What This Template Is
The acoustic design brief template is a structured document that captures all acoustic requirements for a building project at the start of design. It translates client aspirations ("the conference rooms need to be quiet and clear for video calls") into quantified performance targets that the design team can model, specify, and verify.
The template covers eight sections: project overview, building use and programme, room schedule with acoustic classifications, noise environment, regulatory requirements, performance targets, budget and construction constraints, and measurement and verification plan. It is designed to be completed jointly by the acoustic consultant and the client at the initial briefing meeting, then issued to the full design team as a reference document for the duration of the project.
The completed brief feeds directly into AcousPlan's room calculator, where you can model individual rooms against the RT60 and STI targets you have specified.
Why a Formal Brief Matters
Most acoustic design failures can be traced to one of three root causes: wrong performance targets, targets defined too late, or targets that were never communicated to the people making the relevant design decisions.
A project where the acoustic brief is produced at RIBA Stage 1 has its acoustic targets baked into the concept design. Room volumes are sized to achieve target RT60. Noisy plant rooms are located away from quiet offices. The structural engineer knows that party walls need to achieve STC 52 and designs the build-up accordingly. The M&E engineer knows that HVAC noise must meet NC-35 in meeting rooms and selects ductwork and terminal units from the outset.
Contrast this with a project where the acoustic brief arrives at Stage 3: the floor plate is already fixed, the plant room is above the boardroom, and the architect is now being asked to add mass to a wall that has already been detailed in lightweight blockwork. The cost premium for late acoustic engagement is typically 3–5 times higher than equivalent acoustic performance achieved through early design.
Section 1 — Project Overview
The brief opens with a single-page project summary:
- Project name and reference number
- Site address and orientation (relevant for external noise sources)
- Building use (office, residential, school, healthcare, mixed-use)
- Gross internal area (m²) and number of storeys
- Acoustic consultant and contact
- Lead designer (architect / project manager)
- Client representative (the person who confirms acoustic targets)
- RIBA stage at which brief is issued
- Issue date and version number
Section 2 — Building Use and Programme
Describe the building's primary use and the key acoustic challenges it presents. This section is written in plain language for the benefit of team members who are not acoustic specialists.
Example for a mixed-use development:
The building comprises ground-floor retail (3 units), floors 1–4 offices (open plan with meeting rooms), and floors 5–8 residential (24 apartments). The principal acoustic challenge is the separation of the retail and office uses from residential use above, combined with external noise from the adjacent A-road and railway. Internal noise from the building's own plant (ground-floor AHU, roof-mounted cooling towers) must be controlled to avoid impacting residential amenity.
This description sets the context for every subsequent section. It tells the structural engineer that party floors between office and residential are load-bearing acoustic performance elements, not just structural elements.
Section 3 — Room Schedule and Acoustic Classification
The room schedule is the technical core of the brief. Every room or space in the building is listed with its acoustic classification and the standard under which it will be assessed.
| Room Ref | Room Name | Floor Area (m²) | Volume (m³) | Acoustic Class | Standard | Notes |
|---|---|---|---|---|---|---|
| OF-01 | Open Plan Office | 450 | 1,350 | DIN 18041 A4 / BS 8233 | BB100 + client requirement | 40–60 workstations |
| OF-02 | Meeting Room | 25 | 75 | DIN 18041 A3 | Client requirement | Video conferencing equipped |
| OF-03 | Board Room | 60 | 180 | DIN 18041 A3 | Client requirement | Formal presentations |
| OF-04 | Phone Booths (×6) | 4 each | 12 each | DIN 18041 B1 | Client requirement | Enclosed, single occupant |
| RS-01 | Restaurant | 180 | 540 | Client requirement | Target RT60 0.6–0.8 s | Evening use, background music |
| AP-01 | Apartment Living Room | 30 | 75 | BS 8233 / ADE | Building Regulations | Ground-floor residential |
| AP-02 | Apartment Bedroom | 15 | 37 | BS 8233 / ADE | Building Regulations | Requires 35 dB(A) night limit |
For each row, the acoustic class drives the RT60 target. The standard column identifies whether the target is mandatory (Building Regulations, school building codes) or performance-based (WELL v2 Feature 74, BREEAM HEA 05) or client-driven.
Section 4 — Noise Environment
Document all significant noise sources that will affect the building. Divide into external sources and internal sources.
External noise sources:
| Source | Location | Measured Level | Assessment Basis |
|---|---|---|---|
| Road traffic | North boundary | LA10,18h = 68 dB(A) | BS 8233:2014 (BS EN ISO 1996-2) |
| Railway (freight) | East boundary, 120 m | LAmax = 82 dB(A) | BS 8233 / PPG24 |
| Neighbouring factory | South boundary | LA90 = 48 dB(A) | BS 4142:2014 |
Internal noise sources:
| Source | Location | Type | Design Constraint |
|---|---|---|---|
| Air handling unit | Basement plant room | Continuous broadband | Maximum NR-35 at nearest office |
| Cooling towers | Roof | Tonal + broadband | Maximum NR-35 at residential above |
| Goods lift | Core B | Intermittent impact | Maximum LAmax = 45 dB(A) in adjacent apartments |
| Retail music (estimated) | Ground floor | Continuous | Maximum LA90 = 35 dB(A) in offices above |
The noise environment section drives the sound insulation requirements in Section 5. If external road traffic is at LA10 = 68 dB(A) and the target for bedrooms is LA90 = 30 dB(A) (BS 8233 good practice), the façade requires approximately 45 dB(A) of weighted sound reduction — which demands triple glazing, heavyweight masonry, and sealed interfaces.
Section 5 — Regulatory Requirements
List every acoustic regulation, standard, or certification that the project must comply with. Distinguish between legal requirements (Building Regulations, planning conditions) and voluntary commitments (BREEAM, WELL).
Statutory requirements:
- Building Regulations Approved Document E (England & Wales) — sound insulation between dwellings
- Noise impact assessment required under planning condition (reference: PA/2025/00123)
- DIN 4109:2018 — sound insulation requirements for German-specification projects
- WELL v2 Feature 74 (Sound) — prerequisite compliance required for WELL Gold target
- BREEAM New Construction 2018, HEA 05 (Acoustic Performance) — 3 credits targeted
- Maximum background noise NC-35 in all meeting rooms
- STI ≥ 0.70 in boardroom and main presentation space
- RT60 ≤ 0.6 s in all meeting rooms with volume ≤ 100 m³
Section 6 — Performance Targets
This is the quantified specification that the acoustic design must achieve. Every target should reference the room schedule from Section 3.
Reverberation time targets:
| Room Type | RT60 Target | Standard | Frequency |
|---|---|---|---|
| Open plan office | 0.5–0.8 s | DIN 18041 A4 | 500–1,000 Hz |
| Meeting room (< 100 m³) | 0.3–0.6 s | DIN 18041 A3 | 500–1,000 Hz |
| Boardroom (100–200 m³) | 0.4–0.7 s | DIN 18041 A3 | 500–1,000 Hz |
| Restaurant | 0.6–0.8 s | Client requirement | 500–1,000 Hz |
| Apartment living room | 0.4–0.6 s | BS 8233 | 500–2,000 Hz |
Speech intelligibility targets:
| Room Type | STI Target | Standard |
|---|---|---|
| Meeting rooms | ≥ 0.70 | IEC 60268-16 / DIN 18041 A3 |
| Boardroom | ≥ 0.70 | IEC 60268-16 / DIN 18041 A3 |
| Open plan (at workstation) | ≥ 0.50 | ISO 3382-3 |
Background noise level targets:
| Room Type | Background Noise Limit | Measurement Standard |
|---|---|---|
| Open plan office | ≤ NC-40 | ANSI S12.2 |
| Meeting rooms | ≤ NC-35 | ANSI S12.2 |
| Boardroom | ≤ NC-30 | ANSI S12.2 |
| Residential bedroom (night) | ≤ 30 dB(A) LA90 | BS 8233:2014 |
| Residential living room (day) | ≤ 35 dB(A) LA90 | BS 8233:2014 |
Sound insulation targets:
| Partition | Required STC/Rw | Standard |
|---|---|---|
| Meeting room to meeting room | STC 45 minimum | ASTM E90 / WELL F74 |
| Office to office (cellular) | STC 42 minimum | Building Regulations |
| Apartment to apartment (airborne) | DnT,w + Ctr ≥ 45 dB | Approved Document E |
| Apartment to apartment (impact) | L'nT,w ≤ 62 dB | Approved Document E |
Section 7 — Budget and Construction Constraints
Acoustic treatment budget: Document the approximate budget available for dedicated acoustic materials (ceiling tiles, wall panels, raised floors, floating floors). This constrains the design options available to the consultant.
Construction constraints: List any constraints that limit acoustic performance:
- Lightweight steel frame (limits partition mass available for STC performance)
- Floor-to-floor height of 3.5 m (limits ceiling plenum depth for ductwork silencers)
- Listed building status (limits the ability to add mass to existing walls)
- Pre-installed HVAC system (consultant must accept existing ductwork noise levels)
- Partition specifications required by [date] for contractor pricing
- Post-construction measurement before practical completion
Section 8 — Measurement and Verification Plan
Specify how acoustic compliance will be verified after construction:
| Parameter | Rooms | Test Standard | Acceptance Criteria | Test Party |
|---|---|---|---|---|
| RT60 | All meeting rooms, boardroom | ISO 3382-2:2008 | Per targets in Section 6 | Independent acoustic consultant |
| STI | Boardroom, main presentation room | IEC 60268-16:2020 | ≥ 0.70 | Independent acoustic consultant |
| Airborne sound insulation | Selected party walls/floors | ISO 16283-1:2014 | Per Section 6 | UKAS-accredited testing lab |
| Impact sound insulation | Selected party floors | ISO 16283-2:2015 | Per Section 6 | UKAS-accredited testing lab |
| Background noise | All meeting rooms, open plan | ANSI S12.2 | Per Section 6 | Acoustic consultant |
Issue the verification plan to the contractor at start of construction. Pre-practical-completion testing requires the contractor to agree to testing access and to remedy any failures before handover.
How to Use This Template With AcousPlan
Once your room schedule is complete and RT60 targets are set, use AcousPlan's room calculator to model each room and check whether the proposed finishes will achieve the brief targets:
- Enter room dimensions from your room schedule
- Select surface materials from the materials database (acoustic ceilings, carpet, plasterboard)
- AcousPlan calculates predicted RT60 across all octave bands
- Compare predicted RT60 against your brief targets
- The tool shows the absorption deficit or surplus and suggests additional treatment where needed
Related Resources
- Acoustic Design Process: 8 Steps — how the brief fits into the wider design workflow
- Acoustic Contractor Specification Guide — translating the brief into a contractor-ready specification
- Room Acoustic Calculator — model your rooms against brief targets before specifying materials
Template structure references RIBA Plan of Work 2020 stage definitions, BS 8233:2014 Table 4, DIN 18041:2016 §4, IEC 60268-16:2020, ANSI S12.2:2019, and ISO 3382-2:2008. AcousPlan calculations are advisory and should be verified by a qualified acoustic consultant.