Soundproofing often involves erecting walls and dampeners, but if you'd like a more natural method, as well as a more environmentally friendly one, consider trees. While not all trees will make effective sound barriers, many can provide at least some sound-dampening effects. As an added benefit, they also add beauty to a property and even provide protection from wind.
Typically, the decibel level desired around a home is 55 to 60 during the day and 50 to 57 during the evening hours. A decibel meter can help determine the ambient sound around your home. Determining how much sound you need to reduce will help determine how many trees you need and what the depth of the tree line will need to be.
One of the most important factors in using trees as soundproofing is the depth of the tree line. To get the most effective noise reduction, the tree belt needs to be 65 to 100 feet wide. The trees should be planted as close to the source of the noise as possible, as this will lead to blocking the sound waves before they become more spread out.
Trees come in many different species, but most any species can be used in soundproofing. If you need soundproofing throughout the entire year, then evergreens are often the tree of choice because they never drop their foliage. Broad-leafed evergreens may help even more than conifers, because the foliage is wider and covers more area than the needles of conifers.
In addition to the trees, it is also best to have a softer ground covering helping to make up the tree belt. Though it may be possible, especially in urban settings, to plant trees next to hard-surface areas such as concrete walks and roads, this is not ideal. A barrier of 65 to 100 feet, along with a soft surface, has the ability to reduce noise pollution by as much as half.
Though there may be considerable benefits to choosing trees as soundproofing, the disadvantages may discourage some people. The cost is one of the largest inhibitors. While it may be possible to reduce the cost by planting younger trees, it can take years for the trees to mature before an effective sound barrier is created. Further, the trees could provide a home or hiding place for nuisance animals. Also, because trees must be planted in such wide belts in order to reduce noise, such a strategy may not be practical in many situations.