Sustainable Building Glossary

Embodied Energy: A Life Cycle Analysis (LCA) shows the embodied energy which is the primary energy¹¹consumed in the manufacture of a material in MJ kg^-1. The embodied energy can consist of renewable energy such as wind power or animal fats or non-renewable energy such as coal or natural gas. A true LCA should properly account for the proportion of non-renewable energy¹² embodied within a material as this has a particularly harmful effect on the environment. The BRE classifies this energy as primary energy consumption.

Equilibrium moisture content (EMC): EMC means the moisture content of a material at a fixed temperature and at a fixed humidity of the ambient air, assuming that the material is given sufficient time to reach a stable state. The hygroscopic mechanism is understood to operate only up to 95 % humidity. At levels of humidity higher than this capillary mechanisms start to operate as water vapour starts to become liquid firstly in the finer pores and then in larger ones.