855773520-LEED-v5-ID-C-Reference-Guide-Launch-Edition-1 - Page 085

Extracted Content

REQUIREMENTS EXPLAINED

This prerequisite identifies minimum water efficiency requirements for fixtures, fittings, appliances, and process water. Two compliance options exist for fixture and fitting efficiency.

Minimum Fixture and Fitting Efficiency

Reducing potable water use for fixtures and fittings begins with conservation efforts. Selecting high-efficiency fixtures reduces water consumption and demand. The selection of high efficiency fixtures can lead to savings from reductions in pump energy and water heating requirements. For example, selecting these fixtures for lavatories, faucets, and showerheads reduces the electrical load required for water heating.

Choose either a prescriptive or performance pathway to demonstrate compliance for fixture and fitting efficiencies.

OPTION 1. PRESCRIPTIVE PATH — MAXIMUM FLUSH AND FLOW RATES

The prescriptive path offers a streamlined approach for the prerequisite. Table 1 outlines the maximum allowable flush or flow rate for fixtures and fittings within the project boundary. All fixtures and fittings installed must not exceed these maximum values.

For projects that install dual-flush toilets, the volume of the full flush must be used when calculating flush rate. The full-flush rate must not exceed 1.28 gallons per flush (gpf) (4.8 liters per flush (lpf)). Projects cannot use a fixture with a weighted average flow of 1.28 gpf (4.8 lpf).

Teams conducting projects in the U.S. and Canada are encouraged to use WaterSense-labeled toilets (water closets), urinals, private lavatory faucets, and showerheads. WaterSense-labeled products require testing and verification for efficiency by third-party vendors. These products comply with U.S. Environmental Protection Agency (U.S. EPA) specifications.

OPTION 2. PERFORMANCE PATH — CALCULATED REDUCTION

Using the performance-based approach, teams can maximize water conservation across all applicable fixtures and fittings within the project boundary. Teams pursuing points under WEc2: Enhanced Water Efficiency should consider Option 2. Performance Path — Calculated Reduction to show prerequisite compliance. Compliance with WEp1: Minimum Water Efficiency, Option 2. Performance Path — Calculated Reduction and WEc2: Enhanced Water Efficiency, Option 2. Fixture and Fittings — Calculated Reduction requires documented compliance through the USGBC-approved calculator.

U.S. Green Building Council LEED v5 Reference Guide for Interior Design and Construction, April 2025 Launch Edition 74