How Are Acoustics Shown on Architectural Drawings?

You cannot draw sound in quite the same way as you draw a wall, window or staircase.

Sound is invisible, changes with frequency and can travel through several parts of a building at once. Its effect also depends on how the space is used, the surrounding noise, the building construction and the people listening.

That does not mean acoustics are absent from architectural drawings.

Acoustic requirements can be communicated through:

• Plans and sections
• Wall and floor types
• Construction details
• Room data sheets
• Door and glazing schedules
• Reflected ceiling plans
• Mechanical and electrical drawings
• Acoustic markups
• Performance specifications
• Acoustic reports
• BIM models and associated data

The important point is that acoustic information is usually distributed across several coordinated documents rather than represented by one universal sound symbol.

Can sound be represented visually?

Sound itself is not visible, but many of the things that influence it can be shown.

An architectural or acoustic drawing may identify:

• The source of a sound
• The room or property being affected
• The route through which sound may travel
• The construction needed to control it
• The required performance of a wall or floor
• Acoustic treatment within a room
• Areas that need particular privacy
• Equipment that may cause noise or vibration
• Survey and monitoring positions
• Acoustic barriers or enclosures

Acoustic modelling can also produce visual outputs such as:

• Noise contour maps
• Colour-coded sound-level plans
• Reverberation maps
• Speech-intelligibility maps
• Façade noise maps
• Sound-system coverage plots
• Three-dimensional room-acoustic models

These visualisations help the project team understand acoustic performance, but they do not normally replace the architectural drawings and specifications needed to construct the building.

Why is there no single symbol for sound?

Sound is not one design element.

An acoustic strategy may need to address:

• Airborne sound between rooms
• Impact noise through floors
• External noise entering the building
• Mechanical-services noise
• Noise leaving the building
• Reverberation within rooms
• Speech intelligibility
• Privacy
• Structure-borne vibration
• Noise affecting neighbouring properties

Each issue requires different information.

A line showing a wall position cannot, by itself, explain:

• How well that wall must reduce sound
• Whether sound can pass through the ceiling void
• What door is needed
• How service penetrations should be sealed
• Whether vibration can travel through the structure
• How the room should perform once occupied

The drawings therefore need to be read alongside schedules, specifications and supporting technical information.

Construction specifications are designed to describe requirements that cannot be fully communicated through a drawing or model. They are normally coordinated with drawings, schedules and other project information.

Where does acoustic information appear?

The exact format depends on the project, design stage, procurement route and the acoustic consultant’s appointment.

The following are common places where acoustic requirements may be recorded.

Plans

Floor plans can communicate important acoustic relationships.

They may show:

• Noisy and quiet areas
• Sensitive rooms
• Plant rooms
• Music or performance spaces
• Meeting rooms requiring privacy
• Acoustic lobbies
• Buffer zones
• Equipment locations
• Nearby noise-sensitive properties
• Proposed barriers
• Survey positions
• Monitoring locations

Plans are particularly useful for acoustic zoning.

For example, locating a store or corridor between a plant room and an occupied space may reduce the level of acoustic construction required.

A plan may also identify where a particular wall, door or ceiling type applies.

Sections

Sections help explain how sound may travel vertically through a building.

They can show:

• Floors between apartments
• Suspended ceilings
• Raised access floors
• Continuous cavities
• Plant above or below occupied rooms
• Façade constructions
• Roof-mounted equipment
• Acoustic screens
• Ventilation openings
• Balconies
• Building orientation relative to noise sources

Sections can reveal potential sound paths that may not be obvious on a plan.

A wall may appear to separate two rooms on the floor plan but stop at a suspended ceiling. Sound could then travel through the shared ceiling void.

Elevations

Elevations can support acoustic design by showing:

• Window and glazing arrangements
• Ventilation openings
• Acoustic louvres
• External plant
• Façade panels
• Balconies
• Screens
• Barriers
• The relationship with nearby buildings
• Areas exposed to road, rail or industrial noise

A façade noise assessment may assign different acoustic requirements to different sides or levels of a building.

This can affect glazing, ventilation and the position of sensitive rooms.

Wall and floor type drawings

Walls and floors are often identified using type references.

For example:

• Wall type W01
• Wall type W02
• Floor type F01
• Ceiling type C01

The detailed construction and required acoustic performance can then be recorded in a schedule, specification or associated detail.

Acoustic information might include:

• A laboratory sound-insulation rating
• A required site performance
• The number and type of board layers
• Cavity construction
• Insulation within the cavity
• Independent frames or linings
• Resilient layers
• Junction requirements
• Sealing requirements
• Restrictions on penetrations

The rating alone is not enough.

The design also needs to consider junctions, workmanship and alternative sound paths around the main element.

Construction details

Detailed drawings are particularly important for acoustic performance.

Sound can pass through relatively small weaknesses, including:

• Gaps around doors
• Unsealed wall edges
• Electrical sockets
• Pipe penetrations
• Ventilation ducts
• Ceiling voids
• Raised floors
• Façade junctions
• Structural connections
• Gaps above partitions

Acoustic details may show:

• How a partition connects to the floor or soffit
• How board layers should overlap
• Where acoustic sealant is required
• How sockets should be positioned
• How ducts should pass through a wall
• How resilient layers should be isolated
• How an acoustic door frame should be sealed
• How a floating floor meets the surrounding wall
• How vibration isolation should be installed

These details need to be coordinated with fire, structural, ventilation and building-services requirements.

A technically strong acoustic detail can still fail if another discipline changes the construction without considering the acoustic effect.

Room data sheets

A room data sheet records the requirements for a particular room or room type.

Acoustic entries might include:

• Background noise target
• Reverberation requirement
• Sound insulation to adjoining rooms
• Door performance
• Speech-privacy requirement
• Acoustic treatment
• Impact-noise requirement
• Building-services criteria
• Speech-intelligibility requirement
• Noise from external sources

Room data sheets can be useful where a building contains many spaces with different needs.

A meeting room, interview room, classroom and plant room should not all be given the same acoustic criteria.

Door schedules

Doors are frequently one of the weakest parts of an acoustic separation.

A door schedule may identify:

• Acoustic rating
• Door construction
• Frame type
• Perimeter seals
• Drop seals
• Threshold details
• Vision panels
• Ironmongery
• Access-control requirements
• Fire performance

The complete doorset matters.

A heavy door leaf may still provide poor acoustic performance if the frame, seals, threshold or glazing have not been designed properly.

The performance also needs to be realistic for the way the door will be used. A high-rated doorset provides limited benefit if it is regularly held open.

Glazing schedules

Glazing requirements may relate to:

• External traffic or aircraft noise
• Commercial or industrial sound
• Privacy between internal rooms
• Studios or performance spaces
• Meeting-room separation
• Noise breaking out from a building

The acoustic performance depends on the complete glazing system, including:

• Glass thickness
• Different pane thicknesses
• Cavity depth
• Laminated layers
• Framing
• Seals
• Trickle vents
• Opening arrangements
• Junctions with the surrounding façade

The design should not consider the glass in isolation.

Reflected ceiling plans

Reflected ceiling plans can show room-acoustic treatment and elements that affect sound transmission.

These may include:

• Acoustic ceiling tiles
• Suspended rafts
• Baffles
• Absorptive ceiling zones
• Reflectors
• Loudspeakers
• Open ceilings
• Bulkheads
• Ventilation grilles
• Lighting
• Ceiling void barriers

Coordination matters because ceiling space is often shared by lighting, ventilation, sprinklers, detectors and other services.

Acoustic treatment also needs to be distributed appropriately. Placing every panel in one convenient corner may not provide the intended result.

Mechanical and electrical drawings

Building-services systems can create and transmit noise through several routes.

Relevant drawings and schedules may identify:

• Fans
• Pumps
• Air-handling units
• Chillers
• Generators
• Transformers
• Lifts
• Ductwork
• Pipework
• Grilles and diffusers
• Attenuators
• Flexible connections
• Vibration isolators
• Plant enclosures
• Acoustic louvres

The acoustic consultant may provide criteria or markups for the M&E team to incorporate.

Information might include:

• Maximum sound levels
• Attenuator requirements
• Duct-lining requirements
• Plant-room constructions
• Equipment-isolation details
• Maximum air velocities
• Locations requiring flexible connections
• External plant noise limits

The final design normally needs coordination between the acoustic consultant, building-services engineer, architect and equipment supplier.

Acoustic specifications

Some acoustic requirements cannot be communicated clearly on drawings alone.

The acoustic specification may describe:

• Required performance criteria
• Applicable standards
• Test methods
• Materials and constructions
• Installation requirements
• Workmanship
• Sealing
• Inspection requirements
• Product-substitution rules
• Testing and commissioning
• Evidence to be provided by contractors

Specifications should be coordinated with the drawings and schedules.

NBS guidance explains that acoustic, thermal and structural requirements can be recorded as performance specifications and developed into more prescriptive requirements as the design progresses.

Acoustic reports

The acoustic report explains the assessment and design reasoning behind the project requirements.

Depending on the project, it may include:

• Noise-survey results
• Planning assessments
• Building-services noise calculations
• Sound-insulation targets
• Room-acoustic criteria
• Acoustic modelling
• Mitigation recommendations
• Construction details
• Testing requirements
• Assumptions
• Design risks

The report should not sit separately from the main project information and then be forgotten.

Its requirements need to be incorporated into the architectural, structural and building-services design.

A statement in an acoustic report has limited value if it does not appear in the information used by the contractor.

Acoustic markups

An acoustic consultant may review the architect’s or engineer’s drawings and issue marked-up versions.

These can identify:

• Required partition upgrades
• Sensitive adjacencies
• Acoustic doors
• Areas requiring absorption
• Plant requiring assessment
• Possible flanking paths
• Junction details needing development
• Survey or test locations
• Information still required

Markups are often useful during design development, but they should not become the only record of the requirement.

Agreed acoustic information should normally be transferred into the coordinated project drawings, schedules, specifications or model.

How are acoustics represented in BIM?

Building Information Modelling allows acoustic requirements to be associated with modelled spaces, systems and construction elements.

The information might be attached to:

• Rooms
• Walls
• Floors
• Doors
• Windows
• Ceilings
• Mechanical equipment
• Ductwork
• Acoustic products

Possible acoustic parameters include:

• Required sound-insulation performance
• Background noise criteria
• Reverberation targets
• Product test data
• Absorption rating
• Door rating
• Plant sound data
• Testing status
• Compliance information

The model does not need to contain every piece of acoustic analysis directly.

It can link or coordinate with:

• Drawings
• Specifications
• Schedules
• Data sheets
• Reports
• Test certificates
• Product information

The UK information-management framework based on the ISO 19650 series is concerned with specifying and delivering the right information across the design, construction, operation and maintenance of an asset.

The value comes from coordination, not from trying to force every requirement into one model view.

What might an acoustic annotation look like?

There is no single annotation format used on every project.

Depending on the design and project standards, an annotation might say:

• Acoustic partition: refer to wall type W05
• Meeting room: enhanced speech privacy required
• Acoustic doorset required
• Absorptive ceiling treatment to this area
• Full-height partition to structural soffit
• Avoid back-to-back sockets
• Seal all service penetrations acoustically
• Provide vibration isolation beneath equipment
• Refer to acoustic report for plant noise limits
• Maintain continuity of resilient floor layer
• Do not bridge isolated construction
• Acoustic barrier height subject to final assessment

Performance figures may also be shown, but they should be used with the correct rating method and supporting specification.

Who is responsible for acoustic drawings?

Responsibility depends on the project appointment and procurement route.

The acoustic consultant may produce:

• Acoustic reports
• Specialist drawings
• Design sketches
• Markups
• Performance schedules
• Calculation outputs
• Acoustic specifications
• Typical details

The architect may then coordinate these requirements into:

• General arrangement drawings
• Wall and floor types
• Room data
• Door schedules
• Reflected ceiling plans
• Construction details
• Specifications

The building-services engineer may incorporate plant, attenuation and vibration requirements into the M&E design.

Specialist contractors may produce fabrication or installation drawings later in the project.

The design team should agree:

• Who defines each acoustic requirement
• Who incorporates it into the coordinated design
• Who checks contractor proposals
• Who approves substitutions
• Who inspects the work
• Who carries out testing

Without clear responsibility, important acoustic requirements can fall between disciplines.

When should acoustic information be added?

Acoustic information should develop alongside the design.

Early design

At the early stages, the focus may be on:

• Site noise
• Building orientation
• Acoustic risks
• Noisy and sensitive adjacencies
• Planning requirements
• Initial room criteria
• Plant locations
• Façade strategy

These decisions can influence the overall layout.

Spatial coordination

As the design develops, the team may establish:

• Wall and floor performance
• Acoustic zoning
• Door requirements
• Ceiling treatment
• Façade constructions
• Ventilation strategy
• Plant noise criteria
• Major junction principles

Technical design

The project information should then develop into coordinated:

• Wall and floor types
• Junction details
• Door schedules
• Glazing schedules
• Room data sheets
• Ceiling plans
• M&E requirements
• Specifications
• Testing requirements

The RIBA Plan of Work describes technical design as the stage where architectural and engineering information is developed and coordinated, leading to construction information and final specifications.

Construction

During construction, acoustic information may need to be reviewed against:

• Product submissions
• Contractor drawings
• Substitutions
• Site conditions
• Workmanship
• Design changes
• Service penetrations
• Inspection findings

A seemingly small substitution can affect acoustic performance.

For example, changing a door, ceiling system, wall board or vibration mount should be reviewed against the original requirement rather than accepted as visually equivalent.

Completion

Testing and commissioning can confirm whether particular requirements have been achieved.

This may include:

• Airborne sound-insulation testing
• Impact sound testing
• Room-acoustic measurement
• Building-services noise testing
• Plant noise verification
• Speech-intelligibility testing
• Vibration measurement

The results may be recorded in test reports, commissioning information and the final building information.

Which acoustic requirements are covered by building regulations?

There is no single building-regulation requirement covering every aspect of architectural acoustics.

In England, Approved Document E provides guidance on resistance to the passage of sound for:

• Dwelling-houses
• Flats
• Rooms for residential purposes
• Schools

It does not provide general acoustic requirements for every office, restaurant, hospital or public building.

Other acoustic requirements may arise from:

• Planning conditions
• Local authority guidance
• Client briefs
• Lease requirements
• BREEAM
• Education or healthcare guidance
• Industry standards
• Building-services criteria
• Licensing conditions
• Contractual requirements

BS 8233:2014 currently provides general guidance on sound insulation and noise reduction for new buildings and certain refurbishment or change-of-use projects. It includes external noise, building-services noise and room acoustics for non-specialist situations.

The relevant requirement should be identified for the particular building and use.

Does every architectural project need acoustic drawings?

Not every project needs a separate set of drawings labelled “acoustic”.

A smaller project may be adequately supported through:

• Notes on the architect’s drawings
• A short acoustic report
• Wall or door schedules
• Specification clauses
• A small number of details

A larger or more complex project may need:

• Dedicated acoustic drawings
• Detailed markups
• Room-by-room criteria
• Acoustic models
• Noise contour plans
• Extensive coordination
• Site inspections
• Testing schedules

The level of information should reflect:

• Project complexity
• Acoustic risk
• Regulatory requirements
• Building use
• Procurement route
• The design team’s responsibilities

The aim is not to create more drawings than necessary. It is to make sure the people designing and constructing the building have clear, coordinated information.

Common problems with acoustic design information

Typical problems include:

• Acoustic advice being issued too late
• Requirements remaining only in a report
• Drawings and specifications contradicting each other
• Wall ratings being shown without junction details
• Acoustic doors being omitted from schedules
• Service penetrations not being coordinated
• Partitions stopping at suspended ceilings
• Plant noise limits not reaching equipment suppliers
• Substitutions being accepted without acoustic review
• Product ratings being copied without checking test conditions
• Acoustic treatment being moved for visual reasons
• Testing requirements not being included in the contract
• No one being responsible for coordinating acoustic information

These issues are less likely when the acoustic consultant is involved early and the information is updated as the design develops.

Why architects and acoustic consultants need to work together

Architects shape the layout, geometry, envelope, finishes and experience of a building.

Acoustic consultants help predict how those decisions will affect:

• Noise
• Privacy
• Communication
• Comfort
• Reverberation
• Building-services sound
• Neighbouring properties

The two disciplines overlap, but their roles are not identical.

The acoustic consultant should not work separately and simply deliver a report at the end. The architect should not be expected to resolve specialist acoustic questions without suitable input.

The strongest results come from integrating acoustic advice into the coordinated design.

Talk to auricl about acoustic design information

If you are designing a building, refurbishment or fit-out, we can help translate the acoustic requirements into practical information for the wider project team.

This may include acoustic reports, drawing reviews, markups, performance criteria, construction advice and testing.

Tell us what you are working on and which stage the project has reached. We’ll suggest the right next step.