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LEED v4
Data Centers – NC
Indoor Environmental Quality
Acoustic performance

LEED CREDIT

Data-Centers-NC-v4 EQc9: Acoustic performance 1 point

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View the LEED v4.1 version of this credit »

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LEED AP BD+C

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Credit language

USGBC logo

© Copyright U.S. Green Building Council, Inc. All rights reserved.

Requirements

For all occupied spaces, meet the following requirements, as applicable, for HVAC background noise, sound isolation, reverberation time, and sound reinforcement and masking.

HVAC Background Noise
Achieve maximum background noise levels from heating, ventilating, and air conditioning (HVAC) systems per 2011 ASHRAE Handbook, HVAC Applications, Chapter 48, Table 1; AHRI Standard 885-2008, Table 15; or a local equivalent. Calculate or measure sound levels. For measurements, use a sound level meter that conforms to ANSI S1.4 for type 1 (precision) or type 2 (general purpose) sound measurement instrumentation, or a local equivalent. Comply with design criteria for HVAC noise levels resulting from the sound transmission paths listed in ASHRAE 2011 Applications Handbook, Table 6; or a local equivalent.
Sound Isolation
Meet the composite sound transmission class (STCC) ratings listed in Table 1, or local building code, whichever is more stringent.
Table 1. Minimum composite sound transmission class ratings for adjacent spaces

Adjacency combinations

STCC

Residence (within a multifamily residence), hotel or motel room

Residence, hotel or motel room

55

Residence, hotel or motel room

Common hallway, stairway

50

Residence, hotel or motel room

Retail

60

Retail

Retail

50

Standard office

Standard office

45

Executive office

Executive office

50

Conference room

Conference room

50

Office, conference room

Hallway, stairway

50

Mechanical equipment room

Occupied area

60

Reverberation Time
Meet the reverberation time requirements in Table 3 (adapted from Table 9.1 in the Performance Measurement Protocols for Commercial Buildings1).
Table 2. Reverberation time requirements

Room type

Application

T60 (sec), at 500 Hz, 1000 Hz, and 2000 Hz

Apartment and condominium

—

Hotel/motel

Individual room or suite

Meeting or banquet room

Office building

Executive or private office

Conference room

Teleconference room

Open-plan office without sound masking

Open-plan office with sound masking

Courtroom

Unamplified speech

Amplified speech

Performing arts space

Drama theaters, concert and recital halls

Varies by application

Laboratories

Testing or research with minimal speech communication

Extensive phone use and speech communication

Church, mosque, synagogue

General assembly with critical music program

Varies by application

Library

 

Indoor stadium, gymnasium

Gymnasium and natatorium

Large-capacity space with speech amplification

Classroom

—

Sound Reinforcement and Masking Systems
Sound Reinforcement For all large conference rooms and auditoriums seating more than 50 persons, evaluate whether sound reinforcement and AV playback capabilities are needed. If needed, the sound reinforcement systems must meet the following criteria:
  • Achieve a speech transmission index (STI) of at least 0.60 or common intelligibility scale (CIS) rating of at least 0.77 at representative points within the area of coverage to provide acceptable intelligibility.
  • Have a minimum sound level of 70 dBA and must
  • Maintain sound-level coverage within +/–3 dB at the 2000 Hz octave band throughout the space.
Masking Systems For projects that use masking systems, the design levels must not exceed 48 dBA. Ensure that loudspeaker coverage provides uniformity of +/–2 dBA and that speech spectra are effectively masked.

1 Adapted from ASHRAE (2007d), ASA (2008), ANSI (2002), and CEN (2007)

 See all forum discussions about this credit »

What does it cost?

Cost estimates for this credit

On each BD+C v4 credit, LEEDuser offers the wisdom of a team of architects, engineers, cost estimators, and LEED experts with hundreds of LEED projects between then. They analyzed the sustainable design strategies associated with each LEED credit, but also to assign actual costs to those strategies.

Our tab contains overall cost guidance, notes on what “soft costs” to expect, and a strategy-by-strategy breakdown of what to consider and what it might cost, in percentage premiums, actual costs, or both.

This information is also available in a full PDF download in The Cost of LEED v4 report.

Learn more about The Cost of LEED v4 »

Frequently asked questions

Is it possible to pursue this as an Innovation credit in a Core & Shell project?

The answer to this question is available to LEEDuser premium members. Start a free trial »

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Our project has small meeting rooms in an open-office plan. This situation appears to require an STC of 50. However, this level seems to be (unrealistically) high, especially considering the doors in the wall partition. STC 50 with a (closed) wall can be achieved, but even high STC doors won't achieve an STC of more than 45. Would this mean that the credit is not achievable?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

Sound transmission requirements for adjacency combinations are listed in Reference Guide Table 1, but not all combinations are included. For example, an STC rating requirement is not provided for conference room and standard/executive office adjacency. Is sound transmission compliance achieved by addressing only project applicable adjacency combinations listed in Table 1?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

Are we required to have an acoustical consultant in order to attempt this credit?

The answer to this question is available to LEEDuser premium members. Start a free trial »

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See all forum discussions about this credit »

Addenda

4/6/2018 – Updated: 11/6/2020
Reference Guide Correction
Description of change:
Add an International Tips section that reads:

"The International Electrotechnical Commission (2013) IEC 61672-1:2013 Electroacoustics – Sound Level Meters – Part 1: Specifications are considered to be an equivalent to ANSI S1.4. Project teams outside the U.S. may use measuring equipment which is in line with IEC 61672-1:2013."
Campus Applicable
No
Internationally Applicable:
Yes
4/6/2018 – Updated: 5/1/2018
Rating System Correction
Description of change:
In Table 2, revise the T60 value for Office Building Open Plan Office with Sound Masking to read as "
Campus Applicable
No
Internationally Applicable:
No
7/11/2017 – Updated: 7/18/2017
Form Update
Description of change:
Updated Sound Transmission (Isolation) tab to allow for "other" space type
Campus Applicable
Yes
Internationally Applicable:
Yes
4/1/2015 – Updated: 4/1/2015
Reference Guide Correction
Description of change:
Replace TABLE 1 header with: TABLE 1. Minimum composite sound transmission class ratings for adjacent spaces
Campus Applicable
No
Internationally Applicable:
No
4/1/2015 – Updated: 4/1/2015
Rating System Correction
Description of change:
Replace TABLE 1 header with: TABLE 1. Minimum composite sound transmission class ratings for adjacent spaces
Campus Applicable
No
Internationally Applicable:
No
10/1/2014 – Updated: 2/14/2015
Form Update
Description of change:
Revised Instructions and Summary tabs to include ID+C rating systems

Campus Applicable
No
Internationally Applicable:
No
10/1/2014 – Updated: 2/14/2015
Reference Guide Correction
Description of change:
Change 'Equation 1' to 'Equation 2' so the first sentence reads "Equation 2 must be calculated separately..."
Renumber Equation 1 to Equation 2.
Renumber Equation 2 to Equation 3.
Renumber Equation 3 to Equation 4.
Campus Applicable
No
Internationally Applicable:
No
See all forum discussions about this credit »

Documentation toolkit

The motherlode of cheat sheets

LEEDuser’s Documentation Toolkit is loaded with calculators to help assess credit compliance, tracking spreadsheets for materials, sample templates to help guide your narratives and LEED Online submissions, and examples of actual submissions from certified LEED projects for you to check your work against. To get your plaque, start with the right toolkit.

LEEDuser expert

headshot

Ken Shook

LEED AP BD+C

Longman Lindsey
Partner

Get the inside scoop

Our editors have written a detailed analysis of nearly every LEED credit, and LEEDuser premium members get full access. We’ll tell you whether the credit is easy to accomplish or better left alone, and we provide insider tips on how to document it successfully.

USGBC logo

© Copyright U.S. Green Building Council, Inc. All rights reserved.

Requirements

For all occupied spaces, meet the following requirements, as applicable, for HVAC background noise, sound isolation, reverberation time, and sound reinforcement and masking.

HVAC Background Noise
Achieve maximum background noise levels from heating, ventilating, and air conditioning (HVAC) systems per 2011 ASHRAE Handbook, HVAC Applications, Chapter 48, Table 1; AHRI Standard 885-2008, Table 15; or a local equivalent. Calculate or measure sound levels. For measurements, use a sound level meter that conforms to ANSI S1.4 for type 1 (precision) or type 2 (general purpose) sound measurement instrumentation, or a local equivalent. Comply with design criteria for HVAC noise levels resulting from the sound transmission paths listed in ASHRAE 2011 Applications Handbook, Table 6; or a local equivalent.
Sound Isolation
Meet the composite sound transmission class (STCC) ratings listed in Table 1, or local building code, whichever is more stringent.
Table 1. Minimum composite sound transmission class ratings for adjacent spaces

Adjacency combinations

STCC

Residence (within a multifamily residence), hotel or motel room

Residence, hotel or motel room

55

Residence, hotel or motel room

Common hallway, stairway

50

Residence, hotel or motel room

Retail

60

Retail

Retail

50

Standard office

Standard office

45

Executive office

Executive office

50

Conference room

Conference room

50

Office, conference room

Hallway, stairway

50

Mechanical equipment room

Occupied area

60

Reverberation Time
Meet the reverberation time requirements in Table 3 (adapted from Table 9.1 in the Performance Measurement Protocols for Commercial Buildings1).
Table 2. Reverberation time requirements

Room type

Application

T60 (sec), at 500 Hz, 1000 Hz, and 2000 Hz

Apartment and condominium

—

Hotel/motel

Individual room or suite

Meeting or banquet room

Office building

Executive or private office

Conference room

Teleconference room

Open-plan office without sound masking

Open-plan office with sound masking

Courtroom

Unamplified speech

Amplified speech

Performing arts space

Drama theaters, concert and recital halls

Varies by application

Laboratories

Testing or research with minimal speech communication

Extensive phone use and speech communication

Church, mosque, synagogue

General assembly with critical music program

Varies by application

Library

 

Indoor stadium, gymnasium

Gymnasium and natatorium

Large-capacity space with speech amplification

Classroom

—

Sound Reinforcement and Masking Systems
Sound Reinforcement For all large conference rooms and auditoriums seating more than 50 persons, evaluate whether sound reinforcement and AV playback capabilities are needed. If needed, the sound reinforcement systems must meet the following criteria:
  • Achieve a speech transmission index (STI) of at least 0.60 or common intelligibility scale (CIS) rating of at least 0.77 at representative points within the area of coverage to provide acceptable intelligibility.
  • Have a minimum sound level of 70 dBA and must
  • Maintain sound-level coverage within +/–3 dB at the 2000 Hz octave band throughout the space.
Masking Systems For projects that use masking systems, the design levels must not exceed 48 dBA. Ensure that loudspeaker coverage provides uniformity of +/–2 dBA and that speech spectra are effectively masked.

1 Adapted from ASHRAE (2007d), ASA (2008), ANSI (2002), and CEN (2007)

Cost estimates for this credit

On each BD+C v4 credit, LEEDuser offers the wisdom of a team of architects, engineers, cost estimators, and LEED experts with hundreds of LEED projects between then. They analyzed the sustainable design strategies associated with each LEED credit, but also to assign actual costs to those strategies.

Our tab contains overall cost guidance, notes on what “soft costs” to expect, and a strategy-by-strategy breakdown of what to consider and what it might cost, in percentage premiums, actual costs, or both.

This information is also available in a full PDF download in The Cost of LEED v4 report.

Learn more about The Cost of LEED v4 »

In the end, LEED is all about documentation. LEEDuser’s Documentation Toolkit, for premium members only, saves you time and helps you avoid mistakes with:

  • Calculators to help assess credit compliance.
  • Tracking spreadsheets for materials purchases.
  • Spreadsheets and forms to give to subs and other team members.
  • Guidance documents on arcane LEED issues.
  • Sample templates to help guide your narratives and LEED Online submissions.
  • Examples of actual submissions from certified LEED projects.

Is it possible to pursue this as an Innovation credit in a Core & Shell project?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

Our project has small meeting rooms in an open-office plan. This situation appears to require an STC of 50. However, this level seems to be (unrealistically) high, especially considering the doors in the wall partition. STC 50 with a (closed) wall can be achieved, but even high STC doors won't achieve an STC of more than 45. Would this mean that the credit is not achievable?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

Sound transmission requirements for adjacency combinations are listed in Reference Guide Table 1, but not all combinations are included. For example, an STC rating requirement is not provided for conference room and standard/executive office adjacency. Is sound transmission compliance achieved by addressing only project applicable adjacency combinations listed in Table 1?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

Are we required to have an acoustical consultant in order to attempt this credit?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)
4/6/2018 – Updated: 11/6/2020
Reference Guide Correction
Description of change:
Add an International Tips section that reads:

"The International Electrotechnical Commission (2013) IEC 61672-1:2013 Electroacoustics – Sound Level Meters – Part 1: Specifications are considered to be an equivalent to ANSI S1.4. Project teams outside the U.S. may use measuring equipment which is in line with IEC 61672-1:2013."
Campus Applicable
No
Internationally Applicable:
Yes
4/6/2018 – Updated: 5/1/2018
Rating System Correction
Description of change:
In Table 2, revise the T60 value for Office Building Open Plan Office with Sound Masking to read as "
Campus Applicable
No
Internationally Applicable:
No
7/11/2017 – Updated: 7/18/2017
Form Update
Description of change:
Updated Sound Transmission (Isolation) tab to allow for "other" space type
Campus Applicable
Yes
Internationally Applicable:
Yes
4/1/2015 – Updated: 4/1/2015
Reference Guide Correction
Description of change:
Replace TABLE 1 header with: TABLE 1. Minimum composite sound transmission class ratings for adjacent spaces
Campus Applicable
No
Internationally Applicable:
No
4/1/2015 – Updated: 4/1/2015
Rating System Correction
Description of change:
Replace TABLE 1 header with: TABLE 1. Minimum composite sound transmission class ratings for adjacent spaces
Campus Applicable
No
Internationally Applicable:
No
10/1/2014 – Updated: 2/14/2015
Form Update
Description of change:
Revised Instructions and Summary tabs to include ID+C rating systems

Campus Applicable
No
Internationally Applicable:
No
10/1/2014 – Updated: 2/14/2015
Reference Guide Correction
Description of change:
Change 'Equation 1' to 'Equation 2' so the first sentence reads "Equation 2 must be calculated separately..."
Renumber Equation 1 to Equation 2.
Renumber Equation 2 to Equation 3.
Renumber Equation 3 to Equation 4.
Campus Applicable
No
Internationally Applicable:
No

LEEDuser expert

headshot

Ken Shook

LEED AP BD+C

Longman Lindsey
Partner

See all LEEDuser forum discussions about this credit » Unsubscribe from discussions about Data-Centers-NC-v4 EQc9 View the LEED v4.1 version of this credit