Bei der Beurteilung von Sichtbetonflächen kommt es oft zu Meinungsverschiedenheiten zwischen Bauherren, für die Gestaltung zuständigen Architekten und bauausführendem Unternehmen. Das zeigt zumindest die Erfahrung der DBV-Bauberatung. Ein wesentlicher Grund für diese Meinungsverschiedenheiten liegt in der (oft unbewussten) Festlegung des Betrachtungsabstands von Sichtbetonflächen. Denn: Das grundlegende Beurteilungskriterium von Sichtbetonflächen ist immer der Gesamteindruck aus dem angemessenen Betrachtungsabstand, der sich bei üblicher Nutzung ergibt. Der Beitrag enthält Hinweise zur Festlegung des „richtigen“ Betrachtungsabstand von Sichtbetonflächen bei üblicher Nutzung.
Assess exposed concrete: Explanations on the viewing distance and usual use
When it comes to assessing exposed concrete surfaces, there are often differences of opinion between clients, architects responsible for the design and the company carrying out the construction. At least that is the experience of the German Concrete and Construction Engineering Association (DBV) consultancy. A major reason for these disagreements is the (often unconscious) determination of the viewing distance of exposed concrete surfaces. Because: The fundamental assessment criterion of exposed concrete surfaces is always the overall impression from the appropriate viewing distance that results from normal use. It is the task of the person assessing fair-faced concrete to take into account or at least imagine the subsequent normal use and the normal lighting conditions during use and from this to determine the appropriate viewing distance as the basic assessment criterion for fair-faced concrete surfaces or fair-faced concrete components. This requires a lot of experience. It is also in the nature of things that the approach described above is also always subjective. This is because every observer has different often unconscious ideas about the usual use and thus about the appropriate viewing distance and the usual lighting conditions. The assessment of fair-faced concrete should therefore, if possible, always be carried out by neutral, outside fair-faced concrete experts and not by those directly involved in the construction. The contribution contains information on how to determine the „correct“ viewing distance of fair-faced concrete surfaces for normal use.