This is definitely one of the most frequently asked questions. We usually answer that question with a counter-question: How much does a car cost?

Buying a Greenwall sound barrier is quite different from buying a fence—including from a financial standpoint. In the chart below, we’ve listed the costs of various types of property boundaries.

If you’d like to install a sound barrier yourself, you can purchase a Greenwall Cassette starting at €135 per m². If you’d like us to handle the installation—including setting up any posts, planting the Greenwall, and ensuring everything is neatly prepared and finished—expect a price per square meter starting at approximately €300. A significant but worthwhile investment in your enjoyment of your home!”

Absolutely! All Greenwall products have been laboratory-tested for their sound-absorbing properties and can therefore rightly be called sound barriers.

It is important, however, to position the screen in the right spot and make sure it’s tall and long enough. Sound travels along and around the screen, and you need to make that path as long as possible to get the best results.

Sound can also be reflected off nearby buildings, causing it to end up in your yard after taking a detour.

That’s a very valid question, and at the same time, it’s very difficult to answer simply. It’s related to the previous question, but it also has to do with other factors.

The noise source:Is it traffic, a swimming pool pump, or a schoolyard? What pitch do you hear? Are these bursts of noise, or is it continuous noise?

The surroundings:Are there many buildings nearby? Is there a plaza or a pond? These are all elements that can carry sound further or cause it to echo.

You:Where are you experiencing the nuisance? Are you sitting against a wall, or under a canopy? Are you the only one bothered by it, or are there others?

The best way to determine the impact of a noise barrier in advance is to conduct a GE (Noise Impact) study. You can read all about it in Question 9.

A noise barrier should make the path that sound travels from the source to the receiver as long as possible.

An infinitely long and tall screen would give the best results, but that's not realistic. There are, however, a few rules of thumb you can use:

A noise barrier must be at least 1 meter higher than the straight line between the source and the receiver.

If, while sitting on the patio (ear height 1.2 m), you’re bothered by roaring engines behind your house (source height 60 cm), then the minimum required height is 1.6 m if you place the screen next to the road, or 2.2 m right next to you on the patio.

Sound from a sound source affects you over an angle of 127º

If the noise source is at a single point—such as a heat pump—you should measure the 127º angle from the source. In the case of noise from a road, you should measure this angle from the location where you are affected by the noise.

The image above clearly illustrates exactly what that means.

Without getting too technical:sound insulationrefers to the extent to which sound does not penetrate the Greenwall.The thickness and weight of the screen, in particular, play an important role in this. You can think of it as somewhat similar to thermal insulation.

Sound absorptionis the degree to which sound is absorbed rather than reflected. Compare the sound in a bare room (without carpet, curtains, wall coverings, or furniture—hollow and echoing) to that in a furnished room. A high absorption value may be even more important than a high insulation value, because reflected sound can still cause disturbances elsewhere or via an indirect path.

That's a tough question! Actually, you should ask yourself the following questions first:

• Is there a noise disturbance?
• Who or what is causing this nuisance?
• Is that allowed?
• Who benefits from a noise barrier?

As a general rule, noise pollution caused by traffic must be kept within acceptable limits by the road authority (e.g., the municipality, province, or national government). The road authority applies standards established by law. If the road does not meet the standard, the road authority is required to take measures at its own expense. Seethis video for more information.

Not all forms of noise pollution are regulated by law. Noise pollution from neighbors, for example, isn’t covered by the law (just ask the TV show *De Rijdende Rechter*…). In that case, there are two options: you can agree to split the cost of the noise barrier and install it on the property line, or you can buy the barrier yourself and put it in your own yard.

You can also work with your neighbors to purchase a noise barrier to mitigate the noise from the road that runs behind your homes, residential neighborhood, or recreational park.

Companies often need a permit if they consistently generate a lot of noise, and must therefore take measures if they exceed the standards.

In all cases, the following applies: talk it out with each other and work together to find a solution.

A Noise Impact Assessment (NIA) or acoustic study is a way to determine in advance how effective a noise barrier will be for you, taking various factors into account.

These include the dimensions of the screen, the sound source, the location where the noise is experienced, and the surrounding environment. The study predicts how much noise reduction we expect to achieve compared to current levels. The study is conducted at a desk using acoustic simulation software. By varying the length and height of the screen in the software, it is also possible to optimize the results and, for example, achieve better outcomes.

The result of the study is a number that predicts the amount of dB reduction. Using audio clips, we can then demonstrate what that number means in practice.

A basic acoustic assessment costs €950. The great thing about it is that you don’t make the decision to purchase a sound barrier until after the assessment, so you’re protected against making a bad purchase.

Absolutely! The Greenwall is designed for both the residential and commercial markets.

For the business market, there is even a tax benefit due to the environmentally friendly investment. See also the next question.

As far as we know, there isn't one. There may be local initiatives that encourage the purchase of environmentally friendly, sustainable, or green products or services that you can take advantage of.

For business clients, there is the MIA/VAMIL program. This tax incentive program is designed for companies that invest in sustainable and environmentally friendly measures. Greenwall is listed as one such measure on the Ministry of Economic Affairs’ 2019 Environmental List. We recommend that you contact your accountant for more information.

Actually, all of the questions above apply to you as well, except… You don’t want to invest in research until the sale is certain, and you don’t want to buy if you’re not sure the problem will be solved…

The solution: have the seller conduct the investigation. This has the following advantages:

• This can demonstrate that the noise level will actually decrease with a noise barrier;
• This can be used as a reference for any potential buyer who has concerns about this;
• It increases the value of the home;
• We have a separate information page for real estate agents:What can a real estate agent do if there are questions about noise pollution?

We hope the answers above have provided more clarity on the benefits of a Greenwall. If your question isn't listed here, please feel free to send us anemail.