Products and materials that perform the same function may have different production processes and therefore different environmental impacts. For example, the CO2e impact of concrete can vary from 70kgCO2e/m3 to 1000kgCO2e/m3 depending on the recipe and the production process.
At the early stages of designing a building you may not know exactly which product will be used, so estimating the impact will be difficult.
To help with this IGBC commissioned Cambridge Architectural Research (CAR), a team of LCA specialists, to review the Irish markets for common building materials such as concrete, brick and steel to understand the carbon emissions involved in the production processes that create the materials. CAR researched each market and identified the environmental data available for each one. From this, they developed weighted averages for the carbon impact of each market and produced a report available here.
We followed that up with another review by Circular Ecology of more commonly used materials (concrete blocks, insulation materials, slate, stone, windows and doors, plasterboard, and flooring).
All of the results have informed the National Inventory of Generic Construction Materials Database. For materials that we did not commission research for, we have drawn on the ICE Database – a respected and credible source for generic carbon data of materials based on EPDs and hosted by the University of Bath.
Generic data provides an estimate of the average impact of producing a specific product. It can be used at early design stages to model an overall estimate of a building’s impact. As the design evolves and exact specifications are decided, generic data can be replaced with more specific data from EPDs to give a more accurate picture of the environmental impact of the building.