Life Cycle Assessment of an Office Building Based on Site-Specific Data

Abstract

Life cycle assessment (LCA) is an established method to assess the various environmental impacts associated with all the stages of a building. The goal of this project was to calculate the environmental releases for a whole office building and investigate the contribution in terms of environmental impact for different parts of the building, as well as the impact from different stages of the life cycle. The construction process was followed up during production and the contractors provided real-time data on the input required in terms of building products, transport, machinery, energy use, etc. The results are presented for five environmental impact categories and, as expected, materials that constitute the main mass of the building and the energy used during operation contribute the largest share of environmental impact. It is usually difficult to evaluate the environmental impact of the materials in technical installations due to the lack of data. However, in this study, the data were provided by the contractors directly involved in the construction and can, therefore, be considered highly reliable. The results show that materials for installations have a significant environmental impact for four of the environmental impact categories studied, which is a noteworthy finding.

Detailed Assessment of Embodied Carbon of HVAC Systems for a New Office Building Based on BIM

“…The resulting GWP due to fabrication are compared to a similar case study in the Swedish context [7]. The two case studies are implemented for the new office building and have a similar LCA scope and boundary conditions.…”

“…In general, there are two types of LCA studies for HVAC systems. The first type of study conducts a comparison between two or more HVAC systems, to identify which system has a smaller environmental impact, or to assess how multiple parameters such as climate, energy mix, and local policies influence the resulting environmental impact [6][7][8]16,32,33]. These studies are not interested in a detailed assessment.…”

“…One of the main purposes of such studies is to provide transparency of the actual impact of HVAC systems and avoid simplifications that can lead to inaccurate and misleading environmental impact calculations. In the context of this research, only four studies [7,[29][30][31] have been found to follow a similar approach and are further discussed in more detail.…”

“…Ylmén et al [7] use a real case study of a new office building in Sweden to perform a detailed post-construction LCA using site-specific data provided by the contractors. This LCA has a similar scope, functional unit, and boundary conditions.…”

“…Furthermore, it has been estimated that embodied carbon in buildings can contribute up to 80% of lifetime GHG emissions for energy efficient building [5].These developments indicate the need to assess the embodied carbon of the whole building. The importance of reducing embodied carbon is underlined in many recent studies [6][7][8][9][10][11] as well as in the most recent World Green Building Council's report "Bringing Embodied Carbon Upfront" [12], which outlines the vision of zero operational and embodied carbon for new buildings by 2050. In the same report, the importance of life cycle assessment (LCA) as a consistent and globally accepted method to assess and communicate environmental impact through the lifecycle of the building is clearly stated and structured according to the lifecycle stages or modules defined in the widely-adopted European standard EN 15978.In new buildings, reduction of operation energy has usually been achieved through better insulation of houses and improved technical systems [13].…”