if you now take the environment as a standard of consideration under the healthy aspect, we once again have the issue of the cycle of resource consumption.

In terms of tonnages, concrete is still one of the weight classes of the most technically used materials in the world after water. Definitely, in developing countries, it is the second most used material here after water.

The lever is correspondingly large here, once with the weight saving just shown, because the weight saving is of course also accompanied by a corresponding saving in material, material efficiency in turn, healthy for the environment, significantly less is consumed.

Another factor that is currently attracting more and more companies to the scene here in the greater Stuttgart area is the so-called R-concrete, recycled concrete, where companies are coming to the funnel that is very certainly also highly interesting in the long term, that the already installed mass that we have produced in Germany in recent decades is so gigantic that it is indeed economically interesting to think of cycles here and to relieve the environment accordingly by recycling demolition material from New recipes are then created in accordance with these conglomerates and the so-called R-concrete, recycled concrete, is then produced from them.

There are approaches that say that in the future, when we rebuild buildings that regard as mines and say everything that is used and installed here, must be able to be returned to circulation in the future. With concrete itself, this is increasingly successful.

First of all, because new recipes are being developed as well as sorting in the separation process using modern technologies, modern sorting systems is becoming ever finer and, accordingly, the topic of R-concrete will certainly keep us very busy in the next few years, there are more and more buildings from year to year which show that this material quality can be used to build and work in a highly functional, highly stable way.