What is a noise barrier? How does a noise barrier work? What options are available?

If there is noise pollution, there are various methods for reducing it. Broadly speaking, they can be divided into three categories:

• Measures at the source (quiet asphalt)
• Measures to Be Taken by the Recipient
• Measures in the transfer

A noise barrier falls into the last category.

 “That noise is driving me crazy!”

A noise barrier is nothing more or less than a barrier between a noise source (A) and a receiver (B). The noise barrier prevents sound waves from traveling directly from A to B. As a result, the sound must travel a longer distance, which reduces its volume. If you make the detour long enough, the noise pollution will decrease.

A noise barrier must be heavy enough to prevent resonance. Resonance essentially means that the barrier moves in sync with the sound wave, which is then amplified and transmitted through the barrier. The mass and stiffness of the noise barrier are therefore important.

The core of the screen must not be porous, because air also carries sound waves through it. Due to its open structure, Styrofoam filling has virtually no sound-insulating effect.

Finally, a good noise barrier has a large, porous surface that absorbs sound. This prevents the sound from being reflected. Noise barriers made of concrete, glass, or wood have no sound-absorbing properties due to their hard surfaces and will reflect the sound. A Greenwall® green noise barrier has a surface made of coconut fiber fabric that is covered with plants. This combination results in an extremely high absorption value. It does not reflect sound but absorbs it, thereby preventing noise pollution elsewhere.

Earthen Wall

Earthen embankments, known as noise barriers, are often used to serve as noise screens. They have sufficient mass and are inexpensive to build. In addition, they can be vegetated, which adds to their scenic value.

The disadvantage of an earthen barrier is the gentle slope of the embankment. On the one hand, this means that a 5-meter-high noise barrier would quickly have to be 10 meters wide. On the other hand, a sound wave will “roll” over an earthen barrier relatively easily and still hit the ground further down the line.

Noise barriers are widely used in public spaces, often to reduce traffic noise or noise pollution from railways. Increasingly, noise barriers are being used in private homes to create peace and privacy in the garden.