About acoustic comfort in buildings
Acoustic comfort impacts health and well-being
Noise pollution is a widespread environmental concern that can have significant effects on our daily lives, our health, our mental well-being, and our overall quality of life. Acoustic comfort refers to the creation of a conducive environment where unwanted or intrusive noise is minimized.
Studies have shown that a well-designed acoustic environment not only improves concentration and communication, but also reduces stress and sleep disorders. Beyond that, it also promotes a feeling of security and privacy. When we are in an environment where unwanted noise is effectively blocked and where the sounds we want to hear are crystal clear, we see increased productivity and reduced health issues.
In hospitals and healthcare establishments, for example, acoustic comfort is essential. In these environments, which are often experienced as stressful for patients, noise from equipment, conversations and other sources can increase feelings of anxiety and discomfort. A quieter, more peaceful acoustic environment can instead help patients feel more comfortable during their stay, which can contribute to faster recovery.
In the education sector, poor acoustics can affect students' ability to concentrate and learn. Instead, a comfortable acoustic environment with minimal background noise allows them to concentrate better and absorb information more effectively. Clear and intelligible speech is also essential for effective communication between teachers and students.
Another example is the hospitality sector, where a comfortable acoustic environment is essential to ensure guest comfort, privacy and satisfaction, and improves the overall guest experience. Investing in soundproofing and acoustic design can lead to increased customer loyalty, positive reviews and improved brand reputation.
Sources of noise in buildings:
In building acoustics, there are four primary sources of noise that contribute to the overall sound environment:
- Airborne noise from external sources: Sounds originating from outside the building, such as road, rail or air traffic, as well as voices and activities from the surrounding environment.
- Airborne noise from internal sources: Sounds generated inside the building, including conversations, electronic devices, and entertainment systems.
- Impact noise: Noises caused by movements or physical interactions, such as footsteps, moving furniture, or falling objects.
- Equipment noise: Noise generated by mechanical systems and equipment inside the building, such as HVAC systems, elevators, and machinery.
Noise pollution from HVAC systems
Air movement throughout the system can create noise, particularly if the airflow velocity is high. The operation of HVAC equipment such as fans, compressors, blowers and motors can generate noise, especially if the equipment is not properly maintained or operated at high speeds. Finally, HVAC equipment and components can produce vibrations during operation, especially if they are not adequately insulated or come into contact with other surfaces. These vibrations can transmit through building structures, amplifying noise levels in adjacent spaces. Particular attention should also be paid to ducts and pipes.
Noise issues in pipes
Noise issues related to water pipes can be a significant source of disturbance in buildings. The noise generated by sanitary installations often comes from water and air turbulence, especially the impact of water flow on pipe walls, and is transmitted through mounting brackets to the building structure. Areas where acoustic management is particularly critical include points where pipework deviates to avoid structural elements and where pipes bend from vertical to horizontal orientations. Although hearing the sound of running water in building pipelines does not necessarily indicate a problem, it can still be annoying for occupants. Depending on factors such as pipe material and encapsulation with gypsum board, the noise level can vary. Furthermore, the sound of running water can be amplified and transmitted through certain building areas when pipes are in direct contact with each other or with supporting structures, floor, or wall partition materials.
Noise issues in ducts
Noise issues in ventilation and air-conditioning systems can arise from various sources, including the equipment itself and the airflow circulating through the system. One primary source of noise is the transmission of noise directly from the ventilation or air-conditioning system. Additionally, vibrations from machinery within the system can contribute to noise disturbances, as can the transmission of noise through the building structure due to vibration. Furthermore, the circulation of air within the ducts can generate noise, particularly when airflow speeds increase. Noise transmission via grilles and diffusers also plays a role in the overall acoustic environment. This phenomenon is even more accentuated when the internal surface of the ducts is made of materials, such as metal, which easily reflect sound.
Insulation can help prevent acoustic issues in HVAC systems
Acoustic characteristics of mineral wool
Mineral wool has intrinsic acoustic properties for effective insulation solutions. These include airflow resistivity, dynamic stiffness, and sound absorption, all of which contribute to its performance in noise reduction applications. Airflow resistivity, determined by the friction between mineral wool fibers and air particles, affects the material's ability to reduce transmitted acoustic energy. Ideally between 5 and 50 kPa s/m², it depends mainly on the length and diameter of the mineral wool fibres.. Dynamic stiffness characterizes the ability of mineral wool to dampen noise and vibrations, as determined by standardized tests. Sound absorption converts part of the acoustic energy that hits a surface into heat, which attenuates the incident sound. It depends on various factors, including airflow resistivity, frequency, and material geometry. Mineral wools have high absorption coefficients, with sound energy easily penetrating through their surface.
Choose the right acoustic insulation solutions for HVAC systems
For HVAC systems, sound insulation and sound absorption both play a crucial role in mitigating noise pollution. Sound insulation involves reducing the transmission of noise through the walls of duct and pipe into occupied spaces. Effective insulation materials, such as mineral wool, can significantly attenuate noise levels, creating quieter and more comfortable indoor environments. On the other hand, sound absorption involves the absorption of sound waves within the HVAC system itself, preventing reverberation and echoes that can contribute to overall noise levels. By incorporating sound-absorbing materials into ductwork and equipment, acoustic comfort can be further improved and noise pollution from HVAC systems minimised.
Our acoustic insulation solutions
Our acoustic insulation solutions for ducts:
CLIMLINER for internal duct insulation
CLIMLINER is a reliable solution for enhancing the acoustic insulation of metal air ducts. This lightweight glass wool slab, featuring a black glass tissue facing, provides sound absorption while insulating HVAC equipment. Moreover, CLIMLINER ensures durability and resilience and protects against corrosion. For combined thermal and acoustic insulation needs, CLIMLINER Slab CLEANTEC is a high-performance solution with durable glass fabric facing, offering optimal acoustic absorption and thermal insulation.
CLIMAVER® - the innovative all-in-one solution
CLIMAVER® is an all-inclusive solution for duct systems, made from dense and rigid glass wool boards. CLIMAVER® self-supporting air ducts provide a cost-effective and easy-to-install alternative to traditional insulated metal ducts, ensuring state-of-the-art insulation and comfort. In addition to its various other benefits, CLIMAVER® also prioritizes acoustic comfort, with high absorption even at low frequencies, eliminating the need for additional acoustic insulation liners or sound attenuators.
Our acoustic insulation solutions for pipes
U PROTECT® Pipe Sections and CLIMPIPE
U PROTECT® PIPE SECTIONS are a convenient all-in-one insulation solution for building pipe systems. In addition to offering best-in-class thermal insulation and fire protection, they also minimize sound transmission from pipes, and contribute to a quieter environment for occupants. With their unique properties of higher elasticity and lower density, they provide effective soundproofing compared to conventional insulation materials.
CLIMPIPE, a glass wool alu-faced pipe insulation solution, offers lightweight, incombustible and easy-to-install thermo-acoustic comfort for pipe systems. With its acoustic properties, CLIMPIPE effectively reduces noise transmission through ducts and pipework, ensuring a quieter environment for occupants.
A bit of acoustics theory
What is sound pressure?
Sound pressure, measured in decibels (dB), reflects the amplitude of a sound wave, defining the volume of a sound. A stronger amplitude produces a louder sound, while a weaker amplitude results in a quieter sound.
What is frequency?
Sound frequency refers to the rate of pressure variations per second and is measured in hertz (Hz). For instance, a frequency of 1 Hz represents one wave cycle per second, while 20 Hz indicate 20 cycles per second. The frequency of a sound determines its pitch, with lower frequencies producing low-pitch sounds and higher frequencies producing high-pitch sounds. The range of frequencies audible to humans spans from 20 to 20,000 Hz. It is known as the audio spectrum.
What is the difference between sound insulation and sound absorption?
Sound insulation focuses on minimising the transmission of sound between different rooms or spaces within a building. It prevents sound from traveling through walls, floors, or ceilings, thereby reducing the noise heard in adjacent areas. On the other hand, sound absorption targets the reduction of sound propagation within the same room. This is achieved through the use of absorbent materials which absorb sound energy, preventing it from being reflected from surfaces and creating echoes or reverberation.