Technical Booklet G Resistance to the Passage of Sound·Page 30·2.24
Corridor walls and doors - general approach
Separating walls between corridors and flats should control flanking transmission and provide required sound insulation, though doors may reduce the separating wall's sound insulation performance.
The separating walls described in this section should be used between corridors and flats and maisonettes, in order to control flanking transmission and to provide the required sound insulation. However, it is likely that the sound insulation of the separating wall will be reduced by the presence of a door.
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