The Teen Room That Stopped Echoing: Acoustic Baffles at the Westwood Public Library

The teen room at the Westwood Public Library in Westwood, Massachusetts is one of the building's best spaces, a tall, open room of about 34 by 30 feet under a soaring wood roof-deck ceiling, with a dramatic wall of glass. It is also exactly the kind of room that fights you acoustically. DDS Acoustical Specialties treated it with suspended acoustic baffles and brought its reverberation time down from 2.24 seconds to a calculated 0.90 second, a 60% reduction, then carried the work into three small rooms, the library's podcast room and private study rooms, with twelve fabric-wrapped wall panels.

It is a clear example of what good acoustic design does for libraries: it keeps the architecture that makes a space special while making it comfortable to actually use.

The teen room's best features were also its acoustic problem. A wood roof-deck ceiling, a wall of glass, and gypsum walls over thin carpet are all hard, reflective surfaces with very little ability to absorb sound. With almost nothing to soak it up, sound energy bounced from surface to surface instead of fading.

A site assessment measured the room's reverberation time at 2.24 seconds. At that level, every word overlaps the echo of the word before it. A handful of teenagers can fill the entire room with sound, conversation gets louder to compete with itself, and the space becomes tiring rather than welcoming. For a room meant to support reading, studying, and hanging out, the acoustics were working against everyone in it.

Reverberation time, or RT60, is how long it takes sound to fade by 60 decibels after the source stops. Lower numbers mean speech is clearer and a room feels calmer. A library is comfortable in the range of roughly 0.6 to 1.0 second. At 2.24 seconds, this room was more than twice as live as it should be. If you want the full explainer, see our guide to reverberation time in room acoustics.

The fix is not to deaden a room until it feels dead. It is to add the right amount of absorption in the right places so that speech stays clear and the space stays comfortable. That starts with measurement, which is why every project begins with an acoustic assessment.

Because the teen room is tall and open, the most effective place to add absorption was overhead. DDS Acoustical Specialties suspended 55 acoustic baffles below the wood-slat ceiling, hung vertically so each one absorbs sound from both faces. Suspended acoustic baffles pull mid and high frequency energy out of a room without any wall work, and they go in quickly. Finished in teal, they read as a deliberate design feature against the warm wood rather than equipment added after the fact.

The work did not stop at the teen room. DDS Acoustical Specialties also added twelve fabric-wrapped acoustic wall panels, four in each of three small rooms, including the library's podcast room and private study rooms, finished in colors keyed to each space. Treating the overhead plane in the big room and the walls in the small rooms is what brings a building like this under control, because each space gets absorption aimed at the reflections that actually matter there. This kind of targeted, multi-space approach is the heart of echo and reverberation reduction.

The teen room was treated with semi-rigid fiberglass acoustic baffles, each a semi-rigid fiberglass core finished in a durable facing and hung from the ceiling on grommets. They are an economical, high-performing way to quiet a tall, open room.

• Acoustics: NRC up to 1.15
• Fire rating: Class A, tested per ASTM E-84
• Sizes: built to order, up to 4 feet by 10 feet
• Thickness: 1 inch, 1.5 inch, or 2 inch core
• Finishes: PVC, fabric, or sailcloth
• Mounting: grommet suspension on wire or cable

The teen room used 55 baffles at 2 feet by 4 feet, in a teal facing. The result is broadband absorption spread evenly across the ceiling, where it does the most good in a room this tall.

Learn more about Semi-Rigid Baffles

p>The baffles were fabricated to size, delivered to the site, and installed by the DDS Acoustical Specialties team, including the suspension hardware. Because baffles hang from the existing structure and need no wall work, the teen room install was clean and quick, with minimal disruption to a working library. The twelve wall panels across the three small rooms went in the same way, mounted directly to the walls.

The treatment brought the teen room's reverberation time down to a calculated 0.90 second, a 60% reduction from the original 2.24 seconds and a level well suited to a library. Overall sound energy drops by about 4 decibels, a difference the ear hears clearly.

The room feels different the moment you walk in. Voices stay where they belong, a group of teens no longer fills the whole floor, and the space invites you to read or talk without raising your voice. The wood ceiling and the wall of glass are still the stars of the room. They just no longer make it ring.

Every room has an answer, and it starts with understanding the space you have. Try our room analysis calculator to estimate your own room, browse more finished work in our project gallery, or see a similar school project in our case study on gym baffles and wall panels at Las Americas ASPIRA Academy. When you are ready, we will measure the problem, model the fix, and handle the install.