Viollet-le-Duc and the rational design method Viollet-le-Duc, with his penchant for rational analysis, was the first to articulate a complete theory of the design method. This method owes much to Durand and the further development of its system at the Ecole des Beaux-Arts, an institution which Viollet-le-Duc loved to vilify. However, it was he who laid down the method in a consistent, attractive and very detailed. In fact, his is almost the only theory in this sense, it is not replaced by any other and remains largely intact even in the current architecture. Actually it has adjusted and altered, and most of the architects who use it in their daily work today are unaware of their origin, although it remains one of the most important contributions of Viollet-le-Duc's theory of architecture .
This method of designing a building, described step by step in the history of a house (Paris, 1873), is the intellectual basis to organize and implement the theoretical principles that he and others had set out after him.
The first premise of this design method is that the project of an architect depends not only on the free play of imagination, but a response to customer needs. In other words, the project must be determined by the functional program, which also, in large measure, must be articulated in detail by the client or their representatives.
The program, through the imposition of such limits, challenges architect's imagination and creative impulses channels.
The second factor is usually the choice of location. Overall, the program and the location make the client a partner in the creation of the building. As the architects acknowledge, the involvement of a client in turn inspired inspired the designer. The design method only starts when the customer has made a contribution.
The commitment of the architect usually arrives as a result of a fruitful discussion of the program, but it is unlikely that this initial step can occur without also examine the project site. At this point for the architect to do a thorough analysis of it, preferably in consultation with technical experts. It should be geological evidence to establish to what extent the site can support the building or buildings under consideration, including factors such as determining which parts correspond to the so-called virgin soil, that is, where never before been built, and which have already been filled or built, and soil type (sandy or clay) and the depth of bedrock, because all these factors limit the height and weight of any construction viable. Another factor closely related to the above is the drain and whether or not carried out artificially. Except in a conventional urban lot, we must also take into account the availability of potable water and provision of a sewerage network. Especially in the city, the architect must take into account the legal restrictions imposed by the business community edification, and they include zoning and building types, building height, proximity to the street alignment and stocking density.
Then and only then, can the architect started studying the site in search of the optimal location and orientation for the new building. Factors affecting in that decision are the views from the location, direction of light, prevailing winds, access and the most convenient areas and service routes. After considering all these practical issues can start thinking about the artistic composition of the building or complex of buildings, and the exploitation of the natural conditions of the site. Often the site survey will provide sufficient inspiration or tax sufficient to limit the project has begun to take shape in the architect's mind.
plant development begins with a careful program review. The space for the most outstanding activity should be located and oriented properly. The other activities associated with the program follow a hierarchical order. The most closely linked to the main must be located in premises adjacent to it. The representative functions for a house should have a prominent location, while the service will have a secondary location. The functions that are of different nature should be separated from this group of media space, but have clear and logical access. In other words, the plant begins with a set of adjacencies that need to be adjusted in relation to external exposure to light and views. And then clarified as a composition of shapes defined. Must impose an acceptable range, with dimensions that correspond to plausible sizes and proportions to serve different functions. The dimensions should take into account the thickness of the walls and other structural feature. To be able to work with the composition it is to enter the circulation spaces and access. Before completing the plant should incorporate entrances, doors and windows media.
Start at the plant means that the project is built from the inside out and in terms of functions rather than formal arrangements. This procedure is unlikely to obtain geometric regularity in the whole form or mirror symmetry in the arrangement of spaces unless frequent duplication of functions. Other aspects of the project, especially the structure and the rebels are determined by the plant and are subordinate to it.
The second step of this method is to project the covering of the plant. This presupposes having adequate structural support, but stressed the priority of housing as a determinant of the structure. Viollet-le-Duc recommended a section as a vertical projection of the plant, which show the height each floor of the building, whose number could also be a key factor for the development of an appropriate structure. Along with the plant, that section would help the architect to visualize coverage areas.
Given the large differences between different types of structure available to modern architects, such as type wooden balloon frame, which supported masonry or steel, "the scope and the project budget will likely determine the basic materials and type of structure they imply. For example, is very different if the project is a house private or multi-storey commercial building. So actually create the structure is fundamentally a matter of determining the specifics of a structural type already formulated. For example, the roof of a house with many salient geometric inclinations may require several integrated and carefully calculated to make all the tails of the roof fall to the outside corners. A cover of this type will determine the necessary supports and therefore automatically configure most of the structure.
However, in a larger building, which normally have a formal cohesion is more likely to cover support is established by the span between pillars.
The elevations are the third step in this method. Although they are the most visible externally, hence its importance, "are supposed to develop from a combination of the plant and the structure supporting the deck, even when they are bearing. The holes in the facade must be determined by internal needs and not for any kind of imperative related to external consistency. The size, location and shape of each window should be uniquely functional considerations. Similarly, Entries must be placed where it best fit on the ground, without deference to central themes. Viollet-le-Duc said that the asymmetries and variations of the rebels as a result of the strict response to functional requirements to be considered rational design and bearing, in preference to formal coherence irrational.
The composition of the rebels have much to do with the materials and type of structure previously adopted. In a metal frame building, for example, the design of the elevations can properly be derived from the joint created by the pillars. In contrast, in a factory building with walls bearing joint of the elevations is more a matter of aesthetic preferences that a rational expression of the structure. In this regard Viollet-le-Duc said that as the joint is not structural pillars and pilasters is not an expression of the structure should be avoided because they are irrelevant to the needs of the building.
The decor is appropriate for the architecture, but must come from the treatment of the structure and not a later addition. In many cases, effective solution to a structural problem can be decorative. For example, the pieces of a metal girder can be joined to form an ornamental design that is also structurally efficient. The inherent principle is reflected in examples like the drawings of brick and terra cotta cladding of Louis Sullivan's skyscrapers, and as geometric patterns molded into the concrete pillars of the buildings of Frank Lloyd Wright. This principle of decoration favors the integration of all the ornamental treatment of a building and therefore the recognition of the project as a whole.
Ultimately, a design method established from an ordered series of steps was required to grant the necessary architects to create works not subject to the rules the past and give them the freedom implicit in a theory based on principles rather than conventions, serving also as a basis for generating the international trend that included the so-called Art Nouveau and then the modern movement. This made possible the synthesis of engineering and art that had run Viollet-le-Duc.
Fill Hearn, "Ideas that have shaped buildings", ed. GG.2003
