Acoustics

Back to PRO FAQ's

Are there different types of sound ratings?
Yes. The three types of acoustical performance ratings include Noise Reduction Coefficient (NRC), Ceiling Attenuation Class (CAC), and Articulation Class (AC).

What is NRC?
NRC measures the sound absorption characteristics of a ceiling panel. It is calculated by averaging sound absorption coefficients at 250, 500, 1000 and 2000 Hz. The higher the range, the better the sound control in a space.

What minimum NRC values can be used in open plan offices?
Open plan offices should use ceiling panels with a minimum NRC range of .65-.75. For most other spaces, panels with a minimum NRC of .45-.55 are generally recommended for effective noise reduction, regardless of application.

What CGC ceiling panels have the highest NRC values?
CGC offers two ceiling panels: Mars™ ClimaPlus™ High NRC, with values ranging from .80 to .95, based on product thickness and Premier Nubby™ ClimaPlus™ with NRC of .80 to .95 based on thickness. Both products are made of a fiberglass basemat laminated with a scrim.

What is CAC?
CAC, or Ceiling Attenuation Class, is a measure of the sound transmission loss as noise travels between rooms. Essentially, it is the ability of a ceiling panel to block sound between rooms.

What spaces require CAC values?
CAC values are essential in interior spaces that require physical separation from other areas such as conference and board rooms, private offices, bathrooms, and corridors.

Is CAC important in open plan offices?
Actually, CAC is important to assure privacy for areas outside or adjoining an open plan such as private offices or conference rooms.

What CGC ceiling panels have the best CAC values?
SHEETROCK® Brand Lay-In Ceiling Tile, ClimaPlus™ has the highest CAC value of 45-49. Numerous other CGC ceiling panels offer a high CAC value of 40-44.

What is AC?
AC, or Articulation Class, is a measurement of ceiling sound attenuation (in dB) which represents the ability to hear or understand transmitted or processed speech within a space.

Where is AC important?
AC is important in open office space, where conventional noises, including speech, are less likely to be blocked due to the absence of full-height partitions. The acceptable AC range for open office spaces is 170-210.

What CGC ceiling panels have the best AC ratings?
Mars™ ClimaPlus™ High NRC panels with AC 180 to 190 (based on product thickness) provide the best USG ceiling-panel AC range.

What is the significance of the UL Mark?
The presence of the Underwriters Laboratories, Inc. (UL) Mark provides assurance that a product has been rigorously tested and that its production is monitored for compliance with designated safety and performance standards. UL classifies acoustical materials (including ceiling panels) for CAC, NRC, and AC. Acoustical performance is determined by laboratory measurements in accordance to the most current published editions of the applicable ASTM standards.

What CGC products are UL certified?
All CGC Ceilings™* are classified by UL for acoustical performance and carry the UL Mark. Our ceilings meet or exceed published performance values for NRC, CAC, and AC. UL's classification assures you that USG adheres to recognized ASTM standard test methods.*Excluding SHEETROCK® Brand Lay-In Ceiling Tile, ClimaPlus™

 

Back to PRO FAQ's



More SEARCH 
Dust Control Drywall Compound East