Hemp is not just an environmentally friendly building material. Hemp fibers are also ideal for soundproofing. Sound can be transmitted between rooms and floors in different ways:
Impact sound: sound propagation through a structure (concrete, masonry, etc.).
Airborne sound: propagation through partitions to adjacent rooms.
Joints and Seams: Hemp fibers can acoustically seal joints.
Whereas in the case of partitions, adequate attention is not paid to thermal insulation, the main focus is on the sound insulation function. In lightweight walls, cavity insulation is just as important as choosing the right building materials. Hemp insulation wool meets all the requirements for cavity insulation – and is very satisfying. Sound can be effectively muted with suitable panels.
Hemp insulation can be useful in many areas:
Under floor coverings.
On the roof.
In the room.
In a recording studio.
Good results are obtained even with very small insulation thicknesses, for example 3.5 cm.
Hemp clay backfill has proven effective in isolating impact noise in floor ceilings so that sound cannot propagate throughout the building. Another possibility is sound absorption in isolated cavities.
In concrete terms, this means that impact sound is insulated in suspended ceilings so that the floor does not have direct contact with the supporting structure through impact sound insulation. Airborne sound insulation is used in cavities in a wall or ceiling.
Hemp fleece with an additional layer of light clay filler is suitable as acoustic mats between floors.
Soundproofing with hemp.
A sound wave consists of vibrating particles. If these particles hit a surface, the angle of incidence determines which part is reflected. How large or small this angle is depends on the speed of sound in the respective materials.
By air it is 343 m / s, by wood – 3400 m / s, by concrete – 3100 m / s, by steel – 5000 m / s. If sound hits water, wood, or concrete at a slight angle in the air, all the sound is reflected and nothing penetrates the water, wood or concrete. They talk about complete meditation.
Hemp fibers are so-called resonance absorbers. This means that the fine fibers of the fibers are driven by sound and the resulting vibration energy is converted into heat. The coarser fibers of hemp do not vibrate and act in the same way as mineral wool. It only absorbs sound. They talk about a porous absorbent.
Soundproofing hemp clay is made up of hemp bonfires, hemp fibers and clay. Sound in air is absorbed by the combination of a resonant absorber and a porous absorber. Flow resistance and insulation thickness are critical.