From vernacular to sustainable contemporary architecture: Urban green and patios

Abstract

In human-inhabited spaces, the use of vegetation has always had multiple functions, from symbolic, aesthetic or ornamental to production and regulation of the microclimate. The integration of greenery with the constructed spaces is of particular importance today, especially as a valid solution to environmental discomfort and the pollution load of urban spaces. A deciduous shrub reflects and absorbs in the summer a quantity of radiation that is proportional to its hourly and seasonal variations, while in reverse it transmits most of the incident radiation. The leaves chase the sun by tilting and orientating themselves to optimize the absorbed radiation instant by instant. The effect towards internal space and protection from direct radiation, a high level of ventilation between the leaves and building envelope and a percentage of transmitted radiation (mainly diffuse) that guarantees good lighting performance, with a quality of dynamic light that would be difficult and expensive to get with artificial devices. In fact, if this type of phototropic regulation implemented by the foliate mantle of the vegetation is compared to more or less sophisticated systems of dynamic regulation implemented with different modulators (mechanical like the diaphragms of Jean Nouvel in the Institut du Monde Arabe, physical-chemical like the transparent photosensitive materials), one could understand how important it is to develop models and technical systems that hybridize the logic of natural systems with those of technical systems. The sustainable approach recalls the importance of this hybridization process, that is, to reactively use all the renewable resources of nature, also revaluating the environmental characteristics of past solutions and recognizing that they have contributed.