A design team pursuing LEED for a new office building project calculated that with the...

According to the LEED AP Building Design + Construction (LEED AP BD+C) V4 resources, the Water Efficiency Prerequisite for Indoor Water Use Reduction requires the project to reduce aggregate water consumption by 20% from the baseline. Therefore, the project can meet this prerequisite with a 24% water reduction. However, to earn points under the Water Efficiency Credit for Indoor Water Use Reduction, the project needs to achieve a higher level of water reduction, ranging from 25% to 50%. The credit awards points based on the percentage of water reduction achieved, as shown in Table 1. Thus, the project may pursue this credit if it can further reduce its water consumption by installing more efficient fixtures and fittings, appliances, equipment and processes.

As per the LEED AP Building Design + Construction (LEED AP BD+C) V4 resources, the Water Efficiency Prerequisite and Credit for Indoor Water Use Reduction are based on an “efficiency first” approach to water conservation. The prerequisite sets a minimum standard of 20% water reduction from the baseline, while the credit rewards higher levels of performance up to 50% water reduction. The baseline water consumption of fixtures and fittings is based on the volumes and flow rates shown in Table 2. The credit also requires that all newly installed toilets, urinals, private lavatory faucets and showerheads that are eligible for labeling must be WaterSense labeled (or a local equivalent for projects outside the U.S.). For more detailed information, you can refer to the web-based reference guide in the credit library at USGBC’s official website.