News

Mineral wool is a widely used open cell insulation material created by melting rock or industrial slag and spinning it into fine, wool-like fibres.

The term ‘Open Cell Cavity Insulation’ is another phrase used to typically describe these types of materials.

Although quite a bulky and thick material, it is valued for its thermal insulation, soundproofing abilities, and resistance to fire, making it suitable for use in cavities within building construction, pipe insulation, and various other industrial applications.

It’s one of the most widely used and effective forms of insulation found in modern construction, particularly in homes and buildings that require not just thermal efficiency, but also sound control.

While it’s often thought of as a general-purpose insulator, mineral wool plays a crucial role in acoustic absorption, especially when installed in framed cavity walls made from timber or aluminium stud, as well as between floor joist systems.

History of Mineral Wool

Mineral wool dates back to the late 19th century, when it was first discovered in volcanic areas as a natural by-product of lava cooling rapidly in strong wind.

This formed thin, wool-like fibres, hence the name.

The industrial production of mineral wool began shortly thereafter, with manufacturers realising that molten rock or slag could be spun into fibres mechanically, creating an insulating material that was lightweight, fire-resistant, and excellent at trapping air.

Over time, the formulation was refined to improve its consistency, density, and suitability for specific applications, including acoustic insulation.

How Does It Work?

Mineral wool works by trapping air within a dense matrix of fibrous material.

When used for thermal insulation, it slows down the movement of warm air through walls, ceilings and floors, relying predominantly on its own depth of material to achieve thermal resistance and a slowing of thermal creep.

Thermal Conductivity values can vary from around the 0.038W/mK to 0.032W/mK which is applied in thicknesses usually from 25mm, 50mm 75mm or 100mm.

When needing to arrest and eliminate thermal bridging in much thinner tolerances and spaces, it is essential to use a thermally insulating material with lower thermal conductivity values.

Thermablok Aerogel Ltd, our sister company has such materials.

Thermablok Aerogel A2 10mm Insulation Blanket (A2-s1,d0) is a nano particle aerogel which is non combustible with a thermal conductivity of 0.016W/mK, the lowest possible.

It is used in increments of 10mm to insulate many types of issues within construction where space is at a premium and tight tolerances reduce the thickness of material that can be installed.

These include all sorts of applications internally and externally, from steel frames, bifold doors, walls, window reveals, dormers, balconies, roofs and  floors for example.

But back to Open Cell / Mineral Wool – the materials properties, varying densities and increasing thicknesses also enable it to be a sound absorber.

Sound waves are essentially vibrations travelling through the air.

When those waves enter a cavity wall, they pass through the fibres of the mineral wool.

The fibrous structure disrupts the sound energy and absorbs the sound waves, thereby reducing the power, reach and penetration of the sound.

The results will vary depending on depth and density and an increasing noise reduction coefficient (NRC) of the cavity fill used, creating a noticeable drop in noise transmission from one room to another, especially when combined with other specialist soundproofing materials like Acoustiblok Isolation Membrane or Acoustic Sealant.

For more information on Noise Reduction Coefficient (NRC) please see our earlier blog. (add link)

But open cell cavity fill should not only be recognised for the properties of acoustic absorption it offers when installed into a cavity.

Consideration should be given to what would happen if a cavity is left open / empty and the increased resonance that would result.

So worth remembering that the cavity insulation brings a positive value by being installed but also prevents what would be a negative value as well if it were not to be installed.

Types of Mineral Wool Insulation

Mineral wool isn’t a single material, but a category that includes several variants.

Each is suited to different environments and performance requirements:

Alkaline Earth Silicate Wool (AES Wool)

This is a low-bio-persistence mineral wool often used in high-temperature environments, but it also finds application in buildings where minimal irritation and environmental impact are important.

It’s less common in general soundproofing applications.

Alumino Silicate Wool (ASW)

Made from alumina and silica, ASW is highly resistant to heat and is mostly used in industrial furnaces and kilns.

Its acoustic benefits are limited compared to more conventional mineral wools.

Polycrystalline Wool (PCW)

Polycrystalline wool is extremely heat-resistant, often used in aerospace and specialist industrial settings.

It’s not typically found in residential or commercial construction due to cost.

Kaowool

Kaowool is a brand name often used generically for ceramic-based insulation.

It offers some acoustic dampening properties, but like ASW and PCW, its main role is thermal resistance at extreme temperatures rather than soundproofing.

For general building applications, particularly for sound reduction in cavity walls, the more practical and cost-effective solutions are those based on stone wool or slag wool, such as Acoustiblok Quietfibre.

Common Mineral Wool Insulation Brands

Several brands dominate the mineral wool space, each with different strengths.

Here’s how they compare, especially in acoustic applications:

Rockwool

Rockwool is a household name in the insulation world and offers a wide range of stone wool products.

These are often used in general construction for stud walls and flooring systems to improve thermal and acoustic insulation levels.

Acoustiblok

Acoustiblok Quietfibre is a mineral wool specifically designed and well recognised for use in high-performance sound installations such as AV / Cinema for acoustic absorption and reducing of resonance and regeneration of energy.

Quietfibre is made for use within timber or aluminium stud cavity walls as well as flooring systems such as tiered staging, making it ideal for studios, home cinemas, offices, or any environment where sound control is a priority.

It’s designed to work seamlessly alongside Acoustiblok Isolation Membrane, Acoustigrip Jointing Tape, and Acoustic Sealant, to give a complete, integrated soundproofing system.

Acoustiblok QuietFibre is also used as a core which, when wrapped in a wide range of fabric finishes, create frameless AcoustiWall Absorber Panels and AcoustiCloud Ceiling Absorber Panels to absorb echo and resonance thereby vastly improving lively room acoustics.

Knauf

Knauf offers a range of glass and mineral wool insulation products.

While these have the obvious acoustic properties by absorption and reduction of an increase in resonance, they’re generally aimed at thermal insulation first and foremost, with acoustic performance as a secondary benefit.

Superglass

Superglass is another insulation manufacturer with mineral wool products.

Soundproofing Performance of Mineral Wool

When it comes to soundproofing framed cavity walls, mineral wool insulation plays a critical role; but only when used correctly.

The fibres in mineral wool absorb airborne sound waves, significantly reducing echo and transmission between rooms.

However, it’s important to note that absorption is not the same as isolation.

To achieve full-spectrum soundproofing, reducing both airborne and impact noise, mineral wool must be part of a broader system.

For example, in a timber stud wall, Acoustiblok Quietfibre performs best when friction-fitted between the studs, combined with Acoustiblok 3mm Isolation Membrane on one or both wall faces.

Gaps and joints should be sealed with Acoustiblok Acoustic Sealant and Jointing Tape to prevent sound flanking through tiny crevices.

In this setup, Acoustiblok Quietfibre’s high density helps to dampen mid to high-frequency noise, such as speech, music, and TV sound, while the Acoustiblok 3mm Isolation Membrane blocks low-frequency vibrations and structural noise.

Both play a vital role.

Acoustiblok Quietfibre cavity fill offers acoustic absorption between a stud frame as well as reducing resonance and regeneration of the original soundwaves, which occur if allowed to enter an otherwise empty, hollow and cave like cavity.

Acoustiblok Isolation Membrane plays a vital part of thermally converting acoustic energy across the entire wall surface, therefore over the specified mineral wool cavity insulation and critically over the stud framing to reduce the resulting flanking transmission which would occur through a structure’s own rigidity.

This layered approach is far more effective than relying on mineral wool alone in the cavity and hoping for the best by simply boarding over with a finishing board of choice.

A suitable frame for the obvious need for structure and a principle of decoupling.

Full fill / part fill as specified of Acoustiblok Quietfibre for absorption, a noise reduction coefficient and reducing resonance / regeneration.

A complete lining across the entire structure with Acoustiblok Isolation Membrane for thermal conversion of acoustic energy to reduce penetration, vibration and flanking transmissions.

A finishing board of choice which adds mass and density and therefore a principle of deflection.

The result – transforming a standard partition wall which simply divides a space into a barrier that dramatically reduces unwanted noise transmission, all without significantly increasing wall thickness.

Summary

So, what is mineral wool insulation? In short, it’s a dense, fibrous material made from molten rock or industrial slag, designed to trap air and reduce heat and sound transfer.

While it’s long been valued for thermal insulation, its role in soundproofing framed cavity walls is just as important, especially when used as part of a complete system.

Among the options available today, Acoustiblok Quietfibre offers a professional-grade open cell wool solution specifically tailored for acoustic performance.

Designed with sound absorption at its core, it integrates perfectly with other soundproofing components to create quiet, comfortable spaces in both residential and commercial settings.

If you are serious about noise control, especially in partition walls constructed from timber or aluminium studs, Acoustiblok Quietfibre should be your go-to choice.

Not only because it’s effective, but because it is engineered for soundproofing, not just insulation.

Want to know more? Contact our expert soundproofing team for further details.

When you’re dealing with unwanted noise in your home or workplace, understanding the type of noise you’re facing is the first step toward finding the correct solution.

When it comes to soundproofing, not all noise is created equal.

Two of the most common types you’ll encounter are impact noise and airborne noise, but what exactly is the difference between them?

Whether you’re tired of thumping footsteps from the floor above or frustrated by hearing voices coming through the walls, this guide will help you understand what’s causing the disturbance; and more importantly, how to address it effectively.

We’ll break down the science behind these noise types and walk you through proven methods to reduce both, using professional-grade soundproofing materials.

What is Impact Noise?

Impact noise, sometimes referred to as structure-borne sound, is created when an object physically strikes or makes contact with a surface.

That surface, often a floor, wall, or ceiling, vibrates and transmits the sound energy through the building structure.

A common example is the sound of someone walking across a hardwood or tiled floor.

Each footstep generates energy that travels through the floor, down into the ceiling below, and ultimately into your ears.

Unlike airborne noise, which travels through the air, impact noise travels through materials.

Typical examples of impact noise include:

• Footsteps on a floor above
• Furniture being moved or dropped
• Doors slamming
• Objects falling on hard surfaces
• Bouncing balls

Because of its direct contact with the building’s structure, impact noise can be particularly difficult to isolate if not addressed properly.

What Causes Impact Noise?

Impact noise is caused by vibration energy transferring directly from a solid object into a solid surface.

This energy causes the surface to act like a loudspeaker, sending vibrations through the walls, floors, and ceilings of a building.

The degree of impact noise is influenced by:

• The type of flooring (e.g. hardwood floors create more noise than carpets)
• The construction method (e.g. timber joist floors transfer more noise than solid concrete slabs)
• The presence or absence of insulation or underlay

Lightweight, rigid construction materials typically transmit more impact noise than heavier, denser materials.

That’s why you may notice more noise in newer buildings that use lightweight timber frames compared to older properties built from thick masonry.

What is Airborne Noise?

Airborne noise is sound that travels through the air, as the name suggests.

It’s produced when soundwaves from voices, music, televisions, or traffic pass through the air and hit walls, ceilings, windows, and other surfaces which in turn results in Structural airborne noise – a sound that travels through the air and contacts a surface or solid.

If these surfaces aren’t properly insulated or soundproofed, the noise can pass right through.

Common sources of airborne noise include:

• People talking or shouting
• Music or television
• Dogs barking
• Traffic and outdoor noise
• Household appliances

Airborne noise is often the more noticeable of the two types, especially in semi-detached or terraced homes where neighbouring properties share walls.

How Does Sound Travel?

To fully understand the difference between impact and airborne noise, it’s helpful to know how sound travels.

Sound is a vibration that moves through a medium; usually air, but also solids and liquids.

When a sound source produces vibrations:

• Airborne sound travels as pressure waves through the air. These waves hit surfaces and try to pass through them.
• Impact sound travels as vibrations within solid structures, like floors and walls, and radiates as sound when it reaches another surface.

This difference in transmission method is why soundproofing strategies must be tailored to each type.

You can’t block impact noise with exactly the same approach as you would use for airborne noise, and vice versa.

How Impact Noise Differs to Airborne Noise

Here’s a simple way to understand their key differences:

• Impact noise starts with a physical force on a surface.
• Airborne noise starts with soundwaves in the air.

In practice:

• Impact noise is often low-frequency, thudding, and harder to block using traditional insulation.
• Airborne noise is usually higher-frequency, like voices or music, and travels more easily through gaps and lightweight materials.

Another key difference is that impact noise doesn’t need air to travel.

It can move straight through concrete, timber, or steel, whereas airborne noise requires a medium like air to move from one place to another.

Is Flanking Noise Caused by Impact Noise?

Flanking noise is slightly different, but it often includes elements of impact noise.

It refers to sound that travels along indirect paths through a building’s structure, rather than straight through a wall or floor.

For example, sound may bypass a well-insulated wall by travelling along the structure of the said wall or a connected floor or ceiling.

So even if a wall has excellent airborne sound insulation, noise can still “flank” around it.

Impact vibrations can easily become flanking noise, especially in rigid structures without isolation materials.

This is why soundproofing a single element (like a wall) might not be effective if the floor and ceiling connections aren’t also addressed.

How to Soundproof Against Impact Noise

To combat impact noise effectively, you need to reduce vibration transmission at the source.

That means introducing materials that absorb, thermally convert or interrupt the vibration path before it spreads into the structure.

Here’s how you can soundproof for impact noise:

1. Install an Acoustic Underlay

Using a dense acoustic underlay beneath flooring is one of the most effective ways to reduce impact sound from footsteps or dropped objects.

Acoustiblok AcoustiMat Acoustic Underlay is an excellent solution.

It acts as a shock absorber, breaking the direct contact between the floor surface and the structural floor beneath.

2. Add a Specialist Acoustiblok Isolation Layer

Under or within floor build-ups, adding the product Acoustiblok 3mm Isolation Membrane can significantly reduce structure-borne sound transmission.

Despite being just 3mm thick, it converts sound energy through thermal transfer into trace amounts of heat, stopping noise in its tracks.

3. Float the Floor

Creating a “floating floor” by decoupling it from the subfloor can help absorb vibrations.

This typically involves combining underlay, acoustic membranes, and resilient layers.

4. Seal All Gaps

Any gaps or seams can allow both impact and airborne noise to escape.

Use Acoustiblok Acoustic Sealant to create a completely sealed perimeter.

For membrane joins, use Acoustiblok Jointing Tape to ensure full coverage and effectiveness.

How to Soundproof Against Airborne Noise

Airborne noise requires a slightly different approach.

Instead of absorbing vibration, the goal is to block or absorb soundwaves in the air.

1. Increase Levels of Acoustic Isolation of Walls, Ceilings & Floors

Adding specialist acoustic isolation membranes to convert acoustic energy into a less problematic heat energy makes it harder for soundwaves to pass through.

Acoustiblok Isolation Membrane can be fixed within walls, ceilings, or floors to introduce this unique process without taking up significant space or reengineering the entire project.

2. Decouple the Structure

Using acoustic clips or resilient bars, you can separate layers of wall or ceiling.

This breaks the path of vibration and makes it harder for airborne sound to travel.

3. Add Sound Absorption

Within cavities (like stud walls), using an open cell cavity material with a higher density like Acoustiblok QuietFibre can dramatically reduce sound energy within the void. This material also prevents or certainly reduces the effect of resonance and amplification which would certainly happen if the cavity is left as an open (cave like) space.

It works similarly to Rockwool but is purpose-designed for acoustic applications.

4. Add Mass

Incorporate additional layers of higher density finishing board to your wall and ceilings or alternative suitable board for the floors.

5. Seal Gaps and Penetrations

Airborne sound will find its way through the tiniest cracks.

Apply Acoustiblok Acoustic Sealant around electrical boxes, skirting boards, and pipe penetrations to ensure airtightness.

Conclusion

Understanding the difference between impact noise and airborne noise is crucial for identifying the right soundproofing solution.

While airborne noise moves through the air and is easier to block with materials such as Acoustiblok 3mm Isolation Membrane, mass, density and airtight seals, impact noise moves through physical structures and yet again requires Acoustiblok 6mm Isolation Membrane to convert energy to provide vibration isolation to combat.

Both types of noise can be tackled with the right approach, and a mix of the right materials.

Acoustiblok offers high-performance solutions such as the Isolation Membrane, AcoustiMat underlay, QuietFibre insulation, and acoustic sealants and tapes to help you create a quieter, more peaceful environment, whether at home or at work.

If you’re struggling with unwanted noise, identifying the source and applying the right solution can make all the difference.

Get it right, and you’ll enjoy not just a quieter space, but a better quality of life.

Speak to one of our soundproofing experts if your building is experiencing impact noise.

Noise is an inevitable part of modern life, but when it becomes constant, intrusive, or excessive, it starts to pose a serious problem.

This is known as noise pollution, and its impact is often underestimated.

Unlike other forms of pollution, noise leaves no physical trace behind, yet its effects can be just as harmful.

From disturbed sleep to chronic health conditions, the consequences of noise pollution are wide-ranging and affect millions of people every day, particularly in densely populated towns and cities.

In this article, we will explore the causes, mental and physical health implications, and potential solutions to noise pollution, arming you with the knowledge to better understand and reduce its impact in your own life.

What is Noise Pollution?

Noise pollution refers to unwanted or excessive sounds that interfere with normal activities such as sleeping, conversation, or concentration.

It is often described as an invisible threat because, unlike smog or litter, it leaves no visible trace, yet its effects are deeply felt.

In our increasingly industrial and urban environments, noise pollution has become a pervasive issue, affecting both human health and environmental quality.

Behavioural habits of people generally have changed over the years leading to an overall increase of noise from more points of ignition and a lack of thought, understanding, recognition and acceptance of how this can affect fellow humans and the world as a whole.

Whether various types of noise comes from traffic, construction, or even noisy neighbours, persistent exposure to high levels of noise can have serious consequences.

Causes of Noise Pollution

Traffic & Road Noise

Road traffic is one of the most common sources of noise pollution.

In cities and towns, the constant hum of engines, the screech of brakes, honking horns, and tyre noise on poor roads and surfaces all contribute to a relentless din.

As the number of vehicles increases, so does the noise, particularly in areas near major roads and motorways.

Even more rural locations will now have an increased level of noise pollution as population densities and numbers of vehicles increase.

Rail Transport Noise

Trains, particularly high-speed or freight services, generate significant levels of noise.

The impact is greater for those living near busy railway lines or stations.

While trains may pass quickly, the cumulative effect of frequent services can be disruptive, especially during early morning or late-night hours.

Air Traffic Noise

Living near airports or under flight paths exposes residents to aircraft noise, which can be particularly intrusive due to its sudden and high-intensity nature.

The low-frequency roar of jet engines has been linked to a range of health issues, especially when flights operate throughout the night.

Construction Site Noise

Construction work, while temporary, often produces intense noise from machinery, drilling, hammering, and heavy vehicle activity.

Projects in residential areas can lead to constant daytime disruption, affecting sleep patterns for shift workers and concentration levels for those working or studying from home.

Catering & Night Time Economy Noise

Pubs, restaurants, and nightclubs can be significant noise generators, particularly when patrons spill out into the street during late hours.

Music, shouting, and general public disturbance can be a persistent issue for residents living in mixed-use areas.

Animal Noise

While not usually associated with urban noise pollution, animals, especially domestic pets like dogs, can contribute to localised disturbances.

The constant sound of barking from dog cages, for instance, can cause stress for neighbours and contribute to a noisy environment.

Neighbour Noise

From loud music to DIY projects, neighbour noise is a common source of irritation in adjoining buildings, apartment blocks or closely packed neighbourhoods.

It often leads to disputes and can have a particularly personal impact due to its proximity and regularity.

Machinery, Plant & Appliance Noise

Domestic appliances such as washing machines, vacuum cleaners, and lawnmowers, while often overlooked, contribute to indoor and garden noise pollution.

With the increase in Air Handling Units, Heat Pumps and plant generally across many areas of our lives at work or at home there always seems to be a noise issue to contend with.

Industrial machinery in workplace settings also poses a concern, particularly where noise levels exceed safety thresholds.

Mental Health Effects of Noise Pollution

Anxiety & Stress

Continuous or unpredictable noise can activate the body’s stress response, increasing cortisol levels and heart rate.

This persistent state of arousal can lead to heightened feelings of anxiety and unease, especially in people already prone to stress.

Depression

Research has linked long-term exposure to environmental noise with an increased risk of depression.

The constant auditory assault can wear down an individual’s mental resilience, leading to feelings of helplessness and despair.

Fatigue

Even when we are not consciously aware of noise, it can affect our body’s ability to rest and recover.

This low-level interference results in mental and physical fatigue, reducing productivity and lowering overall quality of life.

Disturbed Sleep

Sleep is one of the most commonly affected functions when it comes to noise pollution.

Sounds during the night can delay sleep onset, reduce sleep depth, and cause frequent awakenings.

Sleep is absolutely essential and poor sleep quality is itself a contributor to a range of other health issues.

Behavioural Problems

Children exposed to high levels of environmental noise may exhibit behavioural changes, including irritability, aggression, or withdrawal.

Such disturbances can affect development, school performance, and emotional wellbeing.

Memory & Concentration

Chronic noise exposure can impair cognitive function, making it difficult to focus, retain information, or complete tasks.

This is particularly concerning for students and professionals whose daily responsibilities rely on clear thinking and concentration.

Physical Health Effects of Noise Pollution

Tinnitus & Hearing Loss

Prolonged exposure to high-decibel sounds can damage the sensitive structures in the ear, leading to conditions like tinnitus (ringing in the ears) or permanent hearing loss.

This is particularly common among workers in noisy industrial settings without proper hearing protection.

Headaches

Frequent noise exposure can lead to persistent tension headaches or migraines.

The constant sensory input overwhelms the brain, triggering pain responses and increasing sensitivity to other stimuli.

Cardiovascular Health

Noise pollution is a recognised risk factor for hypertension (high blood pressure) and other heart-related conditions.

The stress induced by noise can affect blood vessels, increasing the risk of heart attacks and strokes over time.

Metabolic Health

Emerging research suggests a connection between noise exposure and metabolic disorders such as obesity and diabetes.

Stress hormones influenced by noise can disrupt metabolism and insulin regulation.

Pulmonary Health

Though less widely known, there is some evidence to suggest that noise pollution may indirectly affect lung function by increasing systemic inflammation and stress, which can worsen conditions like asthma and bronchitis.

Premature Mortality

Taken together, the various health effects of noise pollution contribute to a measurable increase in mortality rates.

Individuals in high-noise environments may experience a reduced life expectancy due to chronic stress and disease burden.

How to Reduce Noise Pollution

Reducing Appliance & Device Noise

Opt for quieter models when purchasing appliances, and keep them well-maintained to minimise operational noise.

Many modern devices include eco or silent modes that can significantly reduce disturbance.

Repair or Replace Old Machinery

Old appliances, boilers, or garden equipment often produce more noise than newer models.

Upgrading or servicing them can improve efficiency and cut down on disruptive noise.

Soundproof Your Home

Installing acoustic insulation in walls, ceilings, and floors can dramatically reduce the amount of external and internal noise that enters or escapes a building.

High quality double glazing in conjunction with professional grade soundproofing materials such as Acoustiblok 3mm Sound Insulation Membrane on walls, as well as Acoustiblok Quietfibre Open Cell MIneral Wool Insulation in wall cavities will have a dramatic effect on reducing unwanted noise ingress.

Acoustically Treat and Soundproof Your Garden

Soundproof your garden by erecting acoustic fencing, planting dense hedges, or creating sound-dampening landscaping features.

This can reduce noise from nearby roads or neighbours, making outdoor spaces more peaceful.

Adding high grade Acoustiblok Noise Barrier Fencing Membrane appropriately will have a massive impact on reducing noise from entering your garden from external sources.

Ear Protection

In particularly noisy environments, whether at work, during DIY projects, or even in certain urban settings; wearing earplugs or noise-cancelling headphones can protect your hearing and reduce stress.

Organise More Quiet Time

Scheduling time each day to be free from digital devices, loud music, and other distractions can help reset the nervous system.

Activities such as reading, meditation, or walking in nature are excellent ways to embrace calm.

Conclusion

While it may seem intangible, the consequences of noise pollution are very real.

From disrupted sleep and impaired mental health to long-term physical conditions, chronic exposure to noise affects every facet of human life.

Understanding the sources and impacts of noise is the first step towards mitigating it.

Whether through lifestyle changes, soundproofing solutions, or advocating for quieter communities, taking action on noise pollution is not just about comfort, it’s about protecting our health and wellbeing for the long term.

Imagine sitting in a busy open-plan office, a concert hall, or even a modern home theatre where sound clarity is paramount.

The design of these spaces is often underpinned by one critical measurement: the Noise Reduction Coefficient (NRC).

In simple terms, the NRC quantifies how effectively a material can absorb sound.

This article aims to provide a comprehensive overview of the Noise Reduction Coefficient – what it is, how it is measured, its history, the factors affecting it, and how it compares to other acoustical metrics.

Whether you’re an architect, interior designer, a design professional, contractor or simply curious about how your favourite spaces manage sound, this guide is for you.

What is Noise Reduction Coefficient?

The Noise Reduction Coefficient, commonly abbreviated as NRC, is a single-number rating that indicates the average sound absorption performance of a material.

Typically expressed on a scale from 0 to 1, the NRC value represents the proportion of sound energy that a surface absorbs rather than reflects.

An NRC of 0 means the material reflects all sound, while a value of 1 means it absorbs nearly all the sound that strikes it.

The NRC is calculated by averaging the sound absorption coefficients of a material at four key frequencies:

• 250 Hz
• 500 Hz
• 1000 Hz
• 2000 Hz.

These frequencies are chosen because they fall within the range most critical for human speech and everyday noise.

In essence, the NRC offers a simplified way for architects, acousticians, and engineers to compare the performance of different types of soundproofing materials in terms of their sound absorption capabilities.

What is the NRC Scale?

The term “NCR scale” refers to the measurement scale used to denote the Noise Reduction Coefficient.

This scale typically ranges from 0.0 to 1.0:

• 0.0 – Indicates no sound absorption; the material reflects all sound.
• 1.0 – Denotes near-total sound absorption; the material captures almost all incident sound energy.

While the NRC value gives a useful snapshot of a material’s acoustic performance, it’s important to understand that it is an average measure.

It doesn’t account for the nuances of sound behaviour at frequencies outside the selected range, nor does it detail how a material might perform in real-world conditions where installation methods and environmental factors come into play.

History of Noise Reduction Coefficient (NRC)

The development of the Noise Reduction Coefficient rating has its roots in the mid-20th century when the science of acoustics was becoming increasingly important for architectural design and public health.

Early acoustic research focused on understanding how different materials interacted with sound waves.

As the need for improved sound management in public spaces and industrial environments grew, standardised methods for measuring sound absorption were developed.

Originally, acoustic measurements were complex and required elaborate testing in specially designed reverberation rooms.

Over time, as testing methodologies evolved and became more accessible, the NRC emerged as a practical and simplified metric.

It allowed designers and engineers to compare materials quickly without delving into the intricate details of acoustic frequency response curves.

Today, the NRC is widely recognised in building codes and industry standards.

Its simplicity has made it a favoured tool for those looking to enhance acoustic performance in a variety of settings, from educational establishments and offices, to theatres and recording studios.

How is Noise Reduction Coefficient (NRC) Calculated?

Calculating the Noise Reduction Coefficient involves measuring a material’s sound absorption coefficients at specific frequencies.

Here’s a step-by-step outline of the process:

1. Laboratory Testing: The material sample is placed in a reverberation room or an impedance tube – a controlled environment where sound can be precisely measured.
2. Frequency Measurements: Sound is directed at the material, and its absorption is measured at four standard frequencies: 250 Hz, 500 Hz, 1000 Hz, and 2000 Hz. As previously referenced, these frequencies are critical as they represent the range most important for human hearing.
3. Averaging the Results: The individual absorption coefficients at these frequencies are averaged to give a single NRC value. For example, if a material has absorption coefficients of 0.70, 0.75, 0.80, and 0.85 at the four frequencies, its NRC would be the average of these values.

It is worth noting that while the NRC provides a convenient and widely accepted metric, it does have limitations.

It does not reflect how the material performs at frequencies below 250 Hz or above 2000 Hz, nor does it consider the directional properties of sound in a real-world setting.

Nevertheless, for most practical purposes, the NRC offers a reliable guide for material selection in acoustic design.

Factors that Affect Noise Reduction Coefficient (NRC)

Several factors can influence the measured NRC of a material.

Understanding these factors is essential for both accurate testing and optimal material selection in practical applications.

Mounting & Installation

How a material is mounted or installed can have a significant impact on its sound absorption properties.

Materials are often tested in ideal, laboratory conditions where they are flat and unimpeded.

However, in real-world applications, the mounting technique can alter a material’s performance. For example:

• Flush Mounting: When a material is applied directly against a wall or ceiling, there is little to no air gap, which might limit low-frequency absorption.
• Suspended or Air-Gap Mounting: Introducing a small gap between the material and the supporting surface can enhance absorption, particularly at lower frequencies, by allowing the material to vibrate and dissipate sound energy more effectively. This can also increase the levels of absorbency achieved as the surface area of the rear of each panel is brought into play (rear effect).

Sample Size

The size of the sample used in testing can also affect the measured NRC.

Standardised tests typically use samples of a specific size to ensure consistency and comparability.

However, in practice, the acoustic performance of a material can vary with the size of the installation.

Smaller samples might exhibit edge effects that can either boost or diminish the overall absorption, while larger installations might behave differently due to the cumulative impact of these effects.

Thickness

Thickness is one of the most critical factors influencing a material’s NRC rating.

In general, thicker materials tend to absorb more sound, especially at lower frequencies.

This is because a greater thickness allows for a longer path through which sound energy can be dissipated.

Conversely, thinner materials might be effective at higher frequencies but perform less well at absorbing bass or lower frequency sounds.

Designers must consider the trade-off between thickness, weight, and installation requirements when selecting materials for acoustic applications.

Acoustiblok Absorber Panels for wall mounting or Acoustiblok AcoustiCloud Panels for ceiling mounting are available in all shapes and sizes but typically available in two differing thicknesses of either 25mm or 40mm.

What’s Considered a Good NRC Rating?

In the context of the NRC scale, a higher value indicates better sound absorption.

Materials with NRC ratings above 0.70 are generally considered effective for most acoustic applications. For instance:

• Moderate Performance: An NRC of around 0.5 to 0.6 might be acceptable in environments where complete sound control is not critical, such as in some commercial or residential spaces.
• High Performance: An NRC rating of 0.8 or higher is typically sought after for spaces that demand high levels of sound absorption, such as recording studios, theatres, and conference rooms.

Acoustiblok QuietFibre for example, displays the highest levels of NRC ratings which means there are no or minimal reflections.

It is important to remember that what constitutes a “good” NRC rating can vary depending on the specific acoustic needs of a space.

A material with an NRC of 0.7 might be perfect for one application, while another scenario might demand a material with an NRC closer to 0.9.

Is a High NRC Rating Better?

At first glance, a higher NRC might seem inherently better, but the answer isn’t always straightforward.

While a high NRC indicates superior sound absorption, several other factors must be taken into account:

• Design Requirements: In some spaces, complete absorption might not be the desired outcome. For example, certain rooms may require a balance between absorption and reflection to maintain a lively acoustic environment.
• Cost and Practicality: Materials with very high NRC ratings may be more expensive. The cost-benefit ratio should be carefully evaluated taking into account absorbency / effect over the available tolerances / depths of solutions that can be tolerated.
• Additional Properties: Acoustic performance is just one aspect of a material’s suitability. Factors such as fire resistance, durability, aesthetics, and ease of maintenance also play a crucial role in material selection.

In summary, while a high NRC rating is generally desirable for maximizing sound absorption, it is not the only consideration when designing an acoustically treated space.

Typical Applications

The Noise Reduction Coefficient is an essential metric in a wide range of applications.

Here are some common scenarios where NRC is particularly important:

• Recording Studios and Theatres: High NRC-rated materials are used to control reverberations in studio soundproofing to ensure clear, high-quality sound.
• Offices and Conference Rooms: In open-plan offices and meeting rooms, materials with appropriate NRC ratings help reduce background noise and improve speech intelligibility.
• Educational Institutions: Classrooms and lecture halls benefit from acoustic treatments that prevent sound from becoming overwhelming, thus enhancing learning.
• Restaurants and Public Spaces: Ensuring a comfortable acoustic environment in busy restaurants or public areas can improve the overall experience for visitors.
• Industrial and Commercial Environments: In spaces where noise control is critical for safety and productivity, materials with effective NRC ratings are essential for industrial soundproofing.

By selecting materials with the appropriate NRC rating for each application, designers and engineers can create environments that are both functional and acoustically pleasing.

NRC vs SAA: What’s the Difference?

At times, you may encounter the term Sound Absorption Average (SAA) alongside NRC.

While both metrics aim to provide a single-number representation of a material’s sound absorption capabilities, there are subtle differences between them.

Measurement Methodology

The SAA is often derived from a broader range of frequency measurements or alternative averaging methods.

While NRC is based on four standard frequencies, SAA might include additional frequency bands, offering a slightly different perspective on a material’s performance.

Application Context

Different regions or industries may prefer one metric over the other based on historical practices or specific regulatory requirements.

Despite these differences, both NRC and SAA serve as useful guides for comparing acoustic materials.

NRC vs STC: What’s the Difference?

It’s important not to confuse NRC with Sound Transmission Class (STC), as they measure entirely different aspects of acoustical performance:

Noise Reduction Coefficient (NRC) focuses on how much sound a material absorbs within a space.

It provides a single-number rating that reflects the material’s ability to reduce sound reflections and reverberations.

Sound Transmission Class (STC) on the other hand, measures how well a building partition, wall, or barrier blocks the transmission of sound from one room to another.

This is where the super thin, advanced and unique Acoustiblok 3mm Isolation Membrane or Acoustiblok 6mm Isolation Membrane materials would be the choice to easily incorporate into a stud wall, ceiling or floor for example to mitigate sound leakage or ingress whilst saving space and without the need to redesign the entire buildup /project.

STC values are particularly relevant in evaluating the effectiveness of walls, floors, and ceilings in preventing sound leakage.

Acoustiblok Isolation Membranes have staggering STC level.

• 3mm – Average STC 26
• 6mm – Average STC 32

While both NRC and STC are vital for acoustic design, they serve different purposes.

An ideal acoustic design might require a careful balance between materials with high NRC ratings to manage internal sound quality and high STC ratings to control sound transmission between spaces.

Conclusion

The Noise Reduction Coefficient (NRC) is a fundamental metric in the field of acoustics, serving as a key indicator of a material’s sound absorption capabilities.

From its straightforward 0 to 1 scale to its critical role in shaping environments – from recording studios to modern open-plan offices – the NRC helps designers and engineers create spaces that are both comfortable and functional.

Understanding the factors that influence the NRC, such as mounting type, sample size, and thickness, is essential for making informed choices about acoustic treatments.

Moreover, recognising the differences between NRC, SAA, and STC ensures that the right material is chosen for the specific acoustic needs of any project.

By grasping these concepts, you can better appreciate how sound is managed in the built environment and make smarter decisions when it comes to designing spaces that cater to both form and function.

Whether you are a seasoned professional or a curious newcomer to the field of acoustics, the Noise Reduction Coefficient offers a window into the science of sound absorption – one that can make a significant difference in how we experience our everyday environments.

For further guidance and advice about NCR, contact a reputable soundproofing professional for help.

Sound attenuation is a critical concept in noise control and acoustics.

It refers to the reduction of sound intensity as it travels through a space.

Whether in industrial and commercial settings, vehicle engineering, or residential environments, understanding sound attenuation helps in designing spaces that require controlled sound levels.

In the chapters below we provide an overview of what sound attenuation is, its significance, the methods to achieve it, and how it is calculated.

What is Sound Attenuation?

Sound attenuation describes the gradual decrease in sound intensity as it propagates from a source.

This reduction occurs due to several factors, including distance from the sound source, absorption by materials, and interference with physical barriers.

Attenuation is typically measured in decibels (dB) and quantifies how much sound energy is diminished along its path.

What is the Purpose of Sound Attenuation?

The primary purpose of sound attenuation is to manage noise levels to create environments conducive to safety, comfort, and compliance with noise regulations.

Sound attenuation can enhance productivity, protect hearing, and ensure environments meet required regulatory standards.

Why is Sound Attenuation Important?

Sound attenuation has broad applications across various industries, with each sector experiencing unique challenges and solutions:

Automotive

In the automotive industry, sound attenuation improves passenger comfort by reducing engine, road, and aerodynamic noise within the cabin.

Specialist acoustic materials and barriers are used to ensure that vehicles meet noise standards while delivering a pleasant experience for passengers.

Aerospace

For aerospace, sound attenuation is crucial for passenger safety and comfort, given the intense engine noise and aerodynamic sounds.

Engineers rely on advanced materials and designs to minimise noise both inside aircraft cabins and in the surrounding environment.

Entertainment

In entertainment, sound attenuation allows for controlled audio experiences, whether in movie theatres, concert venues, or recording and film studios.

Soundproofing walls and specialist soundproofing materials help maintain sound quality while preventing noise spillover.

Commercial

Sound attenuation is also an important consideration within commercial spaces.

Whether the space is an office or boardroom, hotel, restaurant or a manufacturing facility where noise and sound creation levels are key considerations for the health and welfare of its employees.

Residential

It is well documented that noisy living can impact health, therefore sound attenuation is an especially important factor within residential dwellings.

Sound travelling through party walls or impact noise through ceilings and floors in flats, apartments and multi occupancy (HMO) dwellings are key areas for consideration.

How to Achieve Sound Attenuation

Sound attenuation can be accomplished using various techniques, primarily involving soundproofing and sound absorption principles.

Soundproofing

Soundproofing is designed to block sound from passing through barriers.

By creating obstructions to airborne sound waves, soundproofing materials like Acoustiblok 3mm sound isolation membrane, specialised drywall, or heavy doors, prevent noise from entering or leaving a space.

Acoustic membranes are commonly used in settings requiring privacy or sound isolation, such as residential, offices, schools, studios, cinemas and an array of vehicles and marine craft.

Soundproofing focuses on structural barriers and is essential in limiting sound transmission.

Sound Absorption

Sound absorption, on the other hand, deals with controlling sound within a space by reducing echo and reverberation.

Materials used for absorption, such as dense open cell mineral membranes, Acoustiblok Acoustic Wall Panels and foam, are engineered to trap and dissipate sound waves, converting them into trace heat energy.

Unlike soundproofing, which blocks noise, absorption techniques improve audio clarity in spaces like theaters, recording studios, and open offices.

Both soundproofing and absorption are fundamental to effective sound attenuation, with each method offering unique benefits depending on the environment and noise-control requirements.

How to Calculate Sound Attenuation

Calculating sound attenuation helps determine how much sound intensity reduces over a distance or through a medium.

The inverse square law is a common principle for calculating sound attenuation, especially in open environments.

According to this law, the sound intensity decreases proportionally to the square of the distance from the source.

Therefore, doubling the distance from the source results in a quarter of the sound intensity.

For controlled spaces with sound barriers, attenuation coefficients are used to predict how much sound is absorbed or reflected by materials.

Materials are rated for their Sound Transmission Class (STC) or Noise Reduction Coefficient (NRC), indicating their effectiveness in sound reduction and absorption, respectively.

This data can be used alongside attenuation formulas to determine precise sound levels and plan effective noise-control strategies.

Pros and Cons of Sound Attenuation

Implementing sound attenuation strategies has numerous benefits but also some limitations.

Pros

• Improved Comfort and Productivity: In workspaces, sound attenuation reduces distractions, enhancing concentration and productivity.
• Health and Safety: Attenuation minimises exposure to potentially damaging noise levels, protecting hearing health.
• Enhanced Audio Quality: In theatres and studios, sound attenuation improves sound clarity and reduces disruptive echoes.

Cons

• Cost: High-quality materials and structural modifications for soundproofing and absorption must be budgeted for.
• Space Constraints: Installing soundproofing solutions may require additional space, some considerably more than others which can be challenging in small areas.
• Complexity: Achieving the ideal balance between soundproofing and absorption requires planning, especially in spaces with varying noise levels.

Conclusion

Sound attenuation is essential for controlling noise across industries, from transportation to entertainment and residential spaces.

Understanding and implementing effective attenuation strategies can significantly improve environments for comfort, productivity, and health.

Through soundproofing, absorption, and accurate calculations, soundproofing professionals can ensure spaces meet noise-reduction standards tailored to specific needs.

Whether in open environments or confined spaces, sound attenuation remains a vital aspect of modern acoustics and engineering.

In a world filled with noise, finding peace and quiet can be a challenge.

Whether it’s the sound of traffic outside your window, neighbours in a bustling apartment building, or the constant hum of activity in the office, unwanted noise can be more than just a distraction – it can affect your mood, productivity, and even your health.

This is where sound isolation material comes in.

By creating barriers that prevent noise from traveling between spaces, sound isolation offers a practical solution to maintaining quiet and privacy in any environment.

In this article, we’ll explore what sound isolation is, how it works, and why it’s essential in both residential and commercial settings.

Whether you’re a homeowner looking to create a peaceful sanctuary or a professional aiming to isolate or improve acoustics, understanding sound isolation can help you achieve your goals.

What is Sound Isolation?

Sound isolation refers to the process of preventing sound from traveling from one space to another.

Unlike sound absorption, which deals with reducing reverberation, resonance, echo and noise within a room, sound isolation aims to prevent sound transmission entirely.

Be that ingress or leakage.

This is typically achieved by employing standard principles and specialised construction techniques to create partitions that stop sound waves from passing through walls, floors, ceilings, and doors.

Sound Isolation vs Sound Absorbtion

Though they are often confused, sound isolation and sound absorption serve different purposes in controlling acoustic energy.

Sound isolation is all about preventing sound from escaping (leaving) or ingress (entering) a space.

This is crucial when dealing with so many different types of noise in everyday life.

Examples may include noisy neighbours, home studios, room to room in dwellings, offices, board rooms, treatment rooms, recording studios – or any situation where external noise ingress or internal sound leaking is a concern.

The goal is to create a partition or barrier that prevents movement from A to B or B to A depending on your situation.

But what do you build that partition or barrier with?

Our previous articles highlight the key principles that may be considered depending on the construction method.

Varying approaches are adopted which may include:

• density and mass (deflection)
• framing systems (decoupling)
• open cell material (absorption)
• acoustic isolation materials (thermal conversion)

By contrast, acoustic calibration or balancing of internal acoustics by way of surface sound absorption, focuses on improving the acoustics within a space to ensure accuracy of acoustic performance, reflection and resonance.

This principle works by absorbing excess sound energy inside a room, reducing echo and reverberation. 

Absorptive materials within a space help control noise levels, making a room sound clearer and less noisy.

These spaces may already include carpets, sofas, curtains and cushions and where further specific solutions are required Acoustic Wall Absorber Panels, or Acoustic Ceiling Absorber Panels, foam panels, baffles, diffusers.

But to be clear – these methods do not prevent sound from escaping or entering.

Sound Isolation vs Sound Cancellation

It’s also important not to confuse sound isolation with sound cancellation.

While sound isolation prevents soundwaves by whatever means from traveling between spaces, sound cancellation involves actively counteracting sound waves.

This is most commonly used in noise-canceling headphones, which emit a sound wave that cancels out external noise.

Sound cancellation is an active technology, requiring electrical components, while sound isolation is passive, relying on structural changes and materials.

Benefits of Sound Isolation

The benefits of sound isolation are numerous, especially in environments where controlling noise is crucial.

Some key advantages include:

Improved Privacy

Whether in a home or office, sound isolation ensures conversations and activities remain private by preventing sound leakage.

Noise Reduction

In urban environments, isolating sound can significantly reduce the intrusion of outside noise, making homes quieter and more comfortable.

Enhanced Productivity

By blocking distracting sounds, isolated spaces like home offices or studios allow for better concentration and focus.

Better Sound Quality

For musicians or anyone creating audio content, sound isolation helps ensure external noises don’t interfere with recordings, delivering clearer, more professional results.

How Sound Isolation Works in Walls

Walls are one of the primary barriers for sound isolation, but standard drywall often fails to block sound effectively.

Decoupling

To isolate sound in walls, the most common approach is to construct a thin framed partition from timber or steel stud of varying thicknesses to best fit the specific requirements of depth, tolerance and acoustic performance. 

Framing or decoupling separates the surfaces on either side of a wall so sound waves cannot travel directly through them.

This is often achieved with a single stud or in some scenarios double-stud walls, sometimes with or without resilient channels which offer an additional principle of decoupling.

Open Cell Cavity Insulation

Filling the studded wall cavity with sound-dampening insulation like Acoustiblok QuietFibre can reduce sound transmission by absorbing sound energy within the open space.

This principle is essential to not only absorb but crucially to also prevent resonance and regeneration of acoustic energy that would otherwise likely occur in open cavities.

Thermal Conversion of Acoustic Energy

Applying Acoustiblok 3mm isolation membrane onto the framing system will greatly improve acoustic isolation and reduce flanking transmissions.

Acoustiblok Isolation Membrane is unique in application, is flexible and versatile and will increase acoustic performance whilst reducing the depth of the build by outperforming other materials millimetre for millimetre.

This thin material offers so much effect by thermally converting the acoustic energy via vibrations, thereby transfering a more problematic acoustic energy into a far less troublesome trace heat energy. 

It gives significant improvements in acoustic isolation within minimum wall depths to retain precious space and gross internal areas.

Adding Mass & Density

The denser the material, the better it will block sound.

Adding extra layers of drywall or plasterboard can assist as further mass and density is achieved.

However, it can rarely achieve the acoustic values to isolate, as the material’s own rigidity can result in flanking transmissions still being evident.

Materials like Acoustiblok Acoustical Sound Sealant can be applied between layers of finishing board to further absorb sound vibrations from one to another.

How Sound Isolation Works in Floors

Floor sound isolation is especially important in buildings with multiple floor levels.

Sound can travel not only through airborne noise but also via impact noise, such as footsteps. 

To effectively isolate sound in floors, a combination of materials and techniques is typically used. 

Which strategy to employ is usually determined by a number of factors. 

These can include:

• the type of existing structure and the performance it provides
• the structure helps or hinders the movement of sound
• if the dwelling is for residential, commercial or industrial use
• the choice and type of  floor desired
• the type and levels of noise to be isolated
• the desired acoustic levels to be achieved
• the overall assembly depth of the proposed buildup to available tolerances

Depths of solutions can range greatly.

The simple rule of thumb is, try using thicker solutions to evaluate what works and what doesn’t..

Where the thinnest assemblies are required whilst achieving increased and meaningful acoustic levels, more advanced solutions need to specified such as Acoustiblok 6mm Isolation Membrane or Acoustiblok 3mm Isolation Membrane.

These may be installed in tandem with varying materials and types of sub floor and Acoustic Underlays followed by the choice of finishing floor.

Open Cell Cavity Insulation

With a framed floor of joists such as timber, the cavities can be filled or part filled with acoustic quilt or open cell wool slabs.

Filling the floor cavity with sound-dampening insulation like Acoustiblok QuietFibre can reduce sound transmission by absorbing sound energy within the open space.

This principle is essential not only for absorbing acoustic energy but also for preventing resonance and the regeneration of sound, which would otherwise occur in open cavities.

Dense Materials

Applying additional layers of increased dense materials like plywood or OSB board can add mass to the assembly and may improve results.

This is typically required at some point in most assemblies in way of a subfloor, but experience tells us that this alone can still result in flanking transmissions and a knock-on effect via the materials’ own rigidity.

Floating Floors

A floating floor system involves laying flooring on top of a rubber or foam underlay, decoupling it from the subfloor and reducing the amount of impact noise that travels between rooms.

Acoustic Cradles

Where a much increased depth of solution can be tolerated and a higher acoustic level is required, specialist Acoustic Cradles can be installed onto a concrete slab for example. 

These ‘cradles’ or ‘towers’ are made from recycled rubber crumb materials and are arranged in a specific pattern on the floor to support a suspended timber batten system, minimising direct contact.

This framing system decouples the floating floor from the structural floor, though it does significantly increase the overall finished height.

Carpeting and Rugs to Floor Surfaces

Adding soft, thick materials to the surface of the floor, such as carpets and rugs, can help absorb some of the impact noise.

But it is unlikely to achieve an acoustic level, rather just prevent direct impact of footfall for example.

How Sound Isolation Works in Ceilings

Ceilings are another common source of sound transmission, especially in multi-storey buildings.

Just like with flooring, it’s important to assess the type of in-situ assembly, such as solid concrete, block and beam, or timber joists, and select materials that align with the appropriate design strategies.

Open Cell Cavity Insulation

With a framed floor of joists such as timber, the cavities can be filled or part filled with acoustic quilt or open cell wool slabs.

Filling the wall cavity with sound-dampening insulation like Acoustiblok QuietFibre can reduce sound transmission by absorbing sound energy within the open space.

This principle is essential to not only absorb, but crucially, to also prevent resonance and regeneration of acoustic energy that would otherwise likely occur in open cavities.

Isolating sound with solid types of construction may involve techniques like suspended or drop ceilings which hang from the structure above. 

Isolation Clips and Hangers

These decouple the ceiling from the joists above, reducing the amount of vibration that can pass through.

Unique Material for Thermal Conversion of Acoustic Energy

Similar to walls and as referenced above, adding more advanced solutions namely Acoustiblok 3mm Isolation Membrane into the ceiling buildup will greatly increase the levels of acoustic attenuation via thermal conversion.

Dense Materials

Applying additional layers of dense materials like acoustic plasterboard or even plywood can add mass, but always evaluate the additional weight that the structure can support.

Adhesives & Silicone Compounds

Using adhesives and silicone compounds between extra layers of plasterboard or drywall helps minimise the transmission of natural resonant frequencies from one solid surface to another.

How Sound Isolation Works in Doors

Doors are one of the weakest points to achieving sound isolation because they often have gaps and are made of lightweight materials.

To enhance sound isolation in doors, several strategies can be employed:

Solid-Core Doors

Replacing hollow-core doors with solid-core doors increases mass, making it harder for sound to pass through.

Sealing Gaps

The gaps around doors can allow sound to leak through.

Installing door sweeps, weatherstripping, and acoustic seals can block these gaps effectively.

Door Stops

Increasing the size and width of the beading on the door frame can increase the surface area of contact when the door is closed onto the door stop.

This can have a great effect in closing down the gaps that would otherwise be present and allow acoustic energy to leak through.

Acoustic Panels

In some cases, attaching soundproofing panels directly to the door can further reduce sound transmission by softening the surface and absorbing energy. 

Conclusion

Sound isolation is a vital process for anyone looking to block unwanted noise from entering or leaving a space.

Whether you’re creating a quiet home, soundproofing a music studio, or simply looking to improve privacy, sound isolation can make a significant difference.

By employing techniques such as adding mass, decoupling surfaces, applying advanced Acoustiblok 3mm Isolation Membrane, adding absorbing materials and sealing gaps, you can effectively block sound transmission through walls, floors, ceilings, and doors.

When combined with other noise control measures, sound isolation can help create a more comfortable, peaceful, and productive environment.

If you’re unsure about how to start a sound isolation project, then speak to a soundproofing expert for help and advice.

In essence, sound isolation is about preventing sound from travelling between spaces using physical barriers, and it’s distinct from sound absorption and sound cancellation.

It provides numerous benefits, from improving privacy to enhancing the quality of recorded audio, making it an essential aspect of modern noise control.

Soundproofing is a specialism that revolves around effectively controlling unwanted noise, with various soundproofing materials used to mitigate the effects of noise. Anything from people who want a quieter home and tranquility from noisy next door neighbours, to businesses who need to reduce the noise impact that they make on surrounding areas, soundproofing comes with a long list of causes and solutions. In fact, there are a myriad of soundproofing materials that one can choose from to apply to different uses. Some are more suitable or effective than others, which greatly depends on the type of noise created, the source of the noise, the structure of the building, wall construction, and various other key factors. To understand soundproofing materials and how they perform, it is important to mention that sound is a form of energy. Sound travels from a source, and during the distance that it travels it causes vibrations whenever it hits air and any objects in its path. These sound waves then reach the recipient’s ears and stimulate the brain. Soundproofing materials work to reduce the sound pressure created from the source to the receptor. In this in-depth article, we’ll explore the 30 best known soundproofing materials in more detail, how they perform and where they are best used.

Soundproofing vs Sound Absorption

Before exploring soundproofing materials, it is advised to firstly understand the key differences between sound absorption and soundproofing. It’s a common misconception to think that sound absorption is the same as soundproofing. In reality they are not one and the same. Sound absorption is in actual fact one element of sound proofing and is used in two ways: Firstly, as part of a soundproofing system, as a material which is invariably added within a structure such as between the voids created in a stud wall, which can reverberate sound, adding sound absorption can prevent this. Secondly, when sound absorbing materials are added to the surface of a wall or ceiling, it absorbs sound waves and reduces resonance and regeneration of the sound back into the room. In doing so, improves the acoustics of a room which is called acoustic calibration. For example, a noisy restaurant with hard surfaces typical of industrial influenced design of today’s trendy eateries, can result in a cacophony of sound from clattering cutlery and chattering diners. This noise can be softened with panels of sound absorbing materials which equalize and balance the internal acoustics of a room which is acoustic calibration. Hopefully this explanation is reasonably clear, but in a nutshell, sound ‘absorbing’ materials reduce the resonance and reverberation of sound waves within a space or room. Sound ‘proofing’ materials prevent sound waves from passing in or out of the room.

Key Principles of Soundproofing

Soundproofing is acoustic isolation – the prevention of sound waves passing in or out of a room. In order to understand soundproofing or acoustic isolation, it is best to start by highlighting the key principles, namely:

Deflection

Deflection of sound is achieved by adding mass and density to any structure such as a wall, floor or ceiling. All solid materials which have a thick consistency and are dense or somewhat heavy, can help to block sound. By adding mass and dense materials between the source of the sound and the receiving point will offer additional bulk that the sound wave will have to pass through and in doing so will reduce its energy. Increased mass and density of a wall ‘s construction can be achieved with concrete for example, or dense finishing boards such as ply, OSB, drywall or plasterboard. Deflection with mass and density proves more effective with airborne sounds such as voices or music, and not so effective with impact noise such as foot fall, which is usually associated with stronger power, pressure and therefore vibration. As sound waves strike the mass and dense materials, vibration will occur and in doing so will pass the energy from one side to the other through the materials’ own rigidity. This is the principle of flanking transmission noise – a common problem with all structural scenarios.

Absorption

Open cell woven types of material such as QuietFibre Stone Wool Cavity Insulation, which provides a soaking up or absorption of the acoustic energy entering it. These are available in differing thicknesses and densities for an increasing effect and are usually installed in open cavities where the depth of material can be tolerated. Not only do these types of absorptive materials offer absorption, but it is also important to know that by filling a cavity they can also prevent the potential of additional resonance, reverberation or amplification of sound waves that could be created if the cavity were to be left completely empty.

Decoupling

The principle of decoupling is to reduce the area of direct mechanical linkage between the substrate or structure, say for example of a wall, and the finishing materials. This process is a way of interrupting sound vibrations or flanking transmissions that travel through the structures’ own connectivity or rigidity from one side to the other. This may well be by a complete decoupling of an internal structure such as what is commonly called a ‘room within a room’ or a ‘cell within a cell’ or may simply be a decoupling by counter battening or resilient channels. A good example is the use of acoustic brackets, acoustic hangers or resilient channels, which will help to decouple drywall from the rest of the building’s structure. As a result, the strength of the acoustic vibrations are reduced, thus slowing their potential passage through the wall. Decoupling is best done during the construction phase of a building.

Thermal Conversion

Acoustiblok Isolation Membrane is a material which works by converting sound energy into trace heat energy. When sound waves come into contact with the membrane, it vibrates the molecules of the materials which in turn creates friction which is cleverly converted to a trace heat energy. Thus the material works by converting a more problematic acoustic energy into a less problematic heat energy which is simply transferred through the material sideways to reduce flanking transmissions. In any serious or advanced strategy to isolate sound, this is an absolute must to work in tandem with the other principles. At only 3mm thick, the depth of the material is hardly noticeable in the grand scheme of things, but the benefits to uplift acoustic performance are immense. The material has an optimum balance of mass and flexibility, however it does not rely only on its mass for acoustic performance, making it a unique and standalone sound proofing material.

Constrained Layer Damping

Constrained layer damping is a principle of using specific materials in particular ratios to reduce the natural resonant frequencies of the structure, thus reducing the resulting flanking transmissions through from one side of the structure to the other. Damping compounds are effective when applied between two rigid panels, such as drywall or plasterboard for example. As a result, when the sound hits it, shearing forces between the panels creates friction in the damping layer and the sound ceases as it is converted to heat, in essence thermal conversion occurs. This solution is ideal for low-frequency noises.

Key Takeaway

These essential principles of soundproofing outlined above work independently of each other, but can also complement one another. Often, combining different methods by using two, three, four or more of these principles offers the best results.

Types of Soundproofing Materials

There’s an extensive list of soundproofing materials that you can choose from, for various applications. Each of these materials has different best use scenarios, and they work by means of one or more of the soundproofing principles outlined above. Let’s go over them in more detail to highlight key aspects of the material and how and when they are best used:

Acoustic Isolation Membrane

There are quite a few ‘acoustic membranes’ on the marketplace, with some being better than others. The most advanced membrane in this category is the unique Acoustiblok Isolation Membrane which is the thinnest and highest performing material available, mm for mm. It is considerably lighter and enables a higher thermal conversion of energy from an acoustic energy into a less problematic heat energy and transfer through itself. This material which is available in 3mm and 6mm thicknesses, is commonly installed within walls, ceilings and floors to mitigate airborne and impact sound. Remarkably, it helps to block sound transfer more effectively than a sheet of lead and is ideal for sound insulation. It is polymer-based and thus very flexible, adaptable and easy to install. It offers effective acoustic insulation without increasing the thickness of walls or ceiling, or loading with excessive weight for example. Some other materials are known as Mass Loaded Vinyl (MLV) which are simply a rubber compound impregnated to increase mass and density. These are much heavier materials and rely heavily on a deflective principle.

Open Cell Cavity Insulation

This material is typically installed into cavities, and tends to be made from rock wool,stone wool, mineral wool or fibreglass. QuietFibre is an example of a stone wool. They are designed to fit snugly between wall studs, ceilings and floors and uses the principle of sound absorption. By doing so they will effectively pack out the airspace usually found in these areas, and so the transmission of sounds are impeded or considerably reduced by their presence.

Decoupling Products

Based on the principle of decoupling materials through which sound is transmitted.

• Resilient Channels – there are varying types from simple timber battens to aluminium metal rails that are specially designed to lay over soundproofing insulation once they are mounted across wall studs or ceiling joists.
• Acoustic Hangers – which are isolation mounts which mechanically fix to the main structure and act as a gasket between the structure and the resilient channel / cross batten.

Acoustic Flooring

The principle of decoupling comes into play here. This material is used to decouple the main floor surface from the subfloor, and thus reduce noise transmission. Common materials for acoustic flooring include Acoustiblok, rubber based crumb, cork and felt for example.

Soundproof Windows

Specialist types of soundproof windows use the principle of decoupling to reduce the sound that enters or leaves a room where installed. These windows typically have thick glass panes and a layer of air trapped in between each layer.

Soundproof Doors

This is another type of architectural soundproofing solution. Much like soundproof windows, soundproof doors are designed to use the principle of increased depth and mass as well as decoupling to reduce sound transmission.

Acoustic Panels

These panels are another type of sound absorption board, commonly referred to as AcoustiCloud Panels and AcoustiWall Absorber Panels and are installed invariably on the surface or near the surface of ceilings and walls. Again these are used more so for controlling internal acoustics to equalise and calibrate. They are reasonably effective when positioned correctly and cover sufficient volume and surface area as well as being aesthetically pleasing on the eye. Acoustic panels are seen as a decorative alternative to acoustic foam and come in a range of colours, shapes and designs.

Acoustic Fabrics

Typically used for theatre curtains, blackout curtains and studio blankets, acoustic fabrics are a very thick type of fabric which are effective when it comes to dealing with acoustics in large rooms or halls. They are also used as a wall lining to increase acoustic equalisation within rooms such as cinemas.

Acoustic Foam

Acoustic foam, also commonly known as Studio Foam, is wall mounted foam panels that can be flat, chamfered, convoluted, wedged or have pyramidal shapes protruding from them. They mostly help to improve audio quality in studios and music rooms. Acoustic foam works on the principle of sound absorption and re-calibration of internal acoustics, and so they are not as effective as other materials when it comes to blocking sound. They should make a noticeable difference to internal acoustics and the audible values, but if you are looking for a sound blocking solution, there are far better materials you should consider. It’s important to note that the thickness and densities of these foams vary, which in conjunction with correct positioning, plays a significant part in their effectiveness and performance. You should also take into account the type and amount of surface area to be covered.

30 Best Soundproofing Materials

Soundproofing materials come in all forms and kinds, as we have already outlined. However, it is important to be aware of how and where they should be applied for best results. Needless to say, it’s also important to consider the quality of the particular soundproofing material you intend to use to achieve the very best possible results. Here’s a rundown of the 30 best soundproofing materials available on the marketplace and how best to use them:

1. Acoustic Membrane

There are different types of acoustic membrane on the market, some much heavier than others and some higher performing than others. These will be rated by different dB reduction levels across differing Hz frequencies and are available in different thicknesses. The thicknesses and weight will affect their application and effectiveness, so it’s important to choose well.

• Uses: ideal as a sound insulation membrane as it works well when it comes to reducing sound transference.
• Pros: minimal depth to existing structures such as walls and ceiling, easy to install, long lasting.
• Cons: some are rather heavy with increased mass which in turn provides a contra effect. Some brands are more expensive but as the saying goes, you get what you pay for.

---

2. Acoustic Mineral Wool Cavity Insulation

Mineral, rock or stone wool insulation, such as Acoustiblok QuietFibre, are essentially open cell insulation materials which work very well at absorbing acoustic and thermal energies. Invariably used in cavities such as stud walls, this rather rigid material comes in different thicknesses and densities and is used in both households and commercial projects as it is quite affordable. Not only good at acoustic and thermal energy absorption but almost as important if not more so, it is very useful for filling cavities. This prevents the cavity from being an open and resonant ‘cave’ like hole which can lead to an amplification of acoustic energy. Despite being quite rigid, it is easy to cut.

• Uses: to soundproof walls and ceilings, make acoustic panels and bass traps, and as soundproofing insulation in various places, from residential to commercial spaces.
• Pros: affordable, natural material, fire and moisture resistant.
• Cons: need a lot of depth of the material to be effective by itself. Protective breathing gear must be worn as cutting causes slivers which lodge in the skin, or may be inhaled and irritate the lungs.

---

3. Fibreglass

Soundproof fibreglass comes in boards / slabs rather than rolls and can be used in various places and applications including to make acoustic panels in home studios, theatres and commercial buildings. This soundproofing material is very effective in diminishing noise that enters or leaves a room, and also improves internal acoustics. There are different types which you can choose from with differing thicknesses, densities and strengths. For example 703 boards are best for reducing high frequency noises whilst 705 boards are more suited to low frequency bass noises.

• Uses: in recording studios, home cinemas, theatres and anywhere where soundproofing is needed, extremely versatile.
• Pros: suitable for various frequency ranges, come in different thicknesses, easy to cut.
• Cons: known to be an irritant so protective gear must be worn when handling.

---

4. Resilient Channels

Resilient sound channels are the main way of decoupling drywall from internal structures of buildings. This system can also be installed with acoustic hangers or gaskets which further reduce the vibration. Resilient sound channels are strips of metal or timber that are installed to the walls so that the soundproof insulation within the walls can be kept firmly in place, whilst providing a platform onto which all finishing systems can be attached. This eliminates the direct contact that there would otherwise be through the layers of structure – walls, ceiling, floors. Screws can pass through several holes or gaps found in these channels to ensure easier screwing, making them easy to install. Any sounds that pass through will basically keep vibrating against the resilient sound channels, and so they are isolated from the room.

• Uses: generally used during construction as they help to achieve very good soundproofing in a building due to decoupling principles.
• Pros: relatively easy to install, come with practical gaps/holes
• Cons: low cost, will take considerable time to install if there’s a large surface area to cover.

---

5. Acoustic Hangers (Mounts)

Sound isolation clips are designed to allow a decoupling separation between the walls and ceiling from the underlying framing studs and joists. These moulded rubber and steel isolation clips are used to control sound and are designed to reduce vibration through a structure.

• Uses: in wall, ceiling and floor applications for treating both airborne and impact noise.

---

6. Soundproof Drywall (Plasterboard)

Apart from the common varieties of drywall which can be purchased at most DIY stores, there is also a more specialised form of drywall, namely soundproof drywall. This comes in different thicknesses, and promotes having an increased sound transmission class than the other types of common drywall used in everyday construction, due to its increased density and mass. Soundproof drywall typically combines several layers of gypsum boards, along with steel, with the main aim being to increase its density and mass so as to block sound effectively. Having said that, any type of drywall can work well for soundproofing as long as decoupling is at the back of one’s mind. To achieve good results in terms of soundproofing, it is important to choose thick drywall in conjunction with some other soundproofing methods, such as Acoustiblok 3mm Isolation Membrane, sealants, tapes and caulks for example.

• Uses: can be used in any building or room
• Pros: quite effective
• Cons: increased weight over effect, expensive option, requires professional installation

---

7. Dense Board (OSB, Plywood, Particle Board, Fire Board)

OSB or Oriented Strand Board is a versatile and durable building board. An alternative, plywood can be used as the construction is similar with multiple layers of opposing-oriented wood fibres that creates rigidity and strength with increased mass and density.

8. Soundproof Floor Underlay

Floor underlayments are a great way to reduce sound transmission that naturally occurs between engineered floors and hardwoods. There are different kinds of soundproof floor underlayment but felt underlayment is among the most popular options for floors of various kinds, including laminate floors, hardwood and engineered wood. They are typically made from fibres which are compressed and treated with heat, so as to form a dense sound absorbing material. A great example of this is Acoustiblok AcoustiWool Acoustic Underlay, which comes available in rolls and works best if installed in conjunction with Acoustiblok Isolation Membranes.

• Uses: ideal for most kinds of wood or engineered floors in both residential and commercial premises.
• Pros: quite affordable, easy to install, hardwearing and effective at absorbing sound as well as moisture.
• Cons: simply an acoustic underlay and will only offer a moderate level of acoustic performance.

---

9. Anti-Vibration Soundproof Floor Mats

Soundproof floor mats are another interesting option to arrest impact sound and vibration leading to structural airborne noise. It is a known fact that certain appliances and machines create a lot of vibration and noise. Anti-vibration soundproof mats help to kill annoying humming sounds and vibrations. These types of mats are effective at reducing noise, and since they eliminate vibration they are also ideal for installation beneath and inside machinery and appliances, as well as to soundproof cars. They can also offer a level of acoustic absorption on a surface or within a room to help reduce unwanted regeneration/resonance and enhance high-end audio performance.

• Uses: beneath or behind appliances or machines, to reduce the transmission of noise and vibrations.
• Pros: simple and effective soundproofing solution when the source of the noise is from machines or appliances.
• Cons: ideally used in conjunction with other soundproofing methods for best results.

---

10. Acoustic Sealants

Acoustiblok Acoustical Sound Sealant is one of a number of well-known brands on the marketplace that is most renowned as a reliable soundproofing compound which works on the principle of decoupling.. It comes in dispensing tubes like sealant products, and so is very easy to apply. This product is meant to be used as a sound dampening method that maintains Sound Transmission Class (STC) in applications where required, yet remains permanently flexible. It is mostly used during the construction of walls that require soundproofing as it can be applied directly between layers of differing materials, Acoustiblok Isolation Membrane, drywall or plasterboard. It works to dissipate sound vibrations that would otherwise manage to pass through walls. Essentially this is a form of sealant that reduces leakage considerably and can be used on countersinking the heads of mechanical fixings.

• Uses: used on walls and ceilings as well as any gaps or open spaces such as seams, seal holes and screw holes.
• Pros: a product that is easy to apply, affordable and quite effective, eco-friendly
• Cons: a complementary soundproofing option and will not soundproof a room in isolation

---

11. Acoustic Caulk

A complementary soundproofing solution which is intended to seal overlaps of materials, fill small gaps, cracks, or spaces in a room. Sound can travel through even the smallest areas, and so it is important to seal off a room completely for the best possible results. Acoustic caulk is a must where plasterboard or drywall is installed to reduce possible weakness but should not be relied upon to achieve acoustic levels by themselves. Areas like corners between walls, lines where walls and ceilings meet, and doors and windows must be completely sealed.

• Uses: to fill any gaps easily to ensure best soundproofing results
• Pros: inexpensive, easy to apply
• Cons: a complementary soundproofing option and will not soundproof a room in isolation

---

12. Acoustic Putty

Flexible acoustic and intumescent putty is designed to maintain a building separation and wall partitions structural integrity and acoustic properties. AcoustiPutty pads are designed to maintain the integrity and acoustic properties of flexible wall assemblies.

• Uses: suitable for most flexible wall partitions constructed from timber and steel studs with all types of finishing board. For acoustic, fire and insulation resistance.
• Pro: quick and easy to apply, fire resistant
• Cons: a complementary soundproofing material and will not soundproof a room in isolation

---

13. Acoustic Plaster

Like acoustic plasterboard, acoustic plaster finishes have been around for years. Varying ingredients, compounds and systems can increase or decrease weight and flexibility to further reduce surface reflections and in doing so help with equalisation of the internal acoustics.

• Uses: shopping centres and theatres, universities, restaurants, office spaces, entrance halls, museums, libraries, dining areas as well as some very exclusive private residences.
• Pros: can further help to reduce surface reflection and resonance.
• Cons: although increased depth and weight can add to deflection of sound waves, these are invariably used for increased acoustic calibration.

---

14. Soundproof Spray

Soundproof or sound deadening spray is used mainly for spot treatments. Floor mats for example, may have been installed to reduce unwanted noise yet microscopic gaps between the matt and the adjoining surface can still allow vibrations to occur. Using a sound deadening spray will minimise those gaps and as such one would expect some improvement on overall acoustic performance, – the saying, ‘every little counts’ could be applied here.

• Uses: used mostly in doors, car boots and compartments
• Pros: easy to apply, quite effective
• Cons: a complementary product only to improve soundproofing performance

15. Soundproof Paint

Soundproof paint, sometimes also referred to as sound deadening paint, is exactly what it says on the tin! As a paint it can be applied either by means of a roller or sprayed on. The concept is that the thicker the layer of paint, the better the result. Spraying will naturally lead to a thicker coating and so it is generally the recommended method of application for soundproof paint. Having said that, soundproof paint is not the most effective soundproofing method and won’t produce significant results. Due to its lack of mass once applied, the resulting soundproofing effects can be mixed. Since it contains latex, similar to rubber, it is definitely better to apply rather than regular paint where breathability of the wall is not a concern. Latex has a tendency to settle into cracks, just like silicone caulk, so will perform better than standard water-based paints, although again is non breathable.

• Uses: applied to walls to reduce sound transmission
• Pros: simple and affordable option
• Cons: not the most effective of methods as it does not rely either on the principle of mass nor decoupling.

---

16. Soundproof Wallpaper

Like soundproof paint, it is highly debatable whether soundproof wallpaper can effectively soundproof a room, especially when used in isolation. Mass is one of the main principles of soundproofing, so it is difficult to have a thickness considered adequate by using just wallpaper. Soundproof wallpaper is generally made from closed-cell polyethylene foam. This has very good sound absorbing properties, so soundproof wallpaper can and should act like an acoustic absorbing layer but as it is so thin the effects are minimal at best but again the saying, ‘every little counts’ could be applied. Since soundproof wallpaper comes in an assortment of designs, it is obviously more aesthetically pleasing that acoustic foam, and much easier and less invasive to install.

• Uses: can be used in any setting, both residential and commercial
• Pros: easy to apply, comes in rolls, works reasonably well for soundproofing purposes, aesthetically pleasing.
• Cons: actual efficacy is questionable so consider using alongside other soundproofing methods to improve results.

---

17. Acoustic Wall Covering

Acoustic wall covering is a sheet material made from composite fabric layers. A flexible hybrid composite that is strong, yet highly compressible and soft at the same time. It is installed onto the internal surface of a wall to offer great results in acoustic calibration (softening) and acoustic isolation (conversion).

• Uses: can be used in residential and commercial spaces, including engine rooms and any heavy industrial facilities where there’s a lot of noise
• Pros: innovative material that is flexible but durable, easy to apply, effective option
• Cons: rather expensive

---

18. Acoustic Glass (Soundproof Windows & Frames)

Worth mentioning that whatever approach one undertakes, it is only as effective as its weakest point. Acoustically rated windows are specially designed windows that are ideal for soundproofing purposes. Since these windows are constructed to include multiple layers of glass, with each being quite thick, the amount of sound that enters or leaves a room is minimal. For improved results, such windows would incorporate air or inert gas, that is trapped in between each glazing panel to further effect movement of acoustic waves. Soundproof windows are effective and they can even be installed right over the top of existing windows as necessary.

• Uses: ideal for those who experience a lot of external noise, such as traffic and city noise
• Pros: effective soundproofing option
• Cons: relatively expensive

---

19. Soundproof Doors / Frames

Once again it is worth mentioning that whatever approach one undertakes, it is only as effective as its weakest point. Soundproof doors are of increased thickness, sturdy construction, designed to effectively block sound from entering or leaving a room. Double door principles can also be a realistic method should the increased acoustic values and space be available to do so. Well-fitting doors and frames with effective use of gaskets will of course be an important part to any success. Such sound-blocking doors include rigid steel doors, solid-core doors, and other materials where mass is high, and their subsequent weight. In such doors you will not find any openings like mail flaps or pet doors, because the emphasis on soundproofing cannot be minimised by making way for any gaps whatsoever. Fire doors are a good example of soundproof doors.

• Uses: ideal for houses or premises which are situated on busy roads to minimise the amount of noise pollution entering the building
• Pros: effective soundproofing option, sturdy
• Cons: costly

---

20. Door Seals, Sweeps & Gaskets

Weatherstripping tape, door seals and sweeps are available in all sizes and are usually made from rubber and act as gaskets, similar to many draft stoppers. These are attached to the door frame or bottom section of doors, in order to seal gaps between the door and door stop or frame, or door and the floor. Rubber seals include hollow rubber weather-stripping tapes which compress whenever a door or window is shut, thus forming a tight seal. Rubber sweeps tend to scrape against the floor whenever a door is open or closed and there are also sweeps which come in the form of a very dense brush. Also a useful approach on an internal door can be to increase the size and thickness of the door stop or beading around the perimeter. This increases the surface area of the door closing onto the door stop and can also increase the width of draft gasket that can be used.

• Uses: mainly used in door frames, to complement improved sound absorption in conjunction with other soundproofing methods.
• Pros: inexpensive, quite effective
• Cons: intended as a minor solution to soundproofing, other methods of soundproofing will need to be used for increased results.

---

21. Acoustic Foam

Ideal for sound absorption, acoustic foam is available in a wide range of thicknesses as well as sizes and colours. There are many brands names that sell acoustic foam. Some even offer this material in appealing colours as some customers look for the aesthetic appeal of this product aside from its practical value.

• Uses: to improve audio quality in a room. As a result, acoustic foam is used for this purpose as well as to reduce sound leakage. Often found in games rooms, home theatres, music rooms and recording studios.
• Pros: ideal for improving sound quality in a room, helps to reduce noise pollution, can improve the design appeal of a room or space.
• Cons: doesn’t perform well at preventing sound transference from room to room, some foams can be flammable

---

22. Sound Absorber Panels

Sound absorbers are available in many styles and types, most of which come in appealing colours. When installed, they can also make a room or space look more visually appealing. These types of Absorber Panel such as Acoustiblok Quiet-Cloud, AcoustiWall can be mounted to ceilings and to walls as it helps to cut down on acoustic reflections and sound reverberations. That is why it is called sound ‘absorber’ as it works on the principle of sound absorption.

• Uses: ideal for recording studios, cinemas, theatres, classrooms, games rooms, gymnasiums and entertainment areas.
• Pros: quite effective and affordable method if your main intention is sound absorption and improving acoustics in one room and aesthetically pleasing.
• Cons: can be expensive, needs calculating and installing correctly for maximum calibration and limited performance for sound isolation.

---

23. Acoustic Ceiling Systems & Tiles

Directly fitted to a ceiling or used as a structural drop ceiling to create a grid system, acoustic ceiling tiles are similar to acoustic panels to provide effective acoustic control. Available in a wide variety of materials, sizes, depths and designs. Acoustic ceiling tiles are an easy solution for improving the acoustical qualities of any space.

• Uses: in soundproofing ceiling spaces to create a finished ceiling with a void above in which to house services, HVAC ducting etc.
• Pros: allows a large surface area of acoustic absorption and creates a finished ceiling.
• Cons: structural framing system sometimes on wire or steel drop rods to the above structure to create a grid work for the tiles to lay which needs professional installation.

---

24. Soundproof Curtains

Soundproof curtains, sometimes referred to as blackout curtains or acoustic curtains, are widely used to reduce noise passage as a temporary partition or privacy material, such as backstage at a theatre. When hung in strategic positions the thick fabric greatly reduces the spread and movement of sound waves within an area which reduces unwanted sound from travelling from space to space.

• Uses: in theatres, nurseries, bedrooms and home theatres.
• Pros: high quality material that is long lasting, helps to block sound as well as improve acoustics in a room.
• Cons: most fabrics are costly due to their thickness and the fact they need to be made to measure.

---

25. Soundproof Blankets

Soundproof blankets are used in various cases where sound absorption needs to be attained and offer a low-cost alternative to relatively expensive soundproofing solutions. In fact, soundproof blankets are probably the most practical option for someone on a tight budget who wants a temporary and moveable solution. They are made from thick, plush fabric which is designed to absorb sound and prevent acoustic transference.

• Uses: these blankets can be hung to walls or over doors and windows.
• Pros: relatively affordable, easy to install.
• Cons: are a localised solution but certainly not as effective as full and complete coverage of an area with more advanced soundproofing methods

---

26. Furniture & Finishings

Unsurprisingly, furniture and other household items can play an important role in soundproofing. In some rooms, you might experience more sound reverberation than others. This can be a nuisance yet funnily enough, can sometimes be resolved by simply moving your furniture to better sound dampening positions. You could also try adding lining to walls, such as tapestries or fabrics, as well as make use of sofas and large soft cushions. If specific walls are thin, it’s recommended you place heavy pieces of furniture against them, such as a wardrobe or a wooden bookcase full of books to dampen the sound.

• Uses: a basic means of reducing sound reverberations or low-level noise travelling between thin walls
• Pros: quick and easy fix, inexpensive
• Cons: limited results can only be expected

---

27. Acoustic Fencing (External)

Acoustic fencing is essentially an acoustic barrier or noise insulator for outside spaces. It’s ideal for those who want an effective solution to block external sounds and noises. Establishing correct height and length of fence is essential to create the necessary angles of incidence for maximum effect. Acoustic fencing can tackle noise from road traffic, trains and railway tracks, and any noise from neighbouring plots. Some fencing solutions will be as expected, constructed from thick, dense materials to work principally on mass and density to block line of sight. These types of fence are great where a new structure has to be built although quite time consuming and expensive due to the amount of material and labour involved in their erection. However, where a fence structure is already in evidence but not performing quite as well as one would like, there is also a material known as AcoustiFence. This flexible membrane is designed to attach to an existing fence structure such as a post and rail or even chain link to increase performance. Available in rolls of material and very easy to install with minimal labour offering a further saving on cost. The material is essentially a membrane, and it can be hung or secured in place to post and rail, to lattice or attached to a timber frame, depending on the individual case. Installation of soundproof fencing is fairly quick, easy and effortless.

• Uses: can be installed to perimeter fences, chainlink, hoardings to block sounds entering from adjoining plots
• Pros: very effective soundproofing option in areas of high noise pollution such as busy cities, noisy neighbours, and any other exterior environment which is causing noise pollution
• Cons: Typical rigid construction, quite costly due to materials and labour.

---

28. Acoustic Absorber Panels (External)

As almost all regular absorber panels are compressible and work on the factor of absorption, they tend to also absorb and accumulate moisture which can create an issue when trying to use them externally. Some materials though are hydrophobic. An alternative to these is external acoustic absorbers which are a rigid, durable panel made from recycled glass beads with an appearance of a lightweight granite / stone. Offering good resistance, they produce a sound absorbing, impact resistant panel solution which is not affected by liquid or moisture. Also noncombustible, chemically inert and non-fibrous.

• Uses: external where unwanted noise reverberates from buildings although can be internal especially where an element of increased impact resistance is required.
• Pros: good impact resistance and not affected by rain, moisture.
• Cons: relatively expensive but will perform in areas where other solutions struggle.

---

29. Industrial Acoustic Soundproof Panels

These acoustic panels are invariably manufactured from more industrial materials such as steel and aluminium to be employed to mitigate noise sources with higher power and pressure output. Specifically designed to withstand outdoor exposure in full sunlight, extreme weather conditions, and harsh industrial environments (NRC of 1.0 is the highest sound absorption rating possible). Examples like Acoustiblok All Weather Soundproof Panels are a triple core approach to include a perforated facia for diffusion, an internal layer of U.L. classified Acoustiblok 3mm Sound Isolation Membrane material for acoustic conversion plus a specifically engineered 50mm Acoustiblok QuietFibre hydrophobic/weather-proof, open cell, core sound absorbing material.

• Pros: very effective soundproofing option in areas of high dB, sound and power noise pollution such as plant, generators, HVAC and any other external environment.
• Cons: typical rigid construction, quite costly due to materials and labour.

---

30. Acoustic Louvres

Typically, acoustic louvres are used in building openings permitting air to flow, whilst shielding the environment from unwanted noise. As an open shutter with horizontal, curved or linear blades/slats that are angled to admit light and air, but to keep out rain and direct sunshine. The angle of the slats may be adjustable

• Uses: multi-purpose as acoustic screens around mechanical plants where equipment requires airflow.
• Pros: effective at reducing acoustic energy whilst allowing direct flow of air where required.
• Cons: allows for a weakness and a break in any acoustic isolation strategy but essential where needed.

---

Conclusion

Through this article we’ve explained in great detail what soundproofing is, the various types of soundproofing methods and products available on the market. We have also explained which products work best in different scenarios, according to one or more core soundproofing principles. After this thorough overview, we hope that you have achieved a much clearer idea of this detailed subject. If you are currently considering soundproofing your home, business premises, or perhaps a particular room such as a recording studio, home theatre or workshop, hopefully you can now make a well-informed decision on the best soundproofing method and materials to use.