The LEED for Homes Rating System (v4) addresses acoustic comfort in the Indoor Environmental Quality (EQ) Credit: Enhanced Ventilation, which includes requirements for bathroom exhaust fans to ensure they are quiet to encourage use and maintain indoor air quality.

According to the LEED Reference Guide for Homes Design and Construction (v4):

EQ Credit: Enhanced Ventilation (1--3 points)

For bathroom exhaust fans, select equipment with a maximum noise level of 1.0 sone to support acoustic comfort and encourage regular use. Low-noise fans reduce disturbance while providing adequate ventilation.

Source: LEED Reference Guide for Homes Design and Construction, v4, Indoor Environmental Quality Credit: Enhanced Ventilation, p. 146.

The LEED v4.1 Residential BD+C rating system confirms:

EQ Credit: Enhanced Ventilation

Bathroom exhaust fans must not exceed 1.0 sone to meet acoustic comfort requirements, ensuring quiet operation for occupant satisfaction.

Source: LEED v4.1 Residential BD+C, Credit Library, accessed via USGBC LEED Online.

The maximum sone level for bathroom exhaust fans is 1.0 sone (Option B), as this balances effective ventilation with minimal noise to support occupant comfort.

Why not the other options?

A . 0.5: This is more stringent than required and may limit fan options, as 1.0 sone is the standard for acoustic comfort in LEED.

C . 2: A 2-sone fan is too loud and does not meet the credit's requirement for acoustic comfort.

D . 3: A 3-sone fan is significantly louder and unacceptable for the credit's acoustic standards.

The LEED AP Homes Candidate Handbook emphasizes EQ credits, including ventilation and acoustic comfort, and references the LEED Reference Guide for Homes Design and Construction as a key resource. The exam is based on LEED v4, ensuring the relevance of the 1.0 sone limit.

References:

LEED Reference Guide for Homes Design and Construction, v4, USGBC, Indoor Environmental Quality Credit: Enhanced Ventilation, p. 146.

LEED v4.1 Residential BD+C, USGBC LEED Credit Library, accessed via LEED Online (https://www.usgbc.org/credits).

LEED AP Homes Candidate Handbook, GBCI, October 2024, p. 12 (references study resources and exam scope based on LEED v4).

USGBC LEED for Homes Rating System (v4), available via USGBC website (https://www.usgbc.org/resources/leed-homes-design-and-construction-v4).

LEED v4.1 for Homes, USGBC, accessed via LEED Online, confirming sone level requirements.