11 Nov 2015
Elaine Toogood compares environmental product declarations (EPDs) to food labelling. If only establishing environmental impact was as simple and irrefutable as analysing salt or calorie content.
Comparing environmental product declarations (EPDs) to food labelling is a brilliant analogy, if only establishing environmental impact was as simple and irrefutable as analysing salt or calorie content.
Instead there is a complex web of data collection necessary, at every stage of each product's manufacture, and all of its constituent parts. Another difference is that EPDs cover different stages of the product's lifecycle: cradle to gate, to site through operation, then demolition and end of life.
Comparison between EPDs needs to ensure the same stages are being compared. Even though there is a European standard to help ensure consistency between different products this has yet to be fully achieved. And even though there is consistency in how an EPD for one product is calculated, different experts will arrive at different results as there are still many assumptions on input data. This is a particular challenge for material producers and users of EPDs.
The concrete industry recognises this and is progressing with production of information to make it both usable, comparable and tp provide a workable model to evolve over time for BIM. Most, but not all products, require 3D data as well as information. 3D information for some products is embedded in software. Individual manufacturers have already been providing 3D objects (dimensional data) and information into various BIM object libraries. The industry is working within product sectors, to develop agreed formats and templates for information required for EPDs, which will include ECO2 data.
Cement has already published a generic EPD. EPDs for concrete products including ready-mixed concrete are currently being developed. The time frame for publishing EPD information is early 2016 and for product data templates for BIM, is likely to be middle of 2016. This is, however, an iterative process and further work will be necessary for common formatting across product industry sectors to enable project teams and their BIM tools to work more efficiently.
I suspect that there will be a steep learning curve for operators of BIM to understand and input data once more of it has been established. This exercise has a high risk of producing misleading results, particularly with the use of concrete, since it comes in multiple variations of types with a wide range of associated impacts.Then of course, there is the necessity to keep this data current which, following the current trajectory of improvement in concrete’s environmental credentials, will be only mean even lower impacts.
So in the future EPDs, if used correctly, will help inform the design and construction of our buildings and structures and help lower impacts such as carbon emissions, but at the same time we shouldn’t lose sight of the overall whole life targets and in the case of carbon, the potential through material selection for reducing operational CO2. After all, looking at food labels and counting calories can help us be healthier, but we all know the importance of exercise as well.