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Acoustic Design in Education: Creating the Perfect Learning Environment

Quiet please! A recent study has reported that many students have difficulty understanding nearly 30 percent of classroom speech due to excessive noise and sound reverberation. Proper acoustic design in education spaces is vital for successful learning environments for teachers and students alike.

So, how do you create the best learning environment?

In classrooms around the world, innovations in technology and access to learning resources are changing the way we’re educating students and have driven changes in classroom design. Space configuration, lighting, and building structure all play a role in shaping the learning experience.

Proper sound management in the classroom is a vital ingredient in the success of teachers and students alike, and classroom acoustic issues cannot be resolved without concentrated efforts on the parts of the architects and designers involved in casting the vision for these important education spaces.

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Teachers and students suffer from poor classroom acoustics

According to the American Speech-Language-Hearing Association (ASHA), classrooms with poor acoustics interfere directly with teaching and learning. Students with hearing loss or  learning disabilities have the greatest difficulties.

Even teachers are adversely affected and are 32 times more likely to suffer from voice problems, just because of poor acoustics in the classroom.

To encourage beneficial acoustic design, let’s take a look at some of the ways schools and organizations are improving learning and teaching environments when it comes to sound quality.

Better Acoustic Design in Education Spaces Starts with Better Standards

The American National Standards Institute (ANSI), along with the U.S. Access Board and Acoustical Society of America, created the Acoustical Performance Criteria, Design Requirements and Guidelines for Schools standard (or the ANSI S12.60-2002).

The standard developed by ANSI addresses the issues of both reverberation time and background noise in classrooms, and their effect on speech intelligibility. We’ll break down some of the numbers for you:

Maximum reverberation time:

  • in an unoccupied classroom with a volume under 10,000 cubic feet is 0.6 seconds
  • 0.7 seconds for a classroom between 10,000 and 20,000 cubic feet

Maximum level of background noise:

  • 35 decibels (dBA)

These requirements apply to the design of brand new classrooms or learning spaces of small-to-moderate size, and to renovated spaces.

When we look at the numbers, though, you’ll see that most classrooms have noise levels that more than exceed the recommended maximum level. Average noise levels in most classrooms can range between 66 decibels (dB) and 94dB, and one 2001 study found that average classroom noise levels were 72dB — similar to standing next to a busy intersection. (Source)

The ANSI standard is voluntary, unless otherwise specified by a school system or other regulations. Several schools across the US now voluntarily comply with the ANSI standards for noise in classroom settings.  Connecticut and Minnesota, as well as New York City public schools have adopted the ANSI standards across the board. Additionally, the New Hampshire Department of Education, the Ohio School Facility Commission, and the New Jersey School Construction Board have accepted the ANSI rule as their standard for acoustic design in classrooms.

Many school districts, including those in New York, Los Angeles, and Washington D.C. have developed their own directives for acoustic design standards.

Although these standards are currently voluntary, if you’re in the process of developing a design for educational spaces, we recommend you consider these as the minimum standard. How your project performs once it’s inhabited by students is just as important as the end visual result.

Architects and Acoustics: Improving Classrooms at the Design Phase

The State of Texas is pushing to improve acoustics in classrooms, starting at the architectural design phase.

In Texas, 64 architects focused on school design participated in a research study via the ASHA to explore how architects employ acoustic design in schools. The goal of the study was to find a way to include acoustic performance criteria for classrooms, which is omitted from the Architectural Barriers Act and is currently voluntary. From the survey of these architects, several key elements of design were highlighted to help create the perfect learning environment, including:

  • knowledge of acoustical performance criteria for learning environments
  • practices they, as architects, employed to address acoustics in their design
  • attitudes around the earlier published version of the ANSI standard

The survey found, however, that only one-third of the architects were actually aware of the American National Standards Institute (ANSI) standard for hearing, despite the negative effects they perceived in learning environments where acoustics didn’t meet standards.

By educating architects and designers about these acoustic design standards, any architect would be better prepared to design a better, more acoustically sound learning environment.

Green Street Academy: Sustainably Built and Acoustically Sound

Architects looking for ways to improve acoustic design might also look to Baltimore, Maryland for an excellent case study of creating proper acoustic design in a historical building .

The Green Street Academy (GSA) is public charter school in Baltimore, Maryland providing an education for middle and high school students. The GSA has been certified as a LEED BD+C school since 2009, achieving LEED Platinum status in 2016. This is the highest possible ranking under the LEED stature, and the school has plenty to show for it.

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In addition to being highly efficient with water, energy, and green materials, the school features acoustical performance in all classrooms and learning areas. To create an acoustic design, the renovation of the nearly 100-year-old building reused sustainable and recycled materials for the walls and flooring.

The Future of Education and Better Learning Environments

With schools like Green Street Academy setting the bar higher and continued advancements in acoustic materials and design, architects and building owners have the resources they need and standards to guide them towards better acoustic design.

By educating themselves about the standards established, architects are better prepared to design a better, more acoustically sound learning environment, to improve learning experiences for students and teachers alike.

 

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A Learning Curve: Fixing Classroom Acoustics

If you can’t hear what the teacher is saying, it can be difficult to learn. Classrooms and lecture halls are often plagued by poor sound quality, as these vital rooms aren’t always a top design concern for the typical interior designer or architect. But they should be — especially the classroom acoustics, since good sound quality can be the difference between good or bad learning outcomes for students.  

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Luckily acoustic issues can be remedied, often with simple and subtle design changes that enhance the learning environment for students (without blowing the budget).

A few straightforward acoustic concepts can change the way you look at a space:

Reverberation

The main acoustic measurement that impacts classrooms is reverberation time, or how long it takes for sound to reach a destination from its source and other reflected paths.

The  real-life way to think about this is shouting into a canyon – the time it takes for your shouted “ECHO” to come back, is reverberation time. In smaller enclosed spaces this echo time can be difficult to discern, but it’s there and if there’s too much due to hard surfaces or large room volumes, getting it wrong can make or break a space.

EP-Panel-151-ceiling-installation-school-Intrinsic-4A listener has a hard time when multiple echos of the speakers’ voice reach their ear at varying times.  A better room has short reverberation time, so sounds reach the listener all at once and are therefore clearer.

If a lecture or lesson is being given in a space with poor acoustics, the sound of the lecturer’s voice can echoing around the room before reaching the listeners and the result is low speech intelligibility. (Think Charlie Brown’s teachers).

With long reverberation times, clarity and understanding can be diminished and learning impacted.

Speech Intelligibility

Although an invisible design issue in learning environments, many schools in the United States have classrooms with less than 75 percent speech intelligibility.

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Design & Photo: Urbanikz i.d.s.

This means that, at best, only 75 percent of what is being said is actually being heard, creating an issue for the average student and an even bigger disadvantage for students already coping with a learning disability.

Speech intelligibility is measured by the Speech Transmission Index in noisy or reverberating locations. Various software is used to determine these calculations, as the method relies on a lot of different factors including speech level, background noise level, reverberation time, and echos.

Background Noise

Noise from nearby classrooms, students in the halls, or adjacent outside areas can introduce significant distraction as well. When unnecessary sound creeps into the classroom, students lose the ability to concentrate, which can affect their academic performance overall, and even in younger children, can affect their behavior in the classroom.

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Design: Studio DW Fabricator: Greater Texas Construction Services Photos: Gail McCleese + De Toledo

For this reason it is essential to soundproof classrooms from outside sound, to help students maintain focus. This is done by selecting the correct materials for walls, floors and ceilings and properly sealing windows and doors.

Solving The Noise Problem

It’s also crucial to realize that, because of the unique materials, products, and uses of various rooms in schools, there is no single correct answer to fix the acoustic issues.

There is no simple formula that reads “Seven acoustic baffles + three acoustic hanging screens + an acoustic panel = problem solved” — we wish that was the case, but it just is not true, which is why dealing with a professional right off the bat is your best bet.

Especially in the education world where resources are typically limited, there is a fear that designing a space with good acoustics is going to cost a lot of money — something that schools typically don’t have a constant abundance of.

classroom-2093745_1920However, taking acoustics into consideration before the physical building is standing or remodeled and students are running through the halls can be significantly less expensive than fixing a building after it exists.

If you have a preexisting structure to work with, there are many budget-conscious additions you can use in your space.

ACT ceilings or black fiberglass soundboard can be used. Acoustical deck is also a smart decision.

Placement of sound absorbent material should also be considered. Since sound echo, it would be best to install the sound absorbing material on the wall opposite of where a teacher or professor might typically stand in a room, and a wall adjacent to that “back” wall.

It’s important to also install the material between 3-7 feet above the finished floor, since that’s the typical range where sound is reflected.

Ask The Expert

Consult an acoustician (not as expensive as it sounds!) to get some perspective into what the acoustic issues will be in a space.

classroom-2093744_1920The consultants can help determine how you can fix classroom acoustics before anything is built, which will not only help schools keep costs down later on, but will also grant deserving students the ability to clearly hear and comprehend their lessons.

Need some more information about acoustics? Download our “Understanding Acoustic Design” PDF to learn valuable information from a professional acoustic consultant.