Healthcare-v4 EQc9: Acoustic Performance

  • Provide an acoustically superior environment for occupants

    This credit encourages quality acoustical design, which provides many benefits to occupants including increased comfort and productivity. 

    However, the credit requirements can be difficult and expensive to achieve, and can require careful balancing against other project concerns, such as materials selection or open floor planning. Consider enlisting the expertise of an acoustical consultant to ensure your project meets the applicable requirements for all occupied spacesEnclosed space intended for human activities, excluding those spaces that are intended primarily for other purposes, such as storage rooms and equipment rooms, and that are only occupied occasionally and for short periods of time. Occupied spaces are further classified as regularly occupied or nonregularly occupied spaces based on the duration of the occupancy, individual or multioccupant based on the quantity of occupants, and densely or nondensely occupied spaces based on the concentration of occupants in the space.

    For non-U.S. projects, this credit does allow for an alternative compliance path based on local standards. Project teams will have to show that the local standard is equivalent to the ANSI S12.60–2002 standard.

    What’s New in LEED v4

    This is a new credit for New Construction, Data Centers, Warehouses and Distribution Centers, and Hospitality.

    For Schools:

    • USGBC reduced the noise-level limit from 40 to 35 dBAA decibel (dBA) is a sound pressure level measured with a conventional frequency weighting that roughly approximates how the human ear hears different frequency components of sounds at typical listening levels for speech. (ANSI S12.60–2002).
    • The referenced ANSI S12.60 standard was updated from the 2002 to the 2010 version.
    • The background noise AHRI Standard 885–2008 was added as a referenced standard.
    • The credit requires that all equivalent local codes are used in place of national codes.

    For Healthcare:

    • The Acoustic Environment credit name is changed.

    FAQs

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

    Yes, it’s possible. Your project would be required to clearly identify which components of the credit will be implemented as part of the developer’s scope of work, and which portions will be part of the tenant’s scope of work and enforced through binding tenant lease or sales agreements. Both the developer and the tenant must sign a legally binding document that includes the technical credit requirements. The document must explicitly state performance requirements for the tenant work. 

    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 credit asks for a Composite STC rating. This essentially means the transmission loss of the wall in addition to the transmission loss of the door, averaged based on their respective areas. So you won't need an STC 50 rated door assembly, but it may still be hard to achieve an STC 50 composite rating unless you have a large wall area with a high STC rating and a small, standard STC 35-40, door.

    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?

    All occupied spaces listed in Table 1 should be addressed. If the adjacency combination present in the project is not included in the table, select the most appropriate combination or propose an alternative composite STC rating for that combination.

  • EQ Credit 9: Acoustic Performance

    Intent

    To provide workspaces and classrooms that promote occupants’ well-being, productivity, and communications through effective acoustic design.

    Requirements

    Design the facility to meet or exceed the sound and vibration criteria outlined below, which are adapted from the 2010 FGI Guidelines for Design and Construction of Health Care Facilities (“2010 FGI Guidelines”) and the reference document on which it is based, Sound and Vibration Design Guidelines for Health Care Facilities (“2010 SV Guidelines”).

    Option 1. Speech Privacy, Sound Isolation, and Background Noise (1 point)
    Speech Privacy and Sound Isolation

    Design sound isolation to achieve speech privacy, acoustical comfort, and minimal annoyance from noise-producing sources. Consider sound levels at both source and receiver locations, the background sound at receiver locations, and the occupants’ acoustical privacy and acoustical comfort needs. Speech privacy is defined as “techniques … to render speech unintelligible to casual listeners” (ANSI T1.523-2001, Telecom Glossary 2007).

    Design the facility to meet the criteria outlined in the sections of Table 1.2-3, Design Criteria for Minimum Sound Isolation Performance between Enclosed Rooms, and Table 1.2-4 Speech Privacy for Enclosed Room and Open-Plan Spaces (in the 2010 FGI Guidelines and 2010 SV Guidelines).

    Calculate or measure sound isolation and speech privacy descriptors achieved for representative adjacencies as necessary to confirm compliance with the criteria in the 2010 FGI Guidelines, Sections1.2-6.1.5 and 1.2-6.1.6, and the 2010 SV Guidelines (including the appendix).

    Background Noise

    Consider background noise levels generated by all building mechanical-electrical-plumbing systems, air distribution systems and other facility noise sources under the purview of the project building design-construction team.

    Design the facility to meet the 2010 FGI Guidelines, Table 1.2-2 Minimum-Maximum Design Criteria for Noise in representative interior rooms and spaces.

    Calculate or measure sound levels in representative rooms and spaces of each type to confirm compliance with criteria in the above-referenced table using a sound level meter that conforms to ANSI S1.4 for type 1 (precision) or type 2 (general purpose) sound measurement instrumentation. For spaces not listed in Table 1.2-2, refer to ASHRAE 2011 Handbook, Chapter 48, Sound and Vibration Control, Table 1.

    Option 2. Acoustical Finishes and Site Exterior Noise (1 point)

    Meet the requirements for acoustical finishes and site exterior noise.

    Acoustical Finishes

    Specify materials, products systems installation details, and other design features to meet the 2010 FGI Guidelines, Table 1.2-1, Design Room Sound Absorption Coefficients (including associated sections of the appendix) and the 2010 SV Guidelines.

    Calculate or measure the average sound absorption coefficients for representative unoccupied rooms of each type in the building to confirm conformance with the requirements.

    Site Exterior Noise

    Minimize the effect on building occupants of site exterior noise produced by road traffic, aircraft flyovers, railroads, on-site heliports, emergency power generators during maintenance testing, outdoor facility MEP and building services equipment, etc. Also minimize effects on the surrounding community from all facility MEP equipment and activities as required to meet (1) local applicable codes or (2) Table 1.2-1 of the 2010 FGI Guidelines, Table 1.2-1, and the 2010 SV Guidelines, Table 1.3-1, whichever is more stringent.

    Comply with the 2010 FGI Guidelines for the following noise sources:

    • heliports, A1.3-3.6.2.2;
    • generators, 2.1-8.3.3.1;
    • mechanical equipment, 2.1-8.2.1.1;
    • building services, A2.2-5.3

    Measure and analyze data to determine the exterior noise classification (A, B, C, or D) of the facility site. See the 2010 FGI Guidelines, Categorization of Health Care Facility Sites by Exterior Ambient Sound, Table A1.2a, and the 2010 SV Guidelines, Table 1.3-1.

    Design the building envelope composite STCSound transmission class (STC) is a single-number rating for the acoustic attenuation of airborne sound passing through a partition or other building element, such as a wall, roof, or door, as measured in an acoustical testing laboratory according to accepted industry practice. A higher STC rating provides more sound attenuation through a partition. (ANSI S12.60–2002) rating based on the 2010 FGI Guidelines, Categorization of Health Care Facility Sites by Exterior Ambient Sound, and show conformance with requirements.

    For exterior site exposure categories B, C, or D, calculate or measure the sound isolation performance of representative elements of the exterior building envelope to determine the composite sound transmission class (STCc) rating for representative façade sections. Measurements should generally conform to ASTMVoluntary standards development organization which creates source technical standards for materials, products, systems, and services E966, Standard Guide for Field Measurements of Airborne Sound Insulation of Building Façades and Façade Elements, current edition.

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Mar 29 2017
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