Controlling sound to make buildings more functional, productive and comfortable Acoustical Assemblies

Acoustical design can be one of the most complex facets of architecture and construction. Depending on the purpose of a building or room, primary acoustical requirements could include sound control between spaces, sound control within a space, or listening efficiency in meeting rooms and auditoriums. Just as technical challenges can vary widely from space to space, so, too, do the choices of materials and design details that can meet them. Thoroughly exploring these options requires time and effort. However, this investment can yield important benefits – happier tenants, higher property values,...

3 USG Acoustical Assemblies User’s Guide This brochure provides: — Comprehensive information about strategies for enhancing acoustics and sound control — Guidelines for selecting USG products and systems to meet acoustical needs in a range of applications — Technical information and test data for featured products and systems Pages Introduction 4 Overview Definitions Components Systems Overview 11 Performance Testing Systems Design 14 Performance Selector Design Details Flanking Path Details Good Design Practices For More Information Technical Service 800 USG.4YOU Web Site www.usg.com

4 USG Acoustical Assemblies Overview Acoustics affect critical aspects of a building’s function, from productivity in office settings and performance quality in theaters and auditoriums, to the price an apartment, condominium or single-family house can command. Understanding how to select a combination of building materials, system designs and construction technologies that will provide the most appropriate sound control is key to creating a successful acoustical design. While the science behind sound is well understood, using that science to create the desired acoustical quality within a building...

5 USG Acoustical Assemblies Definitions Like most specialized fields, the science of acoustics has a language all its own. Some of the most important terms and concepts to be familiar with include: Absorption Percentage of sound waves that a material transforms into heat energy and thereby does not reflect back into the space. Articulation index (AI) A measurement of how well speech can be understood in a space. High AI is desirable in spaces such as auditoriums and theaters and can be achieved with a combination of materials and design details that strategically reflect and absorb sound. Reduced...

Pitch The oscillation rate of a sound wave, which travels as a small pressure change alternating above and below the static (at rest) state of the conducting material. Each cycle of compression and re-expansion is a wave. The number of waves occurring per second is the frequency, which is measured as hertz (Hz); one Hz equals one cycle per second. A sound’s pitch rises as its frequency increases. The human ear can discern sounds ranging from approximately 20 Hz to 20,000 Hz. Human speech ranges between 125 Hz and 4,000 Hz. Reflection The bouncing of sound waves off any hard, smooth wall, ceiling...

7 USG Acoustical Assemblies Components Acoustically-rated systems have been comprehensively tested for sound control. Substitution of any components is not recommended or supported by USG. Refer to the material safety data sheet for each product for complete health and safety information. Ceilings USG Acoustical Ceiling Panels – Available with high NRC, CAC, and combination NRC/CAC ratings – Provide stylish and effective sound control in a full range of commercial applications including retail, healthcare, hospitality, educational and office settings – Combine top-rated acoustical performance...

8 USG Acoustical Assemblies Components Walls and Partitions SHEETROCK® Brand Gypsum Panels – Available in thicknesses of 1/4 to 3/4 for assembling interior partitions with one or more layers per side for effective sound control in any application – Steel-framed resilient partition systems with sound attenuation fire blanket (SAFB) in the partition cavity can achieve up to 65 STC with multi-layer designs, up to 63 STC with double-layer designs, and up to 56 STC with single-layer designs –Wood-framed resilient partition systems with SAFB can achieve up to 59 STC with double-layer designs and up...

9 USG Acoustical Assemblies Plaster Systems – Veneer plaster partitions achieve up to 63 STC in steel-framed resilient systems and up to 52 STC in wood-framed resilient systems – Have achieved 1- to 4-hr. fire-resistance ratings for veneer and conventional systems – Can minimize or eliminate irregularities such as ridging, boarding and nail pops associated with standard drywall construction, plus lower lifecycle costs and greater sustainability – Used in theaters and auditoriums to create reflective surfaces near the stage to reinforce sound For more information see the following brochure: Plaster...

Floor/Ceiling Assemblies LEVELROCK® Floor Underlayment – Low-profile leveling gypsum concrete system increases IIC ratings by as much as 13 points when used with LEVELROCK™ SRB™ sound reduction board or SRM-25™ sound reduction mat – Improves sound control in nominal wood-joist, engineered I-joist, open-web truss, and concrete floor systems – Provides 1- and 2-hr. fire-resistance ratings for wood-framed floor/ceiling assemblies, and 4-hr. ratings for precast concrete assemblies – Available in an unmatched range of compressive strengths from 2,500 to 8,000 psi For more information see the following...

11 USG Acoustical Assemblies Performance Testing Testing provides a measurement of maximum performance potential achieved under controlled laboratory conditions. The actual ability of partitions and assemblies to control sound in real-life applications, however, depends on their design and the methods used to install them. Deviations from the detailing shown in this publication, substitution of components, or damage and improper repair or maintenance could severely reduce the acoustical performance of these installations. Testing Methods All USG products and systems undergo exhaustive testing...