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Noise is one of the most common frustrations in modern living, whether you own a home, live in a flat, or manage a residential development project. Understanding how sound travels through buildings is essential, not just for peace and comfort but also for compliance with Part E Building Regulations, which govern sound insulation in the UK.
Two types of sound dominate the conversation: airborne noise and impact noise. While both can disturb daily life, they behave differently, require different solutions, and are tested separately in sound insulation assessments. For homeowners, landlords, and developers, recognising the difference is the first step to solving noise issues effectively.
Need professional help? At Falcon Energy, we provide accredited sound insulation testing services for both airborne and impact noise, ensuring compliance and reducing unwanted sound transfer in your property. Call us on 01403 253439 for a free, no-obligation quote.
Why the Distinction Matters
When a property is poorly insulated against sound, occupants may struggle with sleep, privacy, and day-to-day comfort. For developers, weak sound performance can cause projects to fail mandatory tests, delaying completion and creating costly remedial work. Knowing whether the problem lies with airborne or impact sound allows you to target the right solutions, ensuring compliance and better living standards.
What Does Airborne Sound Mean?
Airborne sound refers to noise that travels through the air before striking a surface. Common examples include:
- Voices from the next room
- Music from a neighbour’s stereo
- The sound of traffic outside
Once airborne noise reaches a wall, ceiling, or floor, it vibrates the structure, allowing some of that sound energy to pass through into the next space.
Because airborne noise spreads freely in all directions, it is often the cause of complaints in semi-detached houses and terraced properties, where thin party walls can make every conversation, radio, or barking dog seem amplified. Airborne sound can find its way through even the smallest gaps or cracks, much like water seeping through tiny openings.
What is Impact Sound?
Impact sound, by contrast, occurs when an object makes direct contact with a building surface, producing vibrations that travel through the structure itself. This includes:
- Footsteps on a timber floor
- Chairs scraping across tiles
- Doors slamming are all familiar examples
Unlike airborne noise, impact sound doesn’t start in the air. It begins as a physical vibration and then radiates as noise into surrounding rooms. This is why people often complain about noisy upstairs neighbours. The sound of walking or dropping items transfers directly down through the ceiling structure.
Before exploring soundproofing solutions, it’s worth understanding how sound waves move through a property. Knowing where noise originates and how it spreads helps you target the right soundproofing solutions, avoiding wasted time and money.
Noise enters existing homes in three main ways:
- Airborne noise, like voices or TV, can travel through walls, doors, and windows.
- Impact noise from footsteps or furniture through floors and ceilings.
- Flanking transmission, where sound bypasses barriers via ducts, gaps, or other indirect paths.
Different wall types also influence performance. Brick walls provide density but may allow sound to leak through cracks. Internal stud walls built with single plasterboard are lightweight and prone to noise transfer. Party walls in conversions, flats, or semi-detached homes often carry both airborne and impact noise if not properly insulated.
These challenges can be addressed with targeted approaches. Adding extra plasterboard, incorporating acoustic insulation into a stud frame, or installing slim, high-performance wall systems are all proven ways to reduce sound transmission while keeping room space loss to a minimum.
Typical Sources of Airborne Noise and Impact Noise
Airborne noise
Airborne noise comes from sounds that travel through the air before penetrating walls, ceilings, or floors. It is common in homes with thin construction or poor sealing. Typical sources include:
- Conversations and voices carrying through walls
- Televisions, radios, and music systems
- External noise, such as traffic or barking dogs
To reduce airborne sound, the focus is on adding mass and improving airtightness. This can be achieved by:
- Adding layers of dense plasterboard
- Sealing gaps with acoustic sealant
- Installing insulation within the wall or floor cavities
- Upgrading weak points like windows and doors with acoustic glazing or solid-core doors
Impact noise
Impact noise occurs when objects strike a surface, creating vibrations that travel through the building’s structure. It is especially disruptive in flats and apartments. Typical sources include:
- Footsteps on hard floors
- Children running or jumping
- Appliances such as washing machines or dryers vibrating against the floor
- Furniture being moved or dropped
The key to reducing impact noise is to absorb or break the path of vibration. Common solutions are:
- Carpets, acoustic underlays, or mats to soften impacts
- Floating floors that separate floor surfaces from the structure
- Resilient bars to decouple ceilings from joists
Airborne vs Impact Noise: The Key Differences
Although both airborne and impact sound are disruptive, the way they behave in buildings is distinct. The comparison below highlights the main differences.
| Aspect | Airborne Noise | Impact Noise |
|---|---|---|
| How it starts | Travels through the air before hitting a barrier | Starts as vibrations from direct surface contact |
| Common examples | Speech, TV, music, barking dogs | Footsteps, furniture being moved, dropped objects |
| How it spreads | Through air, then penetrates walls/floors | Through the building’s structure, as vibration |
| Most common complaints | Conversations through walls, loud televisions | Noisy upstairs neighbours, slamming doors |
| Best solutions | Increase wall/floor mass, improve airtightness | Install carpets, resilient underlays, floating floors |
Does Sound Travel Up or Down?
One of the most common questions about noise is whether it “travels upwards” or “downwards.” The reality is that sound waves move in all directions. Airborne noise can easily rise, fall, or spread sideways depending on weak points in the structure. Impact noise, however, is most noticeable below its source, since vibrations travel strongly downwards through floors and ceilings.
This is why a TV downstairs may be faintly heard above, but footsteps upstairs feel much louder below. Both scenarios stem from different sound paths, which is why addressing noise requires an understanding of both types.
Why UK Homes Struggle with Noise
Many British homes, particularly those built before modern noise regulations were introduced, lack adequate soundproofing. Timber floors, lightweight stud walls, and minimal acoustic insulation leave plenty of paths for sound to travel. Even newer properties can fail sound tests if they are not carefully designed and constructed.
For homeowners, this means that both everyday life and property value can be affected. For developers, poor sound performance risks non-compliance with Part E and potential disputes with buyers or tenants.
Flats vs Houses: Which Suffers More?
In flats, impact noise tends to be the most dominant. Every step from an upstairs neighbour can be heard below, especially if hard flooring has been installed without proper underlay. In semi-detached or terraced houses, airborne noise is often a greater concern, particularly through party walls. Detached houses are less affected by neighbour noise but often suffer from external airborne sound such as traffic.
The Role of Sound Insulation Testing
To separate airborne and impact sound problems and measure how well a property performs, professional sound insulation testing is essential. This testing is used to verify whether a building meets the required sound insulation standards. Using specialist equipment, accredited testers measure airborne noise through walls and floors, and impact noise from floors and ceilings, to ensure buildings meet UK standards.
Passing these tests is mandatory for most new builds and conversions, and failing them can result in expensive remedial works, from adding insulation to rebuilding floors.
Compliance with Part E Building Regulations
In the UK, Approved Document E requires that both airborne and impact sound insulation meet minimum standards between dwellings. Without passing sound insulation testing, new builds and conversions cannot be signed off. For developers, this means soundproofing is not optional but essential. For homeowners, it provides reassurance that a property meets modern standards of comfort and privacy.
To better understand the regulations that set the minimum standards for noise control in UK buildings, explore our in-depth guide on Part E Building Regulations and Soundproofing. It explains what Part E covers, the required sound insulation values, and practical steps developers and homeowners can take to achieve compliance.
The Cost of Getting it Wrong
Attempting to solve noise problems without identifying whether they are airborne or impact-related can lead to wasted money. Adding carpets won’t stop your neighbour’s television, and sealing a wall won’t silence footsteps overhead. This is why professional testing and advice are critical before investing in soundproofing measures.
Investing in proper sound insulation brings multiple benefits. For homeowners, it improves comfort, privacy, and even property value. For developers, it ensures compliance, avoids costly remedial work, and builds confidence among buyers. A quieter home isn’t just a more pleasant place to live, it’s also a more marketable one.
Soundproofing and Health
Soundproofing isn’t just about comfort; it plays a vital role in protecting our health and well-being. Exposure to airborne noise, whether from traffic, neighbours, or other sources, can lead to stress, anxiety, and even sleep disturbances. Over time, these issues can affect both physical and mental health, making it more difficult to relax, concentrate, or recover from daily stresses.
By investing in soundproofing products and materials, you can create a healthier environment at home, in schools, or at the workplace. For example, using soundproofing materials with high sound absorption properties can reduce airborne noise and reverberation, making rooms quieter and more comfortable. This is especially important in environments where people need to focus or rest, such as bedrooms, classrooms, or offices.
Effective soundproofing can also help prevent hearing loss and other noise-related health problems by reducing the overall impact of unwanted sound. Ultimately, creating a peaceful environment with the right soundproofing products is a proactive step towards better health and well-being for everyone who shares the space.
Summary
Understanding the difference between airborne and impact sound is the foundation of effective noise control. Both can make life uncomfortable, but by recognising the type of sound you’re dealing with, you can choose the right solution. For developers, compliance with Part E regulations makes this knowledge essential. For homeowners, it ensures peace, privacy, and a better quality of life.
Book sound insulation testing with Falcon Energy
At Falcon Energy, we provide professional sound insulation testing to measure and address both airborne and impact sound in residential properties. If you’re experiencing noise problems or planning a project, please call us on 01403 253439 or contact us online to arrange your test.
Airborne vs Impact Sound FAQs
Does sound travel up or down?
Sound waves move in all directions. Airborne noise spreads freely, while impact noise is most strongly felt downwards through ceilings.
What does airborne mean in sound insulation?
Airborne sound refers to noise that travels through the air, such as speech, music, or traffic, before striking a barrier like a wall or window.
What is impact noise in buildings?
Impact noise occurs when something physically strikes a building surface, such as footsteps or moving furniture, and the vibration travels through the structure.
Which is harder to block: airborne or impact noise?
Impact noise is often more challenging to manage because it travels through solid structures, but both require targeted solutions.
Do I need sound insulation testing?
If you are building or converting a property in the UK, testing is a legal requirement under Part E. Homeowners experiencing noise problems can also benefit from testing to identify weak points and invest in effective solutions.