Principles, Elements and Strategies
Introduction
Landscape architecture is usually experienced visually, but landscapes are also acoustic environments.
The sound of traffic, pedestrians, birds, wind, rain, flowing water, mechanical equipment and human activity contributes to how a park, garden, plaza, campus or public open space is perceived.
For this reason, acoustic design in landscape architecture is not limited to constructing a noise barrier. It involves understanding the existing acoustic environment and deliberately arranging landform, vegetation, water, buildings, paths, activity zones and other landscape elements to reduce unwanted sound and support desirable sounds.
This broader approach is commonly described through the concept of soundscape. ISO 12913-1 defines soundscape around the acoustic environment as it is perceived, experienced and/or understood by people in context. The standard provides a conceptual framework for soundscape planning, design and management. [1]
A successful landscape acoustic strategy therefore asks two questions:
- How can unwanted sound be reduced or controlled?
- How can desirable sounds and positive auditory experiences be supported?
The second question is what distinguishes soundscape design from conventional noise control.
What Is Acoustic Design in Landscape Architecture?
Acoustic design in landscape architecture is the deliberate planning of outdoor spaces to control unwanted noise, support desirable sounds and improve people’s experience of the acoustic environment.
It combines principles of acoustics, landscape planning, environmental design and human perception.
A landscape architect may use:
- Site zoning
- Building placement
- Landform and berms
- Walls and acoustic barriers
- Vegetation
- Water features
- Ground surfaces
- Spatial enclosure
- Circulation planning
- Activity separation
- Distance from noise sources
- Soundscape mapping
- Quiet zones
- Sound-producing landscape elements
The objective is not necessarily to make a site silent.
In many situations, complete silence would be neither realistic nor desirable. A park may contain children playing, birds singing, people talking, water flowing and leaves moving in the wind.
The design objective is instead to create an appropriate acoustic environment for the intended activity and character of the place.
Acoustic Environment vs Soundscape
These terms are related but should not be treated as identical.
| Term | Meaning | Landscape application |
|---|---|---|
| Acoustic environment | The physical collection of sounds present in an environment | Traffic, voices, machinery, birds, water and wind |
| Noise | Sound that is unwanted or disruptive in a particular context | Traffic disturbing a meditation garden |
| Soundscape | The acoustic environment as perceived and experienced by people in context | The overall auditory experience of a park |
| Acoustic design | Deliberate design intervention affecting sound | Berms, zoning, barriers and water |
| Soundscape design | Designing the acoustic experience, including desirable sounds | Protecting natural sounds and introducing appropriate water sounds |
ISO 12913 provides the international framework for understanding soundscape, while research in landscape architecture has increasingly examined how sound can become an active design parameter rather than simply a problem to suppress. [1][4]
Why Is Acoustic Design Important in Landscape Architecture?
Outdoor acoustic conditions influence how people perceive and use spaces.
The World Health Organization identifies environmental noise as an important environmental health issue and associates excessive exposure with effects including annoyance, sleep disturbance and other health impacts. Its environmental noise guidelines address sources such as road traffic, railways, aircraft, wind turbines and leisure activities. [5]
Landscape architecture cannot solve every environmental noise problem, but spatial design can influence exposure and perception.
Acoustic design can help to:
- Protect quiet recreational areas
- Separate noisy and quiet activities
- Reduce exposure to traffic noise
- Improve the experience of public parks
- Support outdoor learning environments
- Protect sensitive ecological areas
- Create restorative spaces
- Strengthen the identity of a place
- Enhance sensory experience
- Integrate noise mitigation with landscape character
Research on urban parks has also shown that perceived soundscape quality is influenced by more than measured sound level alone. Natural features, vegetation, expectations and the overall tranquillity of the environment can affect people’s assessment of a place. [2]
Principles of Acoustic Design in Landscape Architecture
1. Understand the Existing Soundscape
Acoustic design should begin with site analysis.
Before introducing a barrier, fountain or planting belt, the designer should understand what already exists.
Identify:
- Major noise sources
- Natural sound sources
- Human activity
- Time-dependent sound
- Seasonal variations
- Sensitive receptors
- Quiet areas
- Noise corridors
- Sound propagation paths
- Existing barriers
- Reflective surfaces
- Potential acoustic opportunities
A road may produce continuous noise, while a playground produces intermittent but locally intense sound.
A railway may produce short-duration high-level events, while an HVAC plant may create a continuous mechanical background.
These sources require different design responses.
2. Identify Noise Sources and Receivers
A useful acoustic site analysis considers three basic components:
Source → Path → Receiver
For example:
Road traffic → open ground → park user
A landscape intervention can act on each part of this relationship.
Source
Where possible, reduce noise at its origin.
Path
Interrupt or modify the transmission path using:
- Distance
- Berms
- Walls
- Barriers
- Landform
- Buildings
- Dense site structures
Receiver
Protect the sensitive space or user by locating it appropriately.
For example, a children’s reading garden should not automatically be placed beside the loudest road edge simply because that area is visually attractive.
3. Use Spatial Zoning
One of the most effective landscape strategies is often planning rather than construction.
Instead of placing every activity uniformly across a site, divide the landscape according to acoustic requirements.
Example acoustic zoning
| Zone | Acoustic requirement | Possible uses |
|---|---|---|
| High-noise zone | Noise-tolerant | Parking, service areas, active recreation |
| Moderate-noise zone | Mixed acoustic environment | Walkways, plazas, cafés |
| Low-noise zone | Relatively protected | Gardens, seating, reading |
| Quiet zone | High acoustic sensitivity | Meditation, contemplation, ecological observation |
This approach can reduce dependence on large engineered barriers.
Scottish Government guidance similarly identifies spatial separation and appropriate placement of activities as an important way of limiting noise exposure. [6]
4. Increase Distance from Noise Sources
Sound generally becomes weaker as it travels away from a source, although the actual reduction depends on source characteristics, geometry, ground conditions, reflections and atmospheric conditions.
Landscape planning can therefore use distance as an acoustic design tool.
For example:
Road → service zone → planting/berm → circulation → quiet garden
rather than:
Road → quiet garden
This is particularly useful when planning large parks, campuses and institutional landscapes.
5. Use Landform as an Acoustic Element
Landform is one of the most powerful ways to combine acoustic and landscape design.
Earth berms can interrupt the direct line of sight between a source and receiver and increase the acoustic path length.
Possible forms include:
- Earth berms
- Raised landscape edges
- Terraces
- Depressed activity areas
- Contoured terrain
- Sunken gardens
- Retaining structures
The advantage of a berm is that it can perform multiple functions.
It can simultaneously provide:
- Noise screening
- Visual screening
- Planting space
- Ecological habitat
- Stormwater opportunities
- Spatial definition
- Topographic interest
Transport Scotland documentation demonstrates how earth bunds and fencing can be integrated into landscape and noise mitigation design rather than treated as completely separate systems. [7]
Important limitation
A berm is not automatically an effective acoustic barrier simply because it is large.
Its geometry, height, location, continuity and relationship to the source and receiver all matter.
Detailed projects should therefore involve an acoustic consultant where regulatory or performance requirements apply.
6. Use Acoustic Barriers Carefully
Acoustic walls and fences can provide significant noise reduction when properly designed and located.
Possible materials include:
- Masonry
- Concrete
- Timber systems
- Composite acoustic panels
- Earth-and-wall combinations
- Specialized acoustic fencing
A barrier should be considered as part of the landscape rather than as an isolated technical object.
Design considerations
Consider:
- Barrier height
- Barrier continuity
- Position relative to source
- Position relative to receiver
- Gaps
- Reflections
- Visual impact
- Maintenance
- Safety
- Drainage
- Material durability
- Landscape integration
The Scottish Government’s technical guidance identifies purpose-designed barriers as one potential component of noise mitigation, alongside source reduction and protection of sensitive areas. [6]
7. Understand the Role of Vegetation
Trees and planting are often presented as simple “natural sound barriers.”
This needs to be explained carefully.
A narrow line of trees by itself should not be assumed to provide substantial traffic-noise reduction.
Vegetation can influence acoustic conditions through:
- Scattering
- Absorption by foliage and branches
- Ground-softening effects
- Visual screening
- Perceptual masking
- Wind-generated natural sound
- Creation of psychological separation
The physical acoustic effect of planting depends strongly on density, depth, height, species characteristics, ground conditions and frequency.
A major landscape advantage is therefore often the combined effect of planting, landform and spatial separation, rather than trees acting alone.
Government guidance also notes that dense planting can contribute visual screening and some natural masking, while acoustic experts should be involved where performance is important. [8]
Better planting strategy
Instead of:
Road → thin row of trees → park
consider:
Road → berm → dense multi-layer planting → setback → park
The planting then becomes part of a larger acoustic landscape system.
8. Design with Ground Surfaces
Ground materials influence acoustic conditions.
Hard surfaces such as:
- Concrete
- Stone
- Dense paving
can create more reflective environments.
Softer ground conditions such as:
- Soil
- Planting beds
- Grass
- Some porous landscape surfaces
can contribute to greater acoustic absorption under appropriate conditions.
Surface selection should therefore be coordinated with:
- Pedestrian movement
- Drainage
- Accessibility
- Maintenance
- Climate
- Durability
- Acoustic objectives
Acoustic performance should never be considered independently of the functional requirements of the landscape.
9. Use Water as a Soundscape Element
Water is one of the most interesting tools in soundscape design.
Examples include:
- Fountains
- Cascades
- Streams
- Water walls
- Jets
- Bubbling water
- Rills
- Interactive water features
Water can introduce a desirable sound that changes the auditory character of a space.
However, water does not automatically improve a soundscape.
Research has demonstrated that the acoustic and visual characteristics of water features influence people’s perception, and field studies have found that some water features can improve soundscape assessments while others can produce less positive results. [9][10]
A 2024 study examined water features including fountains, cascades, waterfalls and natural streams and used sound mapping to identify zones where water sounds could become dominant relative to road traffic. The effectiveness varied according to traffic-noise level and water-feature type. [11]
Therefore:
A water feature should be acoustically designed, not simply added for decoration.
10. Introduce Positive Sounds
Soundscape design is not only about reducing unwanted sound.
Landscape architects can deliberately strengthen desirable acoustic experiences.
Potential sources include:
- Water
- Wind through vegetation
- Birds
- Natural habitat
- Footsteps
- Carefully designed interactive elements
- Cultural or artistic sound installations
The objective should be appropriate to the site’s identity.
A botanical garden may benefit from emphasizing natural sounds.
A civic plaza may intentionally support social sounds.
A memorial garden may require greater acoustic calm.
An educational landscape may use sound as an interpretive medium.
11. Protect Quiet Areas
A quiet landscape does not necessarily mean an absolutely silent landscape.
The idea is to provide places where users can experience comparatively low disturbance or a particular desired soundscape.
Potential quiet spaces include:
- Meditation gardens
- Therapeutic gardens
- Reading gardens
- Memorial landscapes
- Nature reserves
- University courtyards
- Healing landscapes
- Retreat gardens
- Ecological observation areas
Research on urban quiet zones indicates that soundscape assessment and perceived recreational suitability cannot always be reduced to a single measured noise value. [12]
The designer should therefore consider both:
Acoustic measurements + human perception
12. Consider Visual-Acoustic Relationships
Sound and vision interact.
A visible fountain may be perceived differently from an unseen recording of water.
Similarly, seeing a road can reinforce awareness of traffic noise, while a visually screened road may change the perceived relationship between the landscape and the source.
This means acoustic design should be coordinated with:
- Views
- Screening
- Vegetation
- Landform
- Spatial enclosure
- Materiality
- Lighting
- Circulation
The acoustic experience should reinforce the intended visual and spatial character.
13. Soundscape Mapping
Soundscape mapping is a useful tool for landscape architects.
A site can be surveyed and represented through a combination of:
- Sound levels
- Sound sources
- Time
- Location
- User perception
- Sound type
- Activity
- Environmental conditions
ASLA has documented landscape soundscape mapping using GIS-based approaches to understand acoustic conditions and inform landscape planning. [13]
A simplified sound map might identify:
| Sound condition | Site interpretation |
|---|---|
| Continuous traffic | Noise exposure corridor |
| Intermittent traffic | Variable acoustic edge |
| Human activity | Social sound zone |
| Birds/natural sounds | Ecological soundscape |
| Water | Potential positive sound source |
| Mechanical equipment | Localized unwanted source |
| Low activity | Potential quiet zone |
14. Conduct Soundwalks
A soundwalk is a structured method of experiencing and documenting the acoustic character of a site while moving through it.
A soundwalk can record:
- What is heard
- Where it is heard
- How loud it appears
- Whether it is pleasant or unpleasant
- Whether it is expected
- Whether it supports the activity
- How the sound changes through space
Soundwalks are particularly useful because soundscape is fundamentally connected with perception and context.
For students, a soundwalk can be one of the simplest ways to understand the acoustic dimension of landscape architecture.
15. Consider Time and Season
A landscape does not have one fixed soundscape.
Its acoustic environment changes according to:
- Morning
- Afternoon
- Evening
- Night
- Weekdays
- Weekends
- Festivals
- School hours
- Traffic peaks
- Seasonal vegetation
- Rain
- Wind
- Wildlife activity
For example, a university campus may have a very different acoustic character during examination periods compared with a normal weekday.
Similarly, a park may experience increased traffic noise during commuting hours.
Acoustic analysis should therefore consider the time dimension of landscape.
Acoustic Elements Used in Landscape Architecture
| Element | Primary acoustic role | Other landscape role |
|---|---|---|
| Berm | Blocks/directs sound | Landform and visual screening |
| Acoustic wall | Reduces sound transmission | Boundary and enclosure |
| Dense planting | Supports screening and perceptual masking | Habitat and shade |
| Trees | Scattering, screening and natural sound | Canopy and microclimate |
| Water feature | Introduces/masks sound | Cooling, identity and visual focus |
| Building mass | Can block or reflect sound | Program and enclosure |
| Depressed garden | Can reduce direct exposure | Spatial character |
| Soft ground | Can reduce reflections | Planting surface |
| Spatial setback | Reduces exposure through distance | Creates transition zone |
| Activity zoning | Separates incompatible uses | Functional planning |
Acoustic Design Process for Landscape Architecture
A practical workflow can be organized into eight stages.
Stage 1 — Site Reconnaissance
Identify:
- Roads
- Railways
- Airports
- Industrial sources
- Mechanical equipment
- Commercial activity
- Pedestrian activity
- Natural sound sources
Stage 2 — Acoustic Survey
Record sound conditions at representative locations and times.
Where necessary, use qualified acoustic professionals and appropriate measurement standards.
Stage 3 — Soundscape Mapping
Map both:
- Quantitative acoustic information
- Qualitative perception
Stage 4 — Acoustic Zoning
Identify areas requiring:
- Protection
- Mitigation
- Neutral treatment
- Active soundscape enhancement
Stage 5 — Source-Path-Receiver Analysis
Determine whether the best intervention should address:
- Source
- Transmission path
- Receiver
- Or a combination
Stage 6 — Landscape Intervention
Develop:
- Berms
- Barriers
- Planting
- Water
- Buildings
- Setbacks
- Spatial zoning
- Surface strategies
Stage 7 — Evaluation
Check whether the proposed design actually improves the intended acoustic condition.
Stage 8 — Post-Occupancy Review
Where appropriate, evaluate the completed landscape through:
- Measurements
- User surveys
- Soundwalks
- Observation
- Maintenance review
This creates a feedback loop between design intention and actual user experience.
Acoustic Design for Different Landscape Types
Urban Parks
Typical problems:
- Road traffic
- Public transport
- Pedestrian activity
- Events
- Commercial surroundings
Strategies:
- Protect interior quiet zones
- Use landform
- Place active uses toward noisy edges
- Introduce appropriate natural sounds
- Preserve existing natural sound sources
Educational Campuses
Consider:
- Outdoor classrooms
- Reading areas
- Sports fields
- Cafeterias
- Assembly spaces
Noisy and quiet functions should be zoned carefully.
Healthcare Landscapes
Therapeutic gardens may require greater control of:
- Traffic noise
- Mechanical noise
- Crowd noise
- Service activity
Acoustic comfort can become part of a wider therapeutic landscape strategy.
Residential Landscapes
Important sources include:
- Road traffic
- Neighbouring properties
- HVAC equipment
- Parking
- Play areas
Planning should separate noise-sensitive private areas from major sources.
Commercial Plazas
Some sound is desirable.
Conversation, movement and activity can contribute to place identity.
The objective is therefore not maximum quietness but an appropriate balance between activity and acoustic comfort.
Acoustic Design and Accessibility
Acoustic design should also consider users with different sensory needs.
People who are deaf or hard of hearing may rely on visual information, spatial awareness, lighting and clear sightlines.
For users with sensory sensitivities, excessive or unpredictable noise can affect comfort and usability.
Landscape design should therefore coordinate acoustics with:
- Visual connectivity
- Lighting
- Wayfinding
- Seating
- Movement
- Accessibility
- Safety
- Sensory diversity
ASLA’s discussion of DeafSpace and landscape design illustrates how acoustics can be considered alongside other sensory and spatial requirements rather than as an isolated technical issue. [14]
Acoustic Design and Ecology
The acoustic environment also matters beyond human comfort.
Natural sound can form part of ecological systems.
Bird calls, insect sounds, amphibian calls and other biological sounds can communicate information about habitat and species interactions.
Anthropogenic noise may interfere with these acoustic signals.
Landscape soundscape research therefore increasingly considers the relationship between:
human sound + natural sound + habitat + ecological processes
Recent landscape design research and student work have explored buffers, topography, zoning and planting as ways of considering acoustic conditions for both people and ecosystems. [15]
This suggests an important shift:
Landscape acoustics can be considered as both a human-comfort issue and an ecological design issue.
Common Mistakes in Landscape Acoustic Design
Mistake 1: Assuming Trees Solve Noise Problems
A thin row of trees is not equivalent to a purpose-designed acoustic barrier.
Mistake 2: Designing Only for Decibels
Measured sound level is important, but soundscape also involves perception and context.
Mistake 3: Adding Water Without Testing
A fountain can change the acoustic environment, but not necessarily in the desired direction.
Mistake 4: Ignoring Noise at the Planning Stage
Trying to fix an acoustic problem after the site layout is finalized can be much more difficult.
Mistake 5: Treating Acoustic Barriers as Separate from Landscape Design
A technically effective barrier can still create a poor landscape if it produces visual, spatial or maintenance problems.
Mistake 6: Ignoring Time
A site that is quiet at 10:00 AM may be noisy during the evening or peak traffic period.
Mistake 7: Confusing Quiet with Good
A soundscape with low measured noise is not automatically the best acoustic experience for every activity.
Mistake 8: Ignoring Maintenance
Water pumps, mechanical equipment, fences, gates and planting conditions can change the acoustic character of a landscape over time.
Advantages of Acoustic Design in Landscape Architecture
A coordinated acoustic strategy can:
- Improve outdoor comfort
- Reduce exposure to unwanted noise
- Protect quiet areas
- Improve recreational environments
- Strengthen sensory experience
- Support placemaking
- Integrate environmental design
- Enhance ecological awareness
- Improve separation between incompatible activities
- Create more meaningful public spaces
Limitations and Challenges
Acoustic landscape design also has limitations.
1. Landscape alone cannot solve every noise problem
Major transportation or industrial noise may require engineering and regulatory measures.
2. Acoustic performance is site-specific
A strategy that works in one location may not produce the same result elsewhere.
3. Perception varies
Different users may respond differently to the same sound.
4. Vegetation is frequently overestimated
Planting should not be presented as a substitute for a properly engineered barrier where substantial attenuation is required.
5. Water requires energy and maintenance
Pumps, filtration, water quality and operational costs must be considered.
6. Barriers have visual consequences
Large barriers can create enclosure, safety and visual-impact issues.
7. Soundscape changes over time
Weather, vegetation, activity and urban development continually alter acoustic conditions.
A Simple Acoustic Design Checklist for Architecture Students
Before finalizing a landscape plan, ask:
Site
- Where are the major noise sources?
- Where are the naturally quiet areas?
- How does sound vary throughout the day?
Planning
- Are noisy and quiet functions appropriately separated?
- Can distance reduce exposure?
- Can buildings or landform interrupt sound paths?
Landscape
- Can berms improve the acoustic condition?
- Can planting contribute to screening or masking?
- Are ground surfaces appropriate?
Soundscape
- Which sounds should be reduced?
- Which sounds should be preserved?
- Which sounds could be introduced?
Users
- Who will use the space?
- What acoustic environment does the activity require?
- Are sensory and accessibility requirements considered?
Evaluation
- Has the site been measured or listened to?
- Has the proposed intervention been evaluated?
- Is specialist acoustic modelling required?
Featured Snippet: What Is Acoustic Design in Landscape Architecture?
Acoustic design in landscape architecture is the planning of outdoor spaces to control unwanted noise and improve the acoustic experience of users. It uses site planning, distance, landform, barriers, vegetation, water, spatial zoning and soundscape strategies to create appropriate acoustic conditions for parks, gardens, campuses, plazas and other landscapes.
Featured Snippet: Do Trees Reduce Noise?
Trees and vegetation can contribute to acoustic screening, scattering and perceptual masking, but a narrow planting strip should not automatically be treated as an effective noise barrier. The acoustic benefit depends on vegetation density, depth, height, ground conditions and the relationship between the source and receiver. For significant noise-control requirements, engineered solutions and acoustic assessment may be necessary.
Featured Snippet: What Is Soundscape Design?
Soundscape design is the deliberate planning of the acoustic environment as it is experienced by people in context. Instead of focusing only on reducing noise levels, it considers the identity, quality, sources, perception and spatial distribution of sounds and can include both the reduction of unwanted sounds and enhancement of desirable sounds.
Conclusion
Acoustic design in landscape architecture expands the way designers understand outdoor space.
A landscape is not only a composition of forms, materials, vegetation and views. It is also an acoustic environment that changes with movement, weather, activity, time and season.
The most effective approach is therefore not simply to “block noise.”
Instead, landscape architects should:
understand the soundscape → identify sources → analyse pathways → zone activities → use distance and landform → integrate barriers and planting → introduce appropriate sounds → protect quiet areas → evaluate user perception.
The result can be a landscape that is not only visually successful but also acoustically meaningful.
The central principle is simple:
Design the sounds of a landscape as deliberately as you design its spaces.
For students, this provides another method of reading and analysing a site. For practicing architects and landscape architects, it provides an opportunity to integrate acoustics with planning, environmental design, accessibility, ecology and human experience.
Sound should therefore be treated not merely as something that occurs after a landscape has been designed, but as one of the environmental conditions through which the landscape is experienced.