the life cycle performance of sustainable renovation concepts

Appendix F provides more detailed information about the factors that are taken intoconsideration by executing the Greencalc assessment of a building.3.5 LIFE CYCLE ASSESSMENTThree of the four evaluated models in the previous paragraph take environmental impactinto account. However, only Greencalc uses a life cycle assessment to determine the totalenvironmental impact of a building. For a sustainable renovation concept, the life cycleenvironmental impact is the best indicator, because the life cycle approach integrates allfactors with an impact on the environment. The life cycle approach provides a comprisingand comparable score for the environmental impact. Therefore, this paragraph shows aliterature review of the life cycle assessment (LCA) principal. Several definitions of lifecycle assessment are described. The interpretation of a life cycle assessment in thisresearch is based on the different definitions that are elaborated below. Also, theadvantages and disadvantages of a life cycle assessment are described. Informationabout the history and origination of the LCA principle is presented in appendix G.DEFINITIONS OF LCASAICIn the report „Life Cycle Assessment: Principles and Practice‟, SAIC (ScientificApplications International Corporation) provides information about a LCA withoutproviding a clear definition (SAIC, 2006).According to SAIC, life cycle assessment is a „cradle to grave‟ approach for assessingindustrial systems. Cradle to grave begins with the gathering of raw materials from theearth to create the product and ends at the point when all materials are returned to theearth. The characteristics of a LCA as stated by SAIC are listed below:- Evaluates all stages of a product‟s life.- Enables the cumulative environmental impactsin these stages.- Provides a comprehensive view of theenvironmental aspects of a product, processor service.- Can help decision-makers for making acomparison between alternatives on the fieldof environmental impact.FIGURE 19-LIFE CYCLE STAGES (SOURCE: EPA)Figure 19 illustrates the possible life cycle stages that can be considered in a LCA and thetypical inputs/outputs measured.SAIC states that the LCA process is a systematic, phased approach and consists of fourcomponents: goal definition and scoping, inventory analysis, impact assessment, andinterpretationFINKBEINERFinkbeiner et al. (2006) describe the new international standards for Life CycleAssessment in ISO 14040 & ISO 14044. According to these standards the followingprinciples are characteristics for a life cycle assessment.- LCA considers the entire life cycle of a product. The phases of the entire life cycle are:raw material extraction, energy and material production, manufacturing, use, end oflife treatment, and final disposal.- LCA addresses the environmental aspects and impacts of a product system. Aspectson the field of economic and social aspects are outside the scope of an LCA.38