Life cycle assessmentLCA

An independently verified document that reports the environmental impacts of a product, based on a life cycle assessment carried out to agreed product category rules. For construction products, EPDs are typically produced to EN 15804, giving specifiers comparable data on embodied carbon and other impact categories.

The greenhouse gas emissions associated with producing a material or product, covering raw material extraction, processing, manufacture and transport, and in whole-building assessments also construction, maintenance and end-of-life stages. It is expressed as carbon dioxide equivalent and is commonly reported through environmental product declarations.

A life cycle assessment boundary covering the full life of a product, from raw material extraction through manufacture, distribution and use to final disposal. It contrasts with cradle to gate, which stops at the factory, and with cradle to cradle approaches in which materials are recovered into new products instead of being disposed of.

A measure of how much heat a greenhouse gas traps in the atmosphere over a set time period relative to carbon dioxide, allowing emissions of different gases to be expressed as a single carbon dioxide equivalent figure. GWP is the headline indicator in most environmental product declarations and carbon footprint studies.

The total greenhouse gas emissions caused directly and indirectly by a product, organisation, activity or service, expressed as carbon dioxide equivalent. Product carbon footprints are normally calculated using life cycle assessment methods over a defined system boundary.