Potenzialità espressive del legno lamellare: durevolezza ed ecocompatibilità per il disegno estetico dell'architettura. Expressive potential of GLULAM: durability and sustainability for architectural aesthetic design.

The design process is characterized by multiple steps involved to bring about a result that expresses material and immaterial values, which are larger than the mere sum of actions . Architecture is not only the result of an operation sequence that sees before the project, then the verification of the conditions that determine the feasibility and finally the realization, but identifies an higher value result from sensory experiences that involve different aspects of our living in a three dimensional space. The disciplines of architecture know that when you have to decide a material that will help to create a building, you should not only consider its technological performance, even if this aspect is of fundamental importance for the structural behavior of a building, but there are some other properties that has to be considered. They have a value on the aesthetic and expressive capacity of the material. This could be determined by the color rather than by the relationship in a more complex environment of other materials used; from perceptual experience that it can offer, rather than by the easy availability in the place where you want to build. These and other values must be well known to architects, because the materials do not only have the task of making performance, but also non-physical and non-visible features, justifying the choice that becomes appropriate if done in relation to the constructive solution designed and the specific problem to be solved. For what said above, we know that the choice of materials involves choices regarding both the technological quality components in the physical and mechanical properties, both also aesthetic capacities that can be translated in the surface characteristics of the material. The quality of materials for architecture is apparent in compatibility, workability and in the availability , as well as in durability and - now more and with greater conviction - in ecological sustainability. While we may know characteristics of the behavior of a material under a specific stresses, is not as immediate to recognize the path that leads to identify which and how many are the expressive potential that the use of that material can generate, most of all if it placed in relation to other elements that can participate to degenerate or to give an aesthetic balance. There are, in fact, numerous aspects which contribute to give aesthetic quality to a material : the color, the ability to reflect or absorb light, the type of processing which determines the roughness or smoothness of the surface, the possibility of defining a geometric composition, correspondence to the will and aesthetic perception of the project and much more. Many times there are even correspondences between the mechanical function and the recognition of an aesthetic will: the concept of durability is combined in some cases even with the ability to perpetrate the beauty, thus a choice of aesthetic can coincide with a time resistance capabilities. Even the character of eco-sustainability is becoming more and more a value that can promote the choice of some materials as platform of those expressive and ethical aspects, that rightly should be contained in a work of architecture. Referring to the action of designing, which includes the phase of the implementation of an idea in construction material, the choice of a material consists in multiple assessments that are intended to offer quality inextricably linked to the building you intend to accomplish. In this operation, the materials must be identified evaluating them in the broader spectrum of qualities and values, especially when then these choices have to be made compatible with environmental sustainability. The aesthetic choice is reinforced in positive terms by detailed consideration of the consequences on the ecosystem that the extraction, application, processing, transportation and the manufacture of a specific building material may have on the health of the population and, in general,on the entire balance of a specific habitat. This article talks about the expressive value of the glulam as building material that has lots of the mechanical performances and qualities compatibles with the most requirements necessary to build a prestigious architecture, both from an aesthetic that an ethic perspective. The good examples about the capability of glulam to become a construction material of high level are demonstrated with some works of important architects as the australian Glenn Murcutt and the canadians Patkau Architects, from Vancouver in British Columbia.