Comparison between the environmental performance of buildings made of reinforced concrete and timber

In order to reduce the environmental impact of the construction industry, the case of natural material (such as timber) is pursued. However, is the use of low-impact materials sufficient to decrease the overall environmental impact of a building? The answer is not trivial, because there are many parameters that affect sustainability, in addition to the unitary environmental impact of the building materials. Through this article, an evaluation of the total CO2 emission in buildings made of reinforced concrete and CLT panels is carried out. The entire life cycle (LCA) of the materials is considered, as well as the CO2 emissions derived from heating and chilling. The relationship between CO2 emissions and building height is also taken into account along with weather conditions. The structures and envelopes of a three - storey family house and of a multi-storey residential building are designed from a structural and thermal point of view, respectively. In order to consider the climatic effects, three locations with very different weather conditions are assumed (i.e. Catania, Turin, Oslo). The carbon footprint of three different structures is considered, namely RC frame made with cast-in-situ structural elements, precast RC panels and timber CLT structure. The quantification of the carbon footprint allows to notice how the overall structural and thermal performances, including the thermal mass, affect the environment performance.