Sound envelope of a building
The first step in the acoustic study of a building is to know its sound environment. This can already be estimated, by consulting the Noise Map of the urban area (if any) or determined on a case-by-case basis, by collecting data on site.
Then we move on to the acoustic design of the building, which is nothing more than a verification of the existing designs (architecture and stability) in relation to the acoustic conditioning foreseen in the national legislation for the different types of use. If it turns out that the solutions adopted in architectural and engineering design are not sufficient to guarantee the legal insulation and reverberation conditions, the acoustic designer proposes new solutions, which must be adopted by the architect.
The main precautions to be taken in the sound insulation of a building are on the façade, on the boundary walls of the apartments and on the floors, if these separate autonomous fractions. Sound isolation is not only done for air conduction sounds, but also for percussion (or impact) sounds. Special attention is also given to noise caused by collective equipment in buildings, such as elevators, garage doors, water pumping and/or sewage systems.
In spaces with public use (cafes, restaurants, hospitals, passenger terminals, etc.) special care must be taken with reverberation, as this "increases" the noise inside these spaces.
The solution is to apply, on the interior surfaces of these spaces, materials that absorb sound, maintaining the aesthetic function chosen by the architect.
Measurements and tests
During the construction phase, it is necessary to monitor the execution work to verify the fulfillment of the project, as well as the insulation values foreseen in it. To this end, several tests and measurements must be carried out by duly accredited companies. Failure to verify the legally established values could lead to great losses (in financial compensation) for real estate developers and contractors.