The London offices of this FTSE 100 financial services group provides a central base for the chairman, CEO and other executives. The board met once a month at this location and during these and other sensitive meetings it became necessary to leave all other rooms empty as speech could be clearly heard. The sound travelled predominantly through the metal perforated ceiling tile and the ceiling plenum, but a full acoustic study was commissioned and identified a number of weaknesses in the partition system and a general lack of absorption.
The 40 plus page report detailed every weakness and made recommendations to solve the speech privacy issue. The solution was three fold:
- A contractor was commissioned to block all the gaps in the partitions using a PU foam.
- The LogiSon® Sound Masking System was installed in the ceiling plenum to raise the background sound.
- A layer of 40mm Rockwool was fitted into every perforated ceiling tile in the offices and meeting rooms.
The solution has proved so effective that the PA to the Chairman can no longer tell if he was in his office and the board now sits every month with all meeting rooms in use.
Sound level tests: cellular office
These example test results measure sound leaking from a closed meeting room into an open plan area.
- For both tests, a person was positioned in the conference room with the door closed.
- Sound pressure measurements were taken in the open plan area.
- For the first half of each test, there was no speech.
- For the second half, the person in the conference room spoke with a ‘presentation’ voice.