A building structure doesn't simply exist; once it is built it requires upkeep and materials for repair, just as a plant requires pruning and nutrients. Unfortunately, the maintenance or reuse of a 30-year-old building seems incredibly dull when compared to a flashy new skyscraper.

With an increasing emphasis on 'build nothing', and design for deconstruction, this attitude is slowly beginning to change. Today, Janet and Ellie examine what exactly maintenance involves, and how ideas such as 'material passports' could elevate the building industry; after all, 'one man's trash is another man's treasure'...