Summary of rationalism in architecture. Chronology, phases, description of rationalist architecture and differences with organicism.
Rationalism in architecture
The modern avant-garde architectural movement that takes place between the two wars and is fundamentally divided into two large branches, two expressive forms: Rationalism and Organicism (organic architecture) .
Let’s see what the characteristics of both are, also through the works of the most famous authors.
Characteristics of Rationalism
Within this new form of architectural artistic thought there are very strong personalities who bring personal characteristics to art and characterize the latter in an absolutely subjective way.
Among these we find Mies Van Der Roue who creates a temporary exhibition pavilion in Barcelona, which should represent Germany: here he shows the construction principles of rationalism , identifiable in:
- Use of reinforced concrete ;
- Presence of load-bearing structural elements in steel , which free the perimeter retaining wall from its load-bearing function, thus freeing the floor plan. The walls are no longer important for delimiting the interiors of the structure as the support is entrusted to pillars and reinforced concrete;
- Liberation of the facade of the buildings , which opens up to very large glass windows, to ribbon windows;
- Arrangement of spaces in orthogonal terms , that is, surfaces that meet and determine square spaces, so much so that this architecture is associated with Mondrian ‘s neoclassicism .
In modern architecture, therefore, we find this desire to use new instruments, technological and construction processes, associated with new materials such as steel, glass and reinforced concrete . From art nouveau , the experience from which this new architectural experience starts, the material is recovered, but the decorative facing is completely eliminated, which is abolished altogether.
This new architectural language goes to dismantle what is the discourse linked to architectural historicism represented by art nouveau and eclecticism, bringing with it a different language based on functionality and essentiality: the architectural structure must respond to functional requirements, eliminating all the decorative apparatus, which also disturbs the appearance and liveability of the spaces. This discourse started with Adolf Loos, an architect of the late 19th century , who stated that the building had to respond to these criteria.
Rationalist architecture: examples
The first building of rationalist architecture is the Steiner House by Adolf Loos : the shape is a regular parallelepiped, with expressive characteristics that are represented by the use of white plaster and the identification of windows distributed in a functional way to the environment to which they correspond. The distributive freedom takes on a functional role for the environment.
Within the rationalist language , we find differences at an architectural level, depending on the architects considered: at a general level we find an interest in the use of innovative materials and construction techniques that are also new. The new materials are obviously iron, glass and reinforced concrete. Reinforced concrete is made up of a concrete conglomerate (stone aggregate, i.e. gravel and stones, sand and hydraulic binder, i.e. cement): the structure is made solid in this way. The cement for its part holds pressure very well, while the steel reinforcement reacts well to traction.
The synergistic combination of both allows the architectural structure to be supported only by reinforced concrete floors and pillars.
Wooden formwork will be used to give the concrete the desired shape: the concrete agglomerate is left in place until it consolidates. Only then are the wooden slabs removed.
Dom-ino is the modular structure that is used and that supports a building. Thanks to the pillars and floors made of reinforced concrete it is possible to eliminate the supporting walls and therefore free up the floor plan.
Le Corbusier states the fundamental points of rationalist architecture:
- Use of pilotis , or pillars that raise the structure from the ground, making it like a stilt house;
- Freeing the plant from dividing walls ;
- The facade is free for the insertion of ribbon windows;
- The garden roof , or a flat covering on which earth is planted to grow a lawn (thermo-regulating purpose).
The Bauhaus
New school built by Gropius , literally “the house of building”, built in Weimar : from 1919 to 1924, they are forced to dismantle it because the Nazi regime opposes the innovative and revolutionary ideas of the school. The funds are cut and Gropius leaves.
The entire structure is made up of five regular geometric blocks, connected to each other: each block corresponds to a very specific function and all the windows and the facade are determined in relation to this.
There is a section dedicated to laboratories, one to classrooms, one to administrative offices, one to a lecture hall, theatre and canteen, one for student accommodation.
There are no delimited spaces inside and the windows allow a total entry of light. This school is one of the best examples of rationalist architecture: it expresses not only the issues inherent to the new concepts of construction, but also the ethical concept of rationalist architecture, that is, thinking about the student and his education. The student must be trained in all respects and must work well in suitable environments.
Gropius himself, before opening this school, had already combined two study paths, craftsmanship and art, in order to create professional figures who were fully prepared on the skills and capable of producing artifacts of the highest level. What is created in this school will then be put into serial production on the market. Kandinsky and other famous artists of the time taught in this school.
The furniture of the Bauhaus was made by young students: modern design was born right in this school.
F. Lloyd Wright
Frank Lloyd Wright , founder of organic architecture , built his house on the waterfall in Pennsylvania for the Hausmann family . By organic architecture we mean six fundamental principles, defined by Write himself:
- Simplicity , which is achieved by eliminating anything superfluous, including internal dividing walls;
- The houses built must be characterized by as many styles as there are styles of men;
- There must be a harmonious relationship between the building and its surrounding environment : the construction must arise spontaneously from the place where it is located;
- The choice of colors must be in harmony with the environment;
- Enhance the nature of the material , showing which elements are the load-bearing ones and which are the carried ones;
- The house must express a spiritual integrity , those qualities that also belong to man and that make it eternal in time, not susceptible to changes linked to fashion: these values are sincerity, truth, grace.
The house on the waterfall is made of stone and concrete and organically follows the environment, which is itself imitated: the differences in level created by the protrusions of the building imitate the protrusions of the stones.
You enter through a carriage house, and you arrive at the entrance, off-center with respect to the plan. The house is on three levels . The free plan is absolutely used: there are no dividing walls and everything develops around only four pillars, which support the entire structure.
This was quite a challenge at the time, when it was not believed that such a thing could be achieved: the terraces protrude greatly from the building and without the use of resistant materials such as reinforced concrete it would not have been possible to build it.
