Technical Booklet G Resistance to the Passage of Sound·Page 30·2.25
Door performance in separating walls
Doors in separating walls must have good perimeter sealing and either minimum mass of 25 kg/m² or a sound reduction index of 29 dB Rw.
Ensure that any door in a separating wall has good perimeter sealing (including the threshold where practical) and a minimum mass per unit area of 25 kg/m2 or a minimum sound reduction index of 29 dB Rw (measured according to BS EN ISO 140-3 and rated according to BS EN ISO 717-1).
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