What metric is commonly used to calculate water efficiency in LEED projects?

The metric commonly used to calculate water efficiency in LEED projects is indoor water use measured in gallons per capita per day. This measurement provides a standardized way to assess the water usage of the building as it accounts for occupancy levels—allowing for a more accurate representation of the facility's water efficiency. By expressing water consumption in relation to the number of occupants, it enables project teams to set benchmarks for performance improvements and compare different projects effectively.

Recognizing the occupancy factor in indoor water use is crucial for the LEED certification process, as it directly relates to the goal of promoting water conservation practices in the built environment. This benchmarking also allows for easier identification of opportunities for reducing water use through improved fixtures and systems.

Other metrics, such as annual water usage, while informative, do not provide the same context regarding the number of users and their behavior. Percentage reduction from baseline is a useful measure for showing improvements over previous usage levels but does not inherently provide clarity on the per capita aspect. Water quality rating assesses the suitability of water for specific uses but does not directly address water efficiency in terms of consumption metrics like gallons per capita per day does.