Where has the source data come from – how can I trust it?

The data has been provided by BRE. Over the last decade, BRE has been working closely with industry and trade associations in order to collect primary data on materials. This data has all been independently and impartially assessed using the same methodology, the BRE Environmental Profile Methodology, and the results are therefore comparable. Where data has not been collected from industry, the Ecoinvent database was used as a reference and has been adapted for the UK market.