Methodology for evaluating the embedded GHG emissions in the stock of constructed buildings
Climate change, embedded GHG emissions, life cycle assessment, built buildings, as-is BIM
The construction of buildings is a relevant part in the emission of greenhouse gases (GHG), but there are lacks of informations regarding the GHG emissions embedded in the processes and their constructive elements. The general objective of this research is to analyze the impact of climate change in buildings through the LCA methodology. Its specific objectives are (i) to assess the LCA support tools for the Brazilian context; (ii) to compare the applicability of different national databases; and (iii) to systematize an LCA methodology for built buildings. The research method is organized in six steps. Initially, (i) the study area is determined as stage 01 of the Northwest Sector, in the Federal District, and then (ii) the building typologies for the analysis are determined, which in this study are three typologies with different floor plan projection areas (square floor plan, 1.024m2; rectangular floor plan, 1. 000m2; and rectangular plan 1.500m2) and then, it is proposed the (iii) survey of the characteristics of the typologies, (iv) the extraction and organization of the data obtained in the survey, to (v) perform the LCA of the analyzed typologies and, finally, (vi) the interpretation of the results obtained in the LCA to communicate them. As a result, it was observed the lack of knowledge and information about the environmental impact related to climate change on built buildings in the Brazilian context from the evaluation of some cities' climate mitigation plans. Another point observed was the existence of different tools to support the evaluation of GHG emissions in buildings sector in the Brazilian context, but there is not yet a single consolidated platform for use. Typology 1 (23 units) obtained as a result of the LCA a total of 2.65 kgCO2eq./m2.a, typology 2 (51 units) obtained 3.13 kgCO2eq./m2.a and typology 3 (11 units) obtained 4.08 kgCO2eq./m2.a, totaling 265.46 kgCO2 eq./m2.a coming from the residential buildings of the stage 01 of the Northwest Sector-DF, considering a lifetime of 50 years. Finally, it is considered that architectures that deliberate the use of materials with greater rationality can also indicate buildings with lower impact related to GHG incorporated emission.