Estudio del impacto ambiental de la madera como material de construcción de viviendas plurifamiliares de varias plantas

Abstract

Timber is perceived as a sustainable building material by its nature. In recent years, the use oftimber, have been promoted in multiple presentations and a variety of products for the construction of buildings. This trend may create demand, exploitation, processing and increased use oftimber that requires an objective assessment of environmental impacto This could lead, to avoid making mistakes that could reduce the sustainability ofthis material. Consequentiy, it has been proposed to study the environmental im pact that m ay res ult in the use of wood taking into account variables and indicators to make a quantitative assessment ofthe magnitude of impact in the case ofthe construction of multistory residential buildings (VPVP in spanish acronym) in Europe. To develop the studywere selecled 4 impacl variables: lhe relalionship between lhe demand for tim ber and the resource availability in tim e, lhe impact on carbon dioxide em issions , the im pact of em bodied energy, and the amount ofwood used in construction. The first variable is studied bya review ofwood produced in Europe and the different destinations that such production has, in order to determ ine how m uch of the wood produced is intended to build VPVP, and approach the diagnosis ofpotential conflicts in availability of this resource overtime. This studywas done with projections for scenarios in the years 2015 and 2050. The im pact of C02 em issions is studied through the indicator of emissions per unit of construction area expressed in kgC02/m2. It is a detailed study of one m2 offacade built with wood where are considered the emissions from wood waste from untapped cutting processes and felled trees, the wood processing in different products and emissions from fuel or energy sources used in the processing of wood. In addition, references were taken from various sources of information about C02 emissions and em bodied energy in the production of different presentations of timber and wood products normally used in the construction ofVPVP. After characterizing the impact variables and their indicators, we proceeded to apply them to selected cases of study. We compared the impact of various building elements and scenarios. VPVP buildings were developed constituted of various combinations of these building elements in order to approach the most efficient combinations. Finally, we compared the indicators obtained in the study of cases with a case of VPVP of conventional cons truction . Regarding the first variable, we can say that the patterns of production and cons um ption of wood in Europe tend to be sustainable . As for the second variable, it was observed that the impact due to the wood processing depends mainly on the amount ofwaste generated, the use to be given to these residues and the level of process ing required by each product. As for the third variable was concluded that to minimize the impact of embodied energy would be required the use of natural and renewable sources of energy. The construction of composite structures using timber panels combined with natural wood trusses is an intermediate option in values for impact. In terms of the final variable, if the construction of wooden VPVP comes to occupy 30% of total VPVP built in Europe in 2050 may be required one third of all wood demanded by the building industry.