Environmental Assessment in Building and Construction Goals and Scope Definition as Key to Methodology Choices

Access to tools for environmental assessment is a precondition for identifying and improving the environmental performance of building sector products. With the multitude of parties involved in that sector, also the context within which assessment results are implemented varies. Such variations have to be correctly reflected in the premises under which an assessment is carried out. A wide variety of assessment tools, from simple checklists to Life Cycle Assessment (LCA) approaches, is available. The choice of assessment method has an evident influence on the character and quality of the generated results.

Without confronting the ISO framework for LCA, a large variety of methodology choices can be made by the LCA-practitioner in order to adapt the assessment to his requirements. The application context is to be reflected in the goal and scope definition of the assessment. From that definition, methodology choices are to be made concerning among others allocation procedures and the delimitation of the analysed system. The choice of allocation method has shown significant influence on the generated results, when applying LCA on highly recyclable building materials.

Within this publication, a method for deriving a link from the goal via the scope into the definition of system boundaries, and an economic allocation procedure for reuse and recycling, are proposed. Both are intended to enable a clear link between methodology choices and the goal and scope definition, which was identified as the key point in LCA. The methods presented in this publication do accord with the ISO standards.