Walls in classrooms are usually drywall, block or glass, all of which reflect almost all of the sound that reaches them. Educational occupancy: wall and ceiling finishes generally must be Class A, and ANSI/ASA S12.60 sets a 0.6 s limit for core learning spaces under 10,000 ft³.
Treat reflection points first
A reflection point is a spot on a wall where sound from a source bounces to a listener. You can find them with a mirror: sit where people listen, have someone slide a mirror along the wall, and mark each spot where you can see a sound source. Panels there give the biggest improvement per square foot.
Parallel walls and flutter echo
Two bare parallel walls make a fast, buzzing echo when you clap. One panel on each wall, offset from each other, usually stops it. See flutter echo between drywall walls.
Recommended wall products
- Essential: Offices, living rooms, classrooms, from $95
- Capsule: Offices, cafés, children's rooms, from $58
- Grid Tile: Offices, schools, healthcare, from $49
If the wall needs to block sound too
Panels do not add meaningful STC to a wall. If sound coming through the wall is a problem, read soundproofing and STC for classrooms and what STC means.