Sound-damping roof-gable ventilation grille - comprises steel plate housing with slots connected by labyrinth air passage

摘要

The sound-dampening roof-gable ventilation grille is mounted in the wall of a building and comprises a housing of steel plate, with ventilation slots. The latter are connected to each other by a labyrinth-pattern air passage. The grille can be of the absorption/resonance type, in the form of a Helmholtz resonator. The passage can be shaped to form several resonance chambers, dimensioned partic. so as to damp out low frequencies, which account for the bulk of traffic noise. A sliding shutter with gauze can be included.