Unnoticed noise in classrooms disrupts learning. Here’s how to spot it and what to do.
What’s that sound?
Walk into a classroom and you might hear the usual suspects: pencils tapping, whispered questions, a sneeze here or there. But underneath that everyday hum, there’s a whole other layer of noise that often goes unnoticed, and unaddressed. These aren’t just momentary distractions. They’re environmental stressors that impact everything from student literacy rates to teacher retention.
The overlooked sources of classroom noise.
When we talk about classroom noise, people often assume we’re talking about chatter. But research, and field experience, shows that some of the most disruptive sounds come from the building itself.
Common culprits include:
- HVAC systems with rattling ductwork or poorly insulated rooftop units
- Adjacent spaces like gyms, band rooms, or stairwells
- Traffic or train noise in urban environments
- Poor acoustical design, causing sound to bounce and amplify across hard surfaces
- Open-concept classrooms or portable buildings that lack physical barriers
These noises often sit in the low-frequency range, which our brains struggle to filter out, especially for students who are still developing key language and literacy skills.
Problem: Students can’t hear clearly.
Let’s talk about speech intelligibility: the ability to understand spoken words. It’s a concept at the heart of every classroom. After all, if students can’t hear clearly, they can’t learn effectively. For younger students, the stakes are even higher.
Early reading instruction is rooted in phonics—the ability to hear and distinguish between sounds in a word. If a student can’t hear the difference between “cat” and “cap,” their brain doesn’t register those sounds as distinct. That misunderstanding compounds over time, impacting reading fluency and comprehension.
According to the Acoustical Society of America, even moderate background noise can drop speech intelligibility to 75% or lower—meaning 1 in 4 words is lost. That’s not just inconvenient. It’s instructional failure.
Problem: Noise makes it harder to focus.
Noise is cognitively exhausting. Research shows that chronic exposure to noise increases stress hormone levels, reduces working memory, and increases error rates in students.
Even when they’re not consciously reacting, students are spending extra mental energy trying to tune out irrelevant sound so they can tune in to the lesson.
When noise levels spike, classroom management goes out the window:
- Students fidget more
- Transitions take longer
- Teachers raise their voices and repeat themselves
It’s a recipe for reduced engagement and increased frustration for everyone in the room.
Problem: Teachers can’t keep up.
Let’s not forget the other people impacted by poor acoustics: the teachers. In noisy classrooms, teachers report:
- Vocal fatigue from constantly speaking louder
- Difficulty maintaining student attention
- Higher stress and burnout rates
According to the University of Melbourne, teachers in high-noise classrooms are more than twice as likely to report symptoms of burnout compared to peers in quieter schools. When a school loses a teacher due to environmental stress, it’s not just a staffing issue, it’s a student achievement issue.
So, what can be done?
The good news? Classroom noise isn’t inevitable. It’s a solvable design and engineering challenge.
At Ketchum & Walton, we work with school architects, facility managers, and design teams to:
- Isolate mechanical equipment from learning spaces
- Engineer quieter, low-vibration rooftop units
- Integrate acoustical treatments that reduce reverb
- Apply zoning strategies to separate noisy areas (like gyms and music rooms) from classrooms
- Ensure systems support high speech intelligibility across every room
We often talk about equity in education, but it’s hard to level the playing field when some students literally can’t hear the lesson. Noise control might not be the flashiest part of school design, but it’s one of the most impactful. When you improve acoustical performance, you improve reading scores, lower teacher turnover, and give students a better shot at success—one decibel at a time.