Learn how to accurately determine water use reduction for LEED projects by comparing baseline conditions to the calculated installed case. Boost your LEED exam prep!
Table of Contents
Question
The water use reduction for a project is determined by finding the difference between the baseline conditions and the
A. local water usage rate
B. project occupancy type
C. calculated installed case
D. permitted maximum water usage
Answer
C. calculated installed case
Explanation
The water use reduction for a project is determined by finding the difference between the baseline conditions and the calculated installed case. The baseline conditions are the water use of the project if it were designed to meet the minimum requirements of the Energy Policy Act of 1992 or a local equivalent, whichever is more stringent.
The calculated installed case is the water use of the project based on the actual fixtures and fittings installed or specified. The water use reduction is calculated as a percentage of savings from the baseline conditions.
The LEED Green Associate Candidate Handbook states that one of the strategies for achieving water efficiency is to “calculate water use reduction by comparing a building project’s water use with the water use baseline calculated for the building after meeting the Energy Policy Act of 1992 fixture performance requirements”.
In LEED projects, water use reduction is determined by comparing the baseline water usage to the calculated water usage of the installed fixtures and fittings, known as the “installed case”. The baseline represents the water consumption of a standard building with typical fixtures, while the installed case reflects the expected water usage of the project’s actual low-flow or water-efficient fixtures.
To calculate the water use reduction percentage, follow these steps:
- Determine the baseline water consumption using standard flow rates and flush volumes for each fixture type.
- Calculate the installed case water consumption based on the flow rates and flush volumes of the project’s specified water-efficient fixtures.
- Find the difference between the baseline and installed case water usage.
- Divide the difference by the baseline water usage and multiply by 100 to express the reduction as a percentage.
The other options are incorrect because:
A. Local water usage rates are not used in determining water use reduction for LEED.
B. Project occupancy type is accounted for in both the baseline and installed case calculations but is not the primary factor in determining water use reduction.
D. Permitted maximum water usage is not considered in LEED water use reduction calculations, which focus on comparing baseline and installed case usage.
USGBC LEED Green Associate certification exam practice question and answer (Q&A) dump with detail explanation and reference available free, helpful to pass the USGBC LEED Green Associate exam and earn USGBC LEED Green Associate certification.