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Making Walls Quiet for Less White Paper ® 09 29 00/NGC Gold Bond brand SoundBreak ®XP ® Gypsum Board Market Trends Driving The Need For Higher Rated STC Wall Partitions Increasing land costs have resulted in larger amounts of high density multi-family housing in a growing number of United States housing markets. The result of high density housing is individual living units positioned closer together than traditional single-family housing. Home theatre systems are becoming more prevalent in use and sophis- tication, resulting in the potential for more noise being transmitted between wall partitions. Commercial buildings such as schools, hospitals, hotels and government/military facilities also have an increasing need to control sound between areas of a building. All of these changing market dynamics have resulted in an increased need for higher rated Sound Transmission Class (STC) wall partitions, which reduce the transmission of airborne sound between living spaces within buildings. Gold Bond® brand SoundBreak® XP® Gypsum Board Gold Bond® brand SoundBreak XP Gypsum Board is an acoustically enhanced gypsum board used in the construction of high STC wall assemblies. This innovative gypsum board allows for construction of high STC wall assemblies that are thinner, cost effective and more reliable than traditional methods for constructing these types of assemblies. SoundBreak XP Gypsum Board allows for construction of higher STC area separation walls. 2 Key Acoustical Terms and Concepts Airborne Sound Decibel Airborne sound consists of energy The level of airborne sound is Decibels (dB) are used in acoustics most human’s ears, while a change generated by a source, transmitted determined by the intensity of the to provide relative measurement of of 5 dB would generally be notice- through a medium, and detected vibration. Frequencies between sound level. Higher dB levels relate able to most people. An increase by a receiver. All three of these 20 Hz and 20,000 Hz are detectible to loud sounds while lower dB levels of 10 dB would sound twice as conditions must be in place or by children. Most humans are relate to quiet sounds. A change of loud and a decrease of 10 dB airborne sound cannot exist. The sensitive to the range of 100 Hz 3 dB would be barely noticeable to would sound half as loud. following chart describes what to 5000 Hz. Speech and other happens when a drumstick strikes traditional sounds within a building RATING ACTIVITY SOUND LEVEL (dB) a drumhead. range from 125 Hz – 4,000 Hz, Painful Jet Engine . .120+ which is the frequency range Very Loud Industrial Machinery . .100 considered when calculating STC. Loud Stock Trader Floor . .80 Moderate Normal Speech . .65 SOUND TRANSMISSION Quiet Suburban Home . .45 Energy Generated Transmitted Detected by by a Source Through a Medium a Receiver Very Quiet Barely Audible . .25 Drumstick strikes Vibrating air Ear receives and drumhead, transmits the hears waves of HUMAN SENSITIVITY TO CHANGES IN SOUND INTENSITY LEVELS vibrating air sound in waves of pressure changes pressure changes as sound 1 dB Generally not perceptible 3 dB Just perceptible 5 dB Clearly noticeable Sound Transmission Class 10 dB Twice or half as loud 20 dB Four times as loud or 1/4 as loud The Sound Transmission Class Method for Laboratory Measurement (STC) is a single number rating of of Airborne Sound Transmission the effectiveness of a material or Loss of Building Partitions. The test construction assembly to retard the data collected would be analyzed transmission of airborne sound. using ASTM E 413 Classification for Design Considerations STC provides an indication of how Rating Sound Insulation and result in Acoustical Wall Partitions loud transmitted sound is perceived in a single-number acoustical rating. by the listener. Higher STC values The rating assesses the airborne The goal of a high rated STC Damping are more effective for reducing sound transmission performance at wall partition is to decrease the Introduction of damping will sound transmission. a range of frequencies from 125 Hz amount of sound transmission increase the amount of sound through the partition. The following transmission loss. In particular, STC values are derived by conducting to 4000 Hz, which is consistent with the frequency range of speech. five variables can have an impact constrained layer damping can a test according to a procedure on the ability of the partition to be effective for structure type outlined in ASTM E 90 Standard provide this loss. applications. Mass Cavity Depth What is an Acceptable STC Rating Increasing the mass of a wall Increasing the depth of the cavity for a Wall Partition? partition increases the amount of of the partition can increase the National Research Council of Canada Survey sound transmission loss. Increasing amount of sound transmission mass in a cost and space effective loss, especially when the cavity is m 600 multi-family residences (300 party walls between them) way can be a challenge. filled with acoustical insulation. m Residents with lower STC rated walls are more likely to: Stiffness Cavity Absorption – Want to move Increasing the stiffness of a wall Adding sound-absorbing material – Be awakened by noises partition will decrease the amount such as fiberglass or mineral – Have trouble falling asleep due to noises of sound transmission loss. For fiber insulation to the cavity of a – Think neighbors are less considerate that reason metal studs outperform partition will increase the amount General survey conclusions wood studs, and 24" o.c. framing of sound transmission loss. The m STC ≥55 A realistic goal for acceptable sound insulation spacing outperforms 16" o.c. sound-absorbing material should framing spacing. completely fill the cavity but not m STC ≥60 More ideal, would practically eliminate negative effects be compacted or compressed of noises from neighbors in any way. m Music related sounds may require the highest rated walls J. S. Bradley, Deriving Acceptable Values for Party Wall Sound Insulation survey results 3 Heavy Abrasion ® Mold and Moisture Resistant Gold Bond brand Face Paper ® ® Viscoelastic SoundBreak XP Polymer Gypsum Board Heavy Abrasion Enhanced Mold and High Density Moisture Resistant Mold Resistant Core Back Paper Description Features/Benefits m 5/8" SoundBreak XP features a m SoundBreak XP Gypsum Board ® ® ® fire resistant Type X core and is must be kept dry to minimize Gold Bond brand SoundBreak XP m Resists the growth of mold UL Classified and approved for the potential for mold growth. Gypsum Board has an acoustically per ASTM G 21 with a score inclusion in specific UL fire-rated Adequate care should be enhanced, high density gypsum core of 0, the best possible score. designs. taken while transporting, stor- encased in a heavy, abrasion and m Resists the growth of mold m SoundBreak XP Gypsum Board ing, applying and maintaining mold/mildew/ moisture resistant, per ASTM D 3273 with a score SoundBreak XP Gypsum Board. 100% recycled, purple paper on is GREENGUARD Children & of 10, the best possible score. SchoolsSM Certified for indoor For additional information, refer both sides. Used in the construction to the Gypsum Association of high rated STC wall assemblies, m Use of SoundBreak XP Gypsum air quality. Board results in wall partitions publication, “Guidelines for the SoundBreak XP consists of a layer m Approved for use on walls and Prevention of Mold Growth on of viscoelastic damping polymer with high rated STC values that ceilings. are thinner than traditionally Gypsum Board”(GA-238-03), sandwiched between two pieces which is available at gypsum org. of high density mold resistant built high rated STC wall Limitations partitions providing increased under the “Download Free gypsum board, providing constrained m usable floor space. Exposure to excessive or con- Gypsum Association Publications” layer damping. tinuous moisture and extreme section. m Superior sound damping, temperatures should be avoided. Basic Uses cost-efficient material that is SoundBreak XP Gypsum Board Accessories easily finished and decorated in For use as single-layer application is not recommended where it (See Installation the same manner as standard or as a component of multi-layered will be exposed to temperatures Recommendations) wall assemblies where sound gypsum board. exceeding 125°F (52°C) for m Fasteners: Drywall Screws transmission between rooms or m All SoundBreak XP Gypsum extended periods of time. dwelling units is a concern. or Nails Board designs were tested by an m Installing SoundBreak XP Gypsum independent third-party acoustical Board panels over an insulating m Joint Tape How SoundBreak XP laboratory using the full-scale blanket, installed continuously m Joint Compound ASTM E90 test procedure. Gypsum Board across the face of the framing m Cornerbead Works m SoundBreak XP Gypsum Board is members, is not recommended. m installed like traditional gypsum Blankets should be recessed Trims board, offering a more reliable and flanges attached to the m Casing Beads sides of the studs. High density core and less complicated solution m Acoustical Sealant provides than alternative methods m SoundBreak XP Gypsum Board m Acoustical Putty Pads increased mass requiring clips and/or channels. must be stored off the ground m SoundBreak XP Gypsum Board and under cover. Sufficient Installation Viscoelastic can be cut by scoring deeply risers must be used to ensure Applicable Standards and polymer provides from both sides of the board support for the entire length of constrained layer References damping before snapping, or with the the gypsum board to prevent use of a hand or power saw. sagging. ASTM C 840 m Heavy abrasion resistant paper Gypsum Association GA-216 and denser core provide greater Gypsum Association GA-214 resistance to surface abuse and indentation when tested in National Gypsum accordance with ASTM C 1629. Gypsum Construction Guide Recommendations m Features a smooth, heavy face paper that is highly resistant to Installation of SoundBreak XP scuffing and provides a superior Gypsum Board should be consis- surface for decoration.
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