Acoustic partitions
A partition that stops at the ceiling grid stops working at the ceiling grid. Acoustic partitions are built to the slab, sealed, and specified to a target.
Also in openings
Most office and hotel complaints trace back to a partition that looks solid and is not. It stops at the suspended ceiling and leaves the void open above it; or services cross it and were never sealed; or sockets sit back to back in the same stud bay. The wall is then only as good as the path around it, which is usually very much worse than the wall itself.
What we detail
- Construction to the slab — carried to the underside of the structure, not to the ceiling.
- Mass and cavity — layers and spacing chosen for the target, with isolated framing where the target is high.
- Cavity absorption — quilt in the void, which does much more than its cost suggests.
- Perimeter sealing — head, base and abutments, sealed both sides.
- Service crossings — sleeved and sealed; sockets offset rather than back to back.
- Junctions — where the partition meets facade, floor and ceiling, which is where flanking begins.
Flanking: the path around the wall
Sound that bypasses a good partition is called flanking, and in finished buildings it accounts for more failures than the partitions themselves. The usual routes are the ceiling void, a raised floor, a continuous facade mullion, shared ductwork, and structural junctions. We survey for these before specifying, because a heavier wall does nothing about any of them.
| Ceiling void | Partition carried to the slab, or a void barrier installed above the line of the wall. |
|---|---|
| Raised floor | Blocked beneath the partition line. |
| Facade junction | Sealed at the mullion; spandrel void closed. |
| Shared services | Crosstalk attenuators in ducts serving both rooms. |
| Back-to-back outlets | Offset by at least one stud bay and sealed. |
| Structural junction | Detailed so the partition is not a rigid bridge between two structures. |
Setting the target
The number comes from what happens on each side. A meeting room beside an open office is a different problem from a bedroom beside a corridor, and a consulting room where confidentiality is a legal requirement is different again. We survey, agree the figure, build to it, and measure the finished partition — which is the only way anyone finds out whether the detailing survived the site.
Specify performance, not products. A clause naming a quantity and a target can be verified; one naming a brand cannot.
What we need to quote
- Plan and section, with the ceiling and floor build-ups.
- What is on each side, and the separation required.
- Services crossing the line of the partition.
- Fire rating and any structural constraint on fixing.
- Whether adjacent spaces stay in use during the work.
Tell us the room
Send dimensions and intended use. You get back an indicative acoustic treatment, a systems outline and a budget range.