Acoustic Partitions

What acoustic partitions are

Acoustic partitions are stud wall assemblies specified to achieve a defined sound reduction index (Rw) between adjacent rooms. They are distinct from standard metal stud partitions because every element of the assembly, stud gauge, board specification and number of layers, mineral wool density and thickness, fixing centres, perimeter detailing and service penetration treatment, must match the manufacturer's tested system document for the target Rw. An acoustic partition that is assembled with the wrong board, the wrong insulation, a compressed mineral wool infill or inadequate perimeter sealing will deliver significantly less acoustic performance than specified, often without visible indication until the occupier complains.

We install acoustic partitions to the confirmed manufacturer system document for every project. Where an acoustic consultant has specified the target Rw and the assembly type, we install verbatim. Where the target is known but the assembly is not yet specified, we recommend and price the tested assembly from the manufacturer's documentation.

Performance levels and applications

Standard meeting room performance (Rw 43 to 45 dB) is the minimum for most commercial meeting room briefs. This level provides adequate speech privacy for standard business conversations and allows the meeting room to function without occupants being overheard in adjacent open-plan space. A 70 mm metal stud with a single layer of 12.5 mm standard board each side and 50 mm mineral wool infill typically achieves around Rw 38 to 42 dB, which is below the meeting room threshold. Achieving Rw 43 to 45 dB requires additional board layers, denser insulation or a wider stud, all of which are specified from the manufacturer's tested assembly.

Confidential meeting rooms and boardrooms (Rw 50 to 55 dB) require assemblies that go beyond additional board layers. Staggered stud construction, where the studs on each face of the partition are in separate tracks and do not share a structural connection, breaks the direct vibration path between the two faces. Resilient bar fixing, where the board is screwed to a resilient metal channel rather than directly to the stud, further reduces direct transmission. Dense mineral wool infill completes the assembly. These assemblies are specified for executive offices, legal and financial meeting rooms, HR consultation rooms, and healthcare consultation suites.

Healthcare consultation rooms under HTM 08-01 typically require at least Rw 45 dB between a consultation room and adjacent clinical or waiting space. GP surgery and dental consultation rooms, hospital outpatient consultation suites, and mental health facility interview rooms all fall within this brief. We are experienced with healthcare acoustic briefs and the additional constraints on perimeter sealing and infection-control compatibility that healthcare partition installations require.

The flanking path problem

Laboratory-tested Rw figures overstate in-situ performance because laboratory tests eliminate flanking transmission. In a real building, sound travels around the partition as well as through it: above the suspended ceiling through the shared void, through the structural slab via the partition head and base, through shared ventilation ductwork and through service penetrations such as electrical boxes and pipework sleeves.

The practical implication is that a partition correctly installed to its tested Rw may deliver 5 to 10 dB less in-situ performance if flanking paths are not controlled. The most common failures are: a partition terminated at the suspended ceiling face rather than run to the structural soffit; an acoustic barrier above the ceiling that is not fully sealed to the structure on both sides; electrical back-boxes installed back to back through the partition; and service penetrations that are sleeved but not acoustically sealed.

We address flanking path control as part of the acoustic partition package, agreeing the strategy with the acoustic consultant at pre-start, extending partitions to structural soffit where required, sealing penetrations to the tested system specification, and coordinating the work above the suspended ceiling with the M&E contractor.

Compliance and standards

Acoustic partition performance in education is typically specified to Building Bulletin 93 (BB93) Rw requirements for classroom boundaries: Rw 45 dB for classroom-to-classroom, Rw 50 dB for music rooms and drama studios adjacent to teaching space. In healthcare, HTM 08-01 provides the acoustic performance targets for each room type. In offices, the acoustic brief typically comes from the architect or acoustic consultant working from the tenant's operational requirements.

We install to the manufacturer's tested system document on every acoustic partition, provide the system reference for inclusion in the building's O&M documentation, and coordinate with the acoustic consultant where one is appointed.

Get in touch

If you are specifying acoustic partitions for a commercial, education or healthcare project, we would be glad to discuss the brief. Send drawings, the acoustic brief or the consultant's Rw targets with the form on this page and we will come back with a clear next step within one working day. For urgent enquiries call 01332 757830 or email enquiries@eastledge.co.uk.