The complaint is always the bass
Neighbour complaints about a music venue are remarkably consistent: a thumping pulse that is clearly rhythmic but carries no tune. That is the subwoofer and the kick drum, roughly 40 to 80 Hz, the range that passes through construction most easily under the mass law — and a range STC does not even describe, because the measurement starts at 125 Hz.
The path out of a venue is rarely the wall that looks thinnest. In practice it is the entrance door opening and closing all evening, the kitchen extract and make-up air openings, a ceiling void running continuously over the demising wall into the next tenancy, service penetrations, and a subwoofer standing directly on the slab and feeding the structure. That last one cannot be fixed by adding mass to a wall at all.
Which grade, and why
A public assembly space carries a fire requirement, and concealed materials inside walls and ceilings are the first thing asked about at inspection. BB830FR is the grade for that work, and it is the one product in the range whose fire performance does not rest on manufacturer data. It was tested by an independent third party: AS/NZS 1530.3:1999, SGS report AJFTS26000525R01_EN dated 3 February 2026, indices of 0/0/0/7 for ignitability, spread of flame, heat evolved and smoke developed, with none of the six specimens igniting.
Where the wall is shared with a residential neighbour and the complaint is bass, BB830LF is formulated for low-frequency work. The standard BB830 grade — nominally 5 kg/m² at about 3 mm, STC 32 as a material, according to the manufacturer’s datasheet, reference BB830/20/v2 — remains the sensible choice for back-of-house areas with no particular constraint.
| Grade | Where it goes | What the evidence is | Price |
|---|---|---|---|
| BB830FR | Walls and ceilings in the public areas, where a fire requirement applies | Independent third-party test: SGS to AS/NZS 1530.3:1999, indices 0/0/0/7 | 1,288 /m² (1,204) |
| BB830LF | The demising wall to a residential neighbour, where bass is the complaint | Formulated for low frequency; manufacturer data | 1,761 /m² (1,646) |
| BB830 | Back of house, stores, plant rooms | Nominally 5 kg/m² at about 3 mm, STC 32, laboratory value, manufacturer data | 1,122 /m² (1,049) |
| BA890 sealant | Every perimeter, joint and penetration | Non-flammable, manufacturer data | 321 /cartridge (300) |
| BA650 putty pad | Backing socket and switch boxes in the demising wall | Fire tested to ASTM E814, manufacturer data | 385 /pad (360) |
The sequence that works in a venue
- Decouple the subwoofer from the slab before spending anything on walls. A cabinet standing on structure feeds the building directly.
- Close the ceiling void at the demising line and seal it. If the void runs on, most of the wall work below it is wasted.
- Make the entrance a lobby, so there is no moment when the room is open straight to the street.
- Line the demising wall with BB830FR or BB830LF, bonded with BA990, sheets overlapped at the joints.
- Seal every perimeter with BA890 and back every socket and switch box with BA650.
- Overboard with 12 mm plasterboard and seal the board perimeter again before finishing.
What a lining will not fix
- Patrons outside — the smoking area, the pavement, closing time. That is management, not material, and it is what most complaints are actually about.
- Structure-borne bass from a subwoofer on the slab. Treat the mounting and the level, not the wall.
- Kitchen extract and make-up air. These need attenuators that pass air; a barrier sheet over a duct opening is not an option.
- Reverberation inside the room, which is why guests have to shout. That is absorption, a different material and a different problem.
- A heavy concrete demising wall already carrying several hundred kg/m². Adding about 5 kg/m² changes nothing audible.
- Club-level bass held to a strict limit. Mass alone will not do it; that needs a double-leaf construction with a real cavity and mineral wool, plus level control in the room.
Two Bangkok venues the material was supplied for
IAC Acoustics (Thailand) supplied BlastBlock material for both of the projects below. Neither was installed by IAC; both were installed by others. On an outdoor screen the seal at the base and the returns at the ends decide the result far more than the sheet does. The figures are quoted according to the project documentation held by BlastBlock, and IAC has not verified them independently.
A rooftop bar in Sukhumvit had music and crowd noise carrying to the residential towers around it. A barrier was built into the terrace edge and the pergola soffit and then concealed behind the planting, so the open-air character of the room was kept. According to the project documentation the barrier reduced noise by up to 20 dB, and the before and after noise mapping shows the high-level contour over the building pulled back inside the site boundary.
A hotel courtyard restaurant in Bangkok had an open dining terrace exposed to a noise source immediately outside the boundary. A barrier panel was erected between that source and the seating, leaving the restaurant’s existing planted screen untouched. According to the project documentation the level at the terrace fell from 85 dB(A) to 66 dB(A), a reduction of 19 dB(A).