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Bathroom Fan Ratings

    Scope
    Scope Images
    Image
    Intermittent supply and exhaust fans rated at ≤ 3 sones by manufacturer, unless rated flow ≥ 400 CFM
    Scope

    ENERGY STAR Single-Family New Homes, Version 3/3.1 (Rev. 11) requires that bathroom exhaust fans used as part of a whole-house mechanical ventilation system be ENERGY STAR qualified products.

    • ENERGY STAR exempts fans that have a rated flow of ≥ 500 CFM.

    See the Compliance Tab for related codes and standards requirements, and criteria to meet national programs such as DOE’s Zero Energy Ready Home program, ENERGY STAR Single-Family New Homes, and Indoor airPLUS.

    Description
    Description

    To meet ASHRAE 62.2 ventilation requirements, the HVAC designer may specify that an exhaust fan should be set for continuous or intermittent, timed operation. In homes where the bathroom exhaust fan is used as part of a whole-house mechanical ventilation system, the bathroom fan to be installed should be a model that is ENERGY STAR qualified.

    ENERGY STAR qualified ventilation fans must meet specifications ensuring higher energy efficiency with less noise. These models feature high-performance motors and improved blade design, providing better performance and longer life.

    Fans exempted from this requirement include fans with a rated flow rate equal to or greater than 500 CFM, HVAC air handlers, and remote-mounted fans. To be considered for this exemption, a remote-mounted fan must be mounted outside the habitable spaces and bathrooms and hallways and there must be at least 4 feet of ductwork between the fan and intake grille.

    For more on continuously operating exhaust fans and ASHRAE 62.2 requirements, see Intermittent Supply/Exhaust Fan Ratings and Continuous Supply/Exhaust Fan Ratings.

    How to Select ENERGY STAR-Qualified Bathroom Fans

    1. When specifying and purchasing bathroom fans that will be part of the home’s whole house mechanical ventilation strategy, select fans that are ENERGY STAR qualifying.
    2. To identify ENERGY STAR qualifying exhaust fans:
    The ENERGY STAR logo on the manufacturer’s label indicates this is an ENERGY STAR qualifying exhaust fan.
    Figure 1. The manufacturer’s label found on the inside of this exhaust fan housing includes an ENERGY STAR label at the lower right, indicating that this fan is an ENERGY STAR qualifying model (Source: Courtesy of PNNL). 

     

    Success
    Ensuring Success

    In homes where the bathroom exhaust fan is used as part of a whole-house mechanical ventilation system, the HERS rater should inspect to ensure that the fan is ENERGY STAR qualified.

    To meet the requirements of the DOE Zero Energy Ready Home program, all bathroom exhaust fans installed in the home must be ENERGY STAR qualified.

    Climate
    Climate

    No climate specific information applies.

    Training
    Right and Wrong Images
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    Sone rating is greater than 3.0
    Sone rating is greater than 3.0
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    Wrong - Bathroom fan should have enough suction to hold a tissue.
    Wrong - Bathroom fan should have enough suction to hold a tissue.
    Compliance

    Compliance

    The Compliance tab contains both program and code information. Code language is excerpted and summarized below. For exact code language, refer to the applicable code, which may require purchase from the publisher. While we continually update our database, links may have changed since posting. Please contact our webmaster if you find broken links.

     

    ENERGY STAR Single-Family New Homes, Version 3/3.1 (Rev. 11)

    National Rater Field Checklist

    HVAC System.
    7. Dwelling Unit Mechanical Ventilation Systems (“Vent System”) 45 & Inlets In Return Duct 46
    7.6 Bathroom fans are ENERGY STAR certified if used as part of the Vent System. 53

    Footnote 45) As defined by ANSI / RESNET / ICC Std. 301-2019, a Dwelling Unit Mechanical Ventilation System is a ventilation system consisting of powered ventilation equipment such as motor-driven fans and blowers and related mechanical components such as ducts, inlets, dampers, filters and associated control devices that provides dwelling-unit ventilation at a known or measured airflow rate.

    Footnote 46) Item 7.3 applies to any outdoor air inlet connected to a ducted return of the dwelling unit HVAC system, regardless of its intended purpose (e.g., for ventilation air, make-up air, combustion air). This Item does not apply to HVAC systems without a ducted return.

    Footnote 53) Bathroom fans with a rated flow rate ≥ 500 CFM are exempted from the requirement to be ENERGY STAR certified.

    Please see the ENERGY STAR Single-Family New Homes Implementation Timeline for the program version and revision currently applicable in your state.

     

    DOE Zero Energy Ready Home (Revision 07)

    Exhibit 1 Mandatory Requirements.
    Exhibit 1, Item 1) Certified under the ENERGY STAR Qualified Homes Program or the ENERGY STAR Multifamily New Construction Program.
    Exhibit 1, Item 5) All installed bathroom ventilation and ceiling fans are ENERGY STAR qualified.
    Exhibit 1, Item 6) Certified under EPA Indoor airPLUS.

     

    American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE) 62.2-2010, ASHRAE 62.2-2013, and ASHRAE 62.2-2016

    Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings. The standard applies to spaces intended for human occupancy in single-family homes and multifamily homes that are three stories or less, including manufactured and modular homes. The standard provides minimum acceptable requirements for mechanical and natural ventilation in these spaces.

    More

    More Info.

    Access to some references may require purchase from the publisher. While we continually update our database, links may have changed since posting. Please contact our webmaster if you find broken links.

    References and Resources*
    Author(s)
    U.S. Department of Energy,
    U.S. Environmental Protection Agency
    Organization(s)
    DOE,
    EPA
    Publication Date
    Description
    Information sheet about the benefits of purchasing and installing ENERGY STAR rated fans and ventilation products.
    *For non-dated media, such as websites, the date listed is the date accessed.
    Contributors to this Guide

    The following authors and organizations contributed to the content in this Guide.

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