This Report gives the results of a BRE study conducted in 2006 to update weightings for a range of environmental issues first established in 1999. An international panel of 10 experts was set up to judge the importance of 13 parameters and their individual responses have been aggregated to create a single set of weightings. The Report also explains how the weightings are applied to BRE's tools for assessing the environmental impact of construction products.
- describes the methodology,
- analyses the statistical techniques employed and the statistical robustness of the weightings obtained, and
- explains how the weightings contribute to the Environmental Profiles methodology for measuring the environmental performance of construction products.
The weightings exercise
- The participants
- What environmental impacts were weighted?
- The data collection process
- The questionnaire
- Subject response
- Level of expertise
- Reliability analysis
- Analysing the data
- Sensitivity analysis
- 1999 and 2006 weightings compared
- How are the weightings used?
Annex 1: The Expert Panel
Annex 2: Extracts from the BRE online questionnaire
Annex 3: Expert responses
Annex 4: Non-expert responses
Annex 5: Reliability analysis of expert responses
IP4/07 (8 pages) is a shorter version of this report.