- identify and evaluate options for measuring the future recyclability of construction products;
- advise how construction clients might set requirements for recyclability in their procurement of projects; and
- advise how data on the recyclability of common building products might most effectively be included in a
A key requirement of the indicator is to be able to quantify the relative benefits of different classes of recovery, i.e. downcycling, recycling and reuse (compared to landfill1), for both construction products and projects. At the project level, it also needs to be able to differentiate standard, good and best practice solutions as a yardstick for improvement by project teams; though to do this it has to be assumed that the building will be deconstructed in the way that it has been designed to be.
The study initially looked at six options, but Ecological Footprints2 and a relative scale were quickly discounted due to, respectively, a lack of data and the potential lack of industry buy-in to a non-scientifically based indicator. The four remaining indicators; mass, value, Ecopoints3 and embodied carbon dioxide were assessed in more detail. The analysis looked at the fundamental characteristics of the indicators and data availability, and calculated the recyclability of bricks, steel, concrete and carpet assuming different methods of recovery. At this stage, an extensive consultation was undertaken with relevant stakeholders from industry, Government and the Not for Profit sector. There was a range of opinion, and although it was broadly agreed that recyclability was an important issue, and that this was an area that required guidance, opinion was divided over the need for an indicator. The majority of organisations supported an indicator but the Construction Products Association felt that the life-cycle assessment approach taken by BRE’s Green Guide to Specification should be the primary or only indicator used. It was agreed though that if the indicator were developed in such a way as to be compatible with the Green Guide, this would make it more useful.
The metric of recyclability which gained widest support is based on the efficiency with which the embodied carbon dioxide of construction products is conserved in the recovery process. Although it would not be the easiest to implement, there is already an ever growing body of data in this area and it is a scientifically robust indicator that is able to differentiate between different classes of material recovery and also be used on both short and long lifespan products.