We talk a lot about sound treatment for architecture but normally for new projects. In projects that are already built, either a rented apartment or small commercial space, we often have to deal with noises that we can't control, affecting our physical and mental health. In this article, we explore practical tips on how to manage and reduce these noises and improve the quality and atmosphere of these environments.
As shown in the 2012 film Neighboring Sounds (Portuguese: O Som ao Redor), by Kleber Mendonça Filho, the sounds of the neighborhood have a major impact on our routine. Cars, buses, motorcycles, construction sites, music, conversations, barking, and meowing, are all sounds that are part of living in big cities. However, at the same time, they can be a problem when we have no control over them or the possibility of isolating ourselves.
The conventional building materials used in the most recent constructions have limited acoustic insulation properties. Walls made of clay or concrete bricks, or even structural blocks, are not capable of isolating the sound from one apartment to another, for example, without the use of an insulating layer. Conventional windows don't normally provide great sound isolation either. The usual window frames do not have this capacity either, nor do the slabs and so on. In these cases, we need special solutions to improve the interior environments.
First of all, it is important to know that, unless the goal is to build an anechoic chamber, no solution is one hundred percent insulating, and therefore, the feasible solutions are designed to soften external noises and not to completely insulate the environments. With this in mind, the first step is to understand where the noise is coming from, is it from a neighbor, above or next door, or is it a sound that comes from the street and enters through the windows and doors? For each case, there is a different approach:
Noises coming from the street
If you determine that the noise is coming from the street and entering the room through a window, the most effective solution is to install a double-pane window, which can achieve somewhat greater sound damping than single-pane windows due to the double glazing and frames, that are also filled with a sound-reducing material. In addition, these windows also have an almost airtight seal that helps to insulate the interior environment. You can easily replace your conventional window with a double-pane window, although it will require some renovation. Or, you can install a second interior window over the regular window, which means the window will project 5 to 7 centimeters (2 to 4 inches) into the room.
Noise coming from next-door neighbors
If the noise is coming from the neighboring dwellings, which happens in most apartment buildings, an acoustic panel might be a good solution. In the past, residential projects usually had double or thicker walls to isolate the apartments from their neighbors, but as time went by, contractors started valuing cost reductions over the residents' comfort, so nowadays, the partition walls hardly ever have any type of acoustic barrier.
One way to get around this, is building an acoustic panel right next to the wall, adding an extra layer of insulation. This layer is composed of 3 fundamental elements: the insulating material, which can be either wool, PET, or mineral; the structure of the panel, which can be drywall attached to the wall or even a wooden structure; and the external finishing, that can be done in many different ways such as painting, woodwork, etc. As this solution implies building an extra layer over the existing wall, the size of the room will reduce about 5 to 10 cm (3 to 4 inches) depending on the situation, so it is important to carefully analyze this solution beforehand.
Noise coming from upstairs neighbors
As uncomfortable as it is to hear conversations from next-door neighbors, it is even more uncomfortable being disturbed by upstairs neighbors walking and dragging furniture around. One of the biggest challenges in these situations is that we can not only hear sounds, but also vibrations that travel from one floor to the other, dissipating through the slab and down the walls. So it is important to remember that it is almost impossible to achieve an environment with full isolation in a multi-story apartment or office building, however, there are solutions to reduce some of the noise. Some solutions are more radical, such as installing a rubber sheet between the floor and the slab, and others are more simple, such as installing ceiling panels. The rubber sheet is a good solution if you are remodeling your apartment and want to avoid any problems with your neighbors downstairs, but it does not work the other way around, since it would require renovation inside your neighbor's apartment. In this case, you can install ceiling panels that are detached from the upper slab. These panels work the same way as the wall panel, but they have to be hanging from the ceiling to create a cavity that can dampen the vibrations from the apartment above.
It is worth pointing out that these solutions are intended to soften external sounds and not internal reverberations. For this purpose, there are other interior solutions already explored in other articles published here at ArchDaily. The insulation of an environment involves careful detailing of all the extremities, the walls, ceilings, and floors, their materials, and finishes, and the windows need to be properly sealed. Although complete insulation is only possible in very controlled environments, these solutions can help reduce noise from the surroundings and improve the dwellers' quality of life.