Controlling Noise In Classrooms

Acoustical performance is vital ceiling selection criteria for classrooms. The reason: students must be able to hear and understand their teacher if they are to learn.

In the past, acoustical ceilings offered either good sound absorption to decrease unwanted sound levels in a classroom, or good ceiling attenuation to block unwanted sound intrusion from adjacent classrooms or corridors, but not both absorption and blocking in the same ceiling.

Now, the science behind the ceiling is able to offer a new generation of acoustical ceiling panels that provide an ideal combination of sound absorption as denoted by their Noise Reduction Coefficient (NRC) and sound blocking as denoted by their Ceiling Attenuation Class (CAC) in the same panel.

The NRC indicates the ability of a ceiling to absorb sound. It is expressed as a number between 0.00 and 1.00, and indicates the percentage of sound it absorbs. An NRC of 0.60 means a ceiling absorbs 60 percent of the sound that strikes it. A ceiling with an NRC less than 0.60 is considered low-performance, one with an NRC of 0.70 or greater, high-performance.

The CAC indicates the ability of a ceiling to block sound in one space from passing up into the plenum and transmitting back down into an adjacent space that shares the same plenum. The higher the number, the better the ceiling acts as a sound barrier.

A ceiling with a CAC less than 25 is considered low-performance, one with a CAC of 35 or greater, high-performance.

Regardless of whether it’s new construction or renovation, the best solution for both reducing the level of sound in a classroom and limiting sound intrusion into it is an acoustical ceiling panel that combines an NRC of 0.70 or greater and a CAC of 35 or greater.

This article originally appeared in the issue of .

About the Author

Sean Browne is principal scientist - Global Acoustics for Armstrong Ceilings.

Featured

  • University of Pennsylvania Releases Design of Future Physical Sciences Building

    The University of Pennsylvania (Penn) in Philadelphia, Penn., recently released renderings of an upcoming 350,000-square-foot Physical Sciences Building, according to news release. The facility was designed by CO Architects and will unite the university’s departments of Physics and Astronomy, Mathematics, and Earth and Environmental Science.

  • Back-to-School Playground Safety: 7 Common Hazards to Look for After Summer Break

    As summer break comes to an end, school administrators have plenty to prepare before students return. While classrooms, hallways and common areas often receive attention during all the back-to-school preparations, the playground should not be overlooked. Months of weather exposure, storms, and regular wear can leave behind hazards that may not be immediately noticeable.

  • Nashville Elementary School Receives LEED Gold Certification

    Goodlettsville Elementary School, part of Metro Nashville Public Schools in Nashville, Tenn., recently achieved LEED Gold Certification from the U.S. Green Building Council (USGBC), according to a news release. The 81,750-square-foot school opened in 2023 and was designed by Goodwyn Mills Cawood (GMC).

  • University of Mary Washington Selects Builder for New Theater, Dance Facility

    The University of Mary Washington in Fredericksburg, Va., recently announced that it has selected construction and development firm Skanska to lead a series of renovations and upgrades to fine arts facilities, according to a news release.