What are the acoustic properties of wood?
For centuries, wood has been considered a material with unique acoustic performance. This is why wood is frequently used to make musical instruments and build performance spaces.
In commercial and residential construction, the acoustics of materials such as wood are an important factor to consider, because many people look for acoustic comfort when buying property.
In this article, our prefabricated wood structure specialists will tell you more about the acoustic properties of wood and why they should be taken into account in construction projects.
Acoustic comfort achieved by reducing vibration and sound transmission
In order to achieve comfortable acoustics, wooden residential and commercial buildings must be carefully designed to reduce vibration and sound transmission.
All types of buildings are subject to two types of sound that can be mitigated through the proper use of wood:
- Airborne sound (speech, sound systems)
- Impact sound (footsteps, objects falling)
In both cases, these sounds can move from room to room, annoying the occupants and making the area uncomfortable.
Two units of measurement are used to quantify the acoustic comfort of a building and evaluate its soundproofing: Sound Transmission Class (STC) for airborne sound and Impact Insulation Class (IIC) for impact sound. The National Building Code (NBC) requires an STC of at least 50 and recommends an IIC of 55, but doesn’t require it.
Wood as acoustic insulation
Because wood is a light and relatively rigid material, its soundproofing properties aren’t particularly good. Furthermore, its smooth, compact surface tends to reverberate noise rather than dampening it.
However, because of its low density, it can be an advantageous acoustic insulator in some circumstances.
Lower density = better soundproofing against airborne noise
The denser a material is, the more easily it conducts sound. When compared with materials such as steel and concrete that can be used to construct the framework of a building, wood is the one with the lowest density. That’s why wood is able to absorb vibrations and sound well.
Taking the acoustic properties of wood into account in construction projects
With the right design, property owners can enjoy as much privacy and acoustic performance in wood structures as they expect from steel and concrete buildings. It is simply a question of knowing the acoustic properties of the softwood lumber used and taking them into account in order to minimize sound from airborne sources and people moving inside the building.
For walls in timber frame structures, soundproofing can generally be done in one of two ways: using heavy partitions or using lightweight partitions separated by empty space.
Heavy partitions will absorb the vibrations transmitted into the wood frame, while empty space will simply prevent the vibrations from spreading.
Soundproofing panels can also be added to reduce the propagation of sound through the walls. More and more prefabricated wall manufacturers are offering to integrate this type of insulation into their custom products.
Soundproofing floors and ceilings
Noise control can be improved by increasing the mass of floors and ceilings with a combination of lightweight concrete, soundproofing panels, subfloor, floor joists and layers of gypsum boards.
Soft floor coverings and driftwood can further mitigate sound transmission.
UsiHome: your partner in acoustic comfort
In conclusion, the acoustic properties of wood are such that certain precautions must be taken when constructing timber frame buildings to prevent sound spreading easily from room to room.
At UsiHome, we can help you construct buildings with good acoustic insulation by adapting our structural wood products to suit your needs. Contact us and tell us about your acoustic comfort requirements!