Acoustic comfort is an essential element of well-being in living and working spaces. Bio-based materials, derived from renewable resources, offer effective solutions for improving building acoustics while respecting the environment.
Understanding acoustic comfort
Acoustic comfort is defined by the sound quality of a space, which directly influences the health and well-being of its occupants. High noise levels can cause stress, sleep disturbances, and decreased concentration. For example, in school cafeterias, noise levels can reach up to 90 decibels, equivalent to the noise of a highway, posing risks of auditory fatigue and learning difficulties.
Bio-based materials: a suitable solution for managing acoustic comfort
Bio-based materials, such as wood, hemp, straw, cork, and cellulose insulation, have remarkable properties that improve the acoustic comfort of a building. Their natural structure allows them to effectively absorb and diffuse sound, thereby reducing noise pollution.
Wood
Used for centuries in construction, wood is valued for its aesthetic and acoustic qualities. In the form of strips, panels, or fibers, it is used for sound insulation in walls, ceilings, and floors. Wood wool, for example, offers performance comparable to traditional insulation materials while also being environmentally friendly.
Hemp
Hemp is used in concrete form for wall coverings. In terms of airborne sound insulation, however, hemp performs well below traditional concrete or cellular concrete due to its density (300-350 kg/m³), which is much lower than that of traditional concrete (2,300 kg/m³).
Cork
Made from cork oak or recycled cork stoppers, cork is available in panels or rolls. It is particularly effective for soundproofing floors, especially against impact noise. Cork underlayments ranging from 2 to 50 mm thick can reduce impact noise by up to 20 dB. Like wood wool, cork can also be used as an absorbent material to control interior reverberation in spaces.
Straw
Straw is increasingly used in construction, particularly for exterior insulation or wall filling. Contrary to popular belief, straw provides satisfactory acoustic insulation, with sound attenuation performance suitable for facade insulation. Typically, 150 kg/m³ straw blocks with 20-30 mm clay plaster will give an RA,tr performance for a 320 mm wall of between 40 dB and 45 dB, making straw suitable for acoustic insulation of facades.
cellulose insulation
cellulose insulation, made from recycled paper, is a bio-based insulation material offering excellent acoustic performance. Thanks to its dense fibrous structure, it effectively absorbs airborne noise (voices, traffic) and impact noise (footsteps, vibrations), reducing noise pollution and reverberation. For example, a density of between 30 and 50 kg/m³ is recommended for optimal sound attenuation and absorption results. A study conducted by CEREMA evaluated the acoustic properties of bio-based materials, including cellulose insulation this report indicates that cellulose insulation effective sound attenuation, significantly reducing airborne noise such as conversations and external noise pollution. In addition, its vibration absorption capacity helps to reduce impact noise, thereby improving the acoustic comfort of interior spaces.
Other advantages of bio-based materials
Currently, there is no official definition for bio-based materials. This means that materials containing only 1% bio-based raw materials can freely claim to be bio-based. That is why, in our example, we define "bio-based materials" as materials with a "Bio-based Product" label containing at least 70% bio-based material.
Carbon footprint:
Bio-based materials reduce the carbon footprint of buildings and preserve natural resources. Because their raw materials come from biomass, they also act as carbon sinks and continue to store carbon in the building throughout their entire lifespan.
Hygroscopic properties:
Bio-based materials have hygroscopic properties that enable them to maintain comfortable air conditions inside buildings. They can absorb excess moisture from the atmosphere, store it, and release it when the air becomes drier. This characteristic helps maintain a comfortable humidity level in the building.
Read also: Hygroscopic materials: our comprehensive guide
Thermal performance:
In addition to their acoustic properties, they provide effective thermal insulation, contributing to the overall comfort of buildings. They also make a difference during hot weather, providing real comfort in summer.
Practical applications of bio-based materials for managing acoustic comfort
Several architectural projects have demonstrated the effectiveness of bio-based materials in terms of acoustics. For example, the use of hemp panels in concert halls has significantly reduced reverberation, thereby improving perceived sound quality. Similarly, schools have incorporated plant fiber insulation to reduce noise in classrooms and cafeterias, creating an environment more conducive to learning.
Recommendations for building professionals
When designing or renovating buildings, it is crucial to consider the acoustic properties of the materials chosen. Bio-based materials offer an environmentally friendly and high-performance alternative to traditional insulation materials. However, it is essential to ensure that they are suitable for the specific requirements of each project. It is recommended that building acoustics experts be consulted in order to optimize the solutions implemented.
Integrating bio-based materials into the management of acoustic comfort in buildings is both an environmentally friendly and effective approach. These materials help to create healthier, more comfortable, and more environmentally friendly living and working spaces. By adopting these solutions, building professionals are responding to acoustic challenges while supporting sustainable construction practices.
Sources:
"The fundamentals of building acoustics and the advantages of bio-based materials"(Batylab & Ouest Acoustique – 2025)
"Bio-based materials for building acoustics"(Acoucibe – 2020)
"Acoustic properties of bio-based materials"(Cerema – 2018)
