Green envelopes applied in buildings: benefits and techniques

Abstract

The use of vegetation integrated to architecture has been highlighted in recent years, representing a strategy to increase the green in the cities, exploring urban supports still undervalued as places of growth of vegetation: this is the case of walls and roofs of buildings. In this way, green envelopes may be defined as closures, coatings or construction elements alternative to conventional ones, which has the vegetation as the main component, together with other layers or supports for its fixation or development. The objective of this article is to carry out a bibliographic survey of information about the benefits and the main techniques of execution of living roofs and vertical gardens. In general, both living roofs and vertical gardens can be classified as extensive or intensive, depending on the form of implementation and the degree of difficulty of execution and the need for maintenance. Its use requires planning and technical knowledge, in order to determine which system is most appropriate, which is the execution and maintenance care, and which species are most appropriate to the local climate. The main advantages for the cities are the reduction in the temperature of the air, with minimization of the phenomenon of the heat island; humidification, and have an interesting visual effect. At the scale of the building, the vegetated envelopes can contribute significantly to the thermal comfort and, consequently, to the reduction in the energy consumption for air conditioning of the spaces, since they act as thermal insulation, elements of shadowing or qualifying the natural ventilation by evaporative cooling.