Make a keel on the wall, fill the gap of the keel with sound-absorbing cotton, and then cover it with perforated plate.

Sound insulation of doors

At the same time, the sound insulation of the door should be done well. It is best to use soundproof doors. If it is simple, solid wood doors or steel doors can be used, but the door cover cannot be empty and must be filled.

Window sound insulation

Sound insulation of windows is very important. The window area of the classroom is very large, so it should be made of double glass or laminated glass, and the surrounding area should be filled with cement. It is best to use plastic-steel casement windows, which have poor sound insulation effect. The aluminum-plastic window hardware is useless and the sound insulation is poor. The sealing strip of the window should be used better, and there is no sound insulation effect after aging.