How to Enhance Acoustic Comfort with Rockwool Insulation

The importance of soundproofing solutions cannot be overstated. Rockwool insulation stands as a high-quality solution against intrusive noise. It offers a quiet space for all settings, whether it be a bustling office or a family home.

In this guide, we look into enhancing acoustic comfort with Rockwool insulation. We explore its effectiveness, installation techniques and the transformative impact it provides for all environments.

What is the rating for acoustic insulation performance?

You can evaluate the effectiveness of Rockwool acoustic insulation by understanding the industry-standard ratings used to measure their performance. Here, we explore the key requirements for top-performing Rockwool sound insulation. 

1. Sound Transmission Class (STC) Rating

Assess the insulation’s ability to prevent airborne sound transmission through walls, floors and ceilings with the STC rating. Achieve higher STC values (ranging from 25 to 80) by using insulation products with enhanced sound-blocking properties. 

You can reach airborne STC ratings of up to 65 when a Rockwool sound insulation slab (with a density of 60 kg/m³ or higher) is installed in wall cavities. 

2. Impact Insulation Class (IIC) Rating

Examine the effectiveness in reducing impact noise such as footsteps with the IIC rating. Higher IIC values (typically ranging from 25 to 72) are needed to experience superior impact noise reduction. 

By integrating Rockwool floor insulation (with a density of 100 kg/m³ or higher) into floor assemblies you can enjoy impact noise reduction of up to 33 decibels (IIC rating).

3. Noise Reduction Coefficient (NRC)

Determine sound-absorbing capabilities with the NRC, a value ranging from 0 (no absorption) to 1 (complete absorption). You can maximise acoustic comfort by selecting insulation with higher NRC ratings, effectively controlling reverberation and echo within a space.

You can create an environment in noise-sensitive spaces like home theatres and music rooms with Rockwool's ability to absorb a broad range of frequencies (from 125Hz to 8000Hz). Ensure clear and accurate sound reproduction by minimising unwanted echoes and reverberation. 

4. Sound Absorption Coefficient

Evaluate sound absorption across different frequencies with the sound absorption coefficient. Ensure optimal acoustic resistance by choosing insulation solutions with high absorption coefficients. Rockwool's remarkable sound absorption coefficients range from 0.85 to 1.00 (at frequencies between 250Hz to 4000Hz), to neutralise sound waves effectively. 

Rockwool's open-fibre structure (with pore sizes ranging from 2 to 6 micrometres) and high density (ranging from 40 to 180 kg/m³) help maximise sound-dampening capabilities.

5. Reverberation Time

It measures the time required for sound to decay by 60 decibels within an enclosed space. You can achieve desired reverberation times (ranging from 0.4 to 1.2 seconds for speech intelligibility) by using insulation materials with sound-absorbing properties.

Tailor acoustic performance by selecting the appropriate Rockwool insulation density (from 40 to 180 kg/m³) and thickness (ranging from 25mm to 200mm) for your noise control requirements. Benefit from product options including batt, roll, board and customised solutions like acoustic panels for ceiling and wall spaces.

Does Rockwool acoustic performance differ between different types of insulation?

Yes, Rockwool's acoustic performance can vary depending on the insulation type. Factors such as density, thick dimensions and design influence its effectiveness. Discover how each insulation type delivers tailored sound absorption, noise reduction and acoustic control solutions. 

Batts and blankets

Explore the exceptional soundproof properties of Rockwool batts and blankets. They deliver acoustic performance in irregularly shaped spaces. Experience their flexibility to contour seamlessly around obstacles, corners and curves.

NRC ratings range from 0.90 to 1.05, unlocking exceptional sound absorption across a wide frequency range. Plus, achieve STC ratings up to 63 to ensure airborne noise reduction between adjacent spaces.

Boards and slabs

Lay high-density Rockwool acoustic insulation slabs and boards to create robust barriers against airborne noise transmission. Their rigid and dimensional stability helps to achieve precise acoustic isolation between adjacent spaces.

They offer unrivalled sound-blocking with STC ratings reaching an impressive 68, creating robust barriers against airborne noise transmission. Also, IIC values reach up to 50, effectively minimising impact noise.

Insulation rolls

Experience seamless sound absorption with continuous coverage offered by a Rockwool insulation roll. Eliminate potential sound bridges and maintain uniform acoustic control by minimising joints or seams within the insulation layer.

Overall, NRC values reach up to 1.00, delivering uniform sound absorption throughout large areas. Plus, STC ratings hit as high as 66 to ensure superior acoustic isolation and privacy within the insulated space.

Loose-fill insulation

Discover the acoustic versatility of loose-fill Rockwool insulation for intricate cavities and hard-to-reach spaces. Leverage its superior sound-dampening capabilities to control reverberation and echo in irregularly shaped structures. 

NRC ratings potentially up to 1.10, adhering effortlessly to intricate cavities and hard-to-reach spaces. Also, reduce reverberation times to as low as 0.4 seconds for optimal speech intelligibility.

Curtain batts

Embrace the flexibility of Rockwool curtain batts as movable acoustic barriers, offering adaptable noise control solutions on demand. These highly effective sound-absorbing panels help create temporary acoustic partitions or modify room acoustics. These movable acoustic barriers can achieve NRC values ranging from 0.85 to 1.05. Plus, gain STC ratings up to 33.

Pipe and vessel insulation

Silence disruptive mechanical noise by encasing pipes and vessels with specialised Rockwool pipe insulation products. Benefit from their exceptional ability to mitigate equipment noise and vibrations. 

Tackle equipment noise and vibrations with potential NRC ratings up to 1.10. STC ratings can also reach 28 which meets stringent acoustic performance standards. 

How to install Rockwool acoustic insulation

Each step plays a crucial role in boosting sound absorption, noise reduction and overall acoustic comfort. Follow this comprehensive guide of top tips for installing Rockwool mineral wool insulation.

1. Achieve full cavity fill

• Whether using floor or Rockwool wall insulation, ensure no air gaps remain. Cut Rockwool batts to fit tightly within cavities. This eliminates potential sound leakage paths.
• Leverage Rockwool's flexibility to compress the insulation slightly. It creates a friction fit that seals the cavity while maintaining its sound-absorbing properties.
• Gaps or voids act as conduits for sound transmission, compromising acoustic integrity.

2. Seal all penetrations

• From electrical boxes to plumbing pipes, seal any penetrations with acoustic sealant. As a result, this creates an airtight barrier.
• Prevent flanking noise from travelling through these openings. Maintain the integrity of your acoustic insulation system and preserve acoustic isolation.
• Even the smallest unsealed gaps can hinder its effectiveness. 

3. Create continuous insulation

• Install Rockwool insulation as a continuous layer without gaps or breaks. It ensures uniform sound absorption and noise reduction.
• Avoid gaps that could create potential sound bridges. They compromise the overall acoustic performance and allow sound to bypass the insulation.
• Continuous insulation maximises the material's ability to dampen sound waves.

4. Introduce resilient channels

• Enhance airborne noise reduction by installing resilient channels. Add the channels before fitting Rockwool cavity wall insulation to wall cavities.
• Separate the drywall from the framing. This minimises the transfer of vibrations and improves acoustic isolation between adjacent spaces.
• The simple yet effective technique amplifies the noise-blocking capabilities of your insulation system.

5. Stagger insulation joints

• When insulating adjacent wall or floor cavities, stagger the insulation joints to prevent direct sound paths.
• Prevent sound from flanking through these potential weaknesses. This further enhances the acoustic integrity of your space.
• Staggered joints act as an additional barrier. They ensure maximum noise reduction and acoustic comfort.

6. Proper framing techniques

• Introduce staggered stud or double-stud framing techniques. This creates additional air spaces and improves sound isolation between adjoining spaces.
• Rockwool's excellent sound-absorbing properties control noise transmission through these layered assemblies.
• Combined with Rockwool's acoustic properties, advanced framing techniques create a barrier against unwanted noise.

Can you maintain Rockwool acoustic insulation?

It is important to preserve superior sound-insulating capabilities through proactive care and upkeep. Below is a comprehensive guide on the essential practices that will safeguard your insulation. 

Protect from moisture (annually)

Ensure proper waterproofing measures such as vapour barriers are in place to protect from external moisture. Promptly address any leaks, flooding or water infiltration to prevent the insulation from becoming saturated. After water incidents, thoroughly inspect the affected areas and replace any damaged or waterlogged insulation.

Carry out inspections (annually)

Visually examine the insulation for signs of damage that could compromise its acoustic performance. Check for gaps, tears or areas where the insulation may have shifted or settled, creating potential sound bridges. Annual inspections allow you to address any concerns and ensure seamless acoustic coverage. 

Address mechanical damage

Quickly fix or replace any areas that have sustained mechanical damage, such as tears or punctures. Damage can create openings or weak points, allowing sound waves to pass through. Create seamless acoustic coverage by restoring the insulation's integrity and tackling potential sound bridges. Depending on the damage, consider replacing sections.

Verify airtightness (annually)

Inspect seals, gaskets and sealants used in conjunction with Rockwool insulation to ensure airtightness. Over time, these components can develop gaps, allowing flanking noise to bypass the insulation. Reseal any openings or gaps that may have developed using appropriate acoustic sealants or gaskets. 

Rockwool vs PIR: Which is best for acoustics?

When it comes to acoustic performance, Rockwool insulation stands as the superior choice. While polyisocyanurate (PIR) insulation offers lightweight installation and moisture resistance, its acoustic capabilities fall short. 

PIR insulation upholds modest STC ratings, ranging from 45 to 55, offering less airborne noise reduction. Its closed-cell structure offers a degree of sound dampening. However, it exhibits lower sound absorption coefficients, limiting its ability to control reverberation and echo within a space. 

Combustibility concerns may also require additional fire-rated assemblies. This increases construction costs and complexity. For projects prioritising acoustic properties, Rockwool insulation is superior, delivering unrivalled sound absorption and noise reduction. However, if lightweight installation and moisture resistance are paramount, PIR insulation provides a viable alternative.