Within a city, various factors are taken into account when it comes to housing, such as location, proximity to services, mobility, access to natural light, view, and noise levels. These considerations are particularly crucial in densely populated areas, with a stronger relevance to apartments in high-rise buildings. In contrast, when designing a house, specific factors are inherently addressed. It is assumed that a single-family residence is situated away from busy city centers, leading to longer commutes for services. The availability of natural light is influenced by the location of the building on the land, and noise is minimized because residential areas are usually away from bustling urban environments.
Nevertheless, these assumptions may depend on the specific context of the city. When it comes to noise, prevention efforts typically focus on blocking external sounds from entering the building. However, dissipating sound from inside to outside is also a significant concern. In vertical buildings, the influence of sound between apartments can be seen as an advantage or disadvantage for residents. In a house, this issue is also raised, though less frequently. However, it should not be forgotten that heavily equipped TV rooms or certain lifestyles can disturb neighboring houses or even residents within the same household.
There are subtle nuances in sound propagation that can be mitigated in certain contexts; therefore, it is crucial to differentiate materials and their properties concerning sound to achieve the expected performance. When it comes to sound insulation (preventing the spread of sound), it involves volume, mass, and density. However, beyond just preventing sound propagation, an ideal environment requires sound absorption to prevent disruptive reverberation during activities. This involves less density and volume. For excellent and controlled acoustic performance, architectural design should be complemented by a well-executed acoustic engineering plan. In other cases, it is beneficial for architectural professionals to have some technical understanding of how to achieve the desired acoustic outcomes in spaces.
Residential renovations or constructions may not necessitate the intricate acoustic control required in a performance venue. However, this does not imply that they do not need any acoustic attention. To improve sound comfort in homes—whether they are standalone, located in urban settings, or within individual rooms—there are essential design strategies to be implemented. Before choosing isolating or absorbing materials, it is crucial to determine the desired sound effect, whether it be reducing noise or enhancing sound propagation. Depending on the project's concept, sound propagation might be intentionally desired. For instance, in the Butantã house by Paulo Mendes da Rocha and João de Gennaro, walls intentionally do not touch the ceiling, aiming for the sound from common areas to infiltrate private spaces and vice versa. In more conventional settings, specific choices of application and materials can improve acoustic comfort in residences.
Wood
Wood is predominantly used, also for acoustic purposes. After all, it is aesthetically pleasing and readily available in the construction market. When employed as a ceiling, flooring, or wall covering, wood helps absorb a portion of sound waves while enhancing the visual appeal of the space. Slatted or indented panels can further reduce sound reflection compared to a smooth surface of the same material. If wood is not directly affixed to the underlying surface, you can utilize the space between them to introduce a layer of rock wool or other insulating material. This enhances the acoustic performance of the environment.
Single-family House in Bonlez / LRARCHITECTES
House for Cellist / Unagru Architecture Urbanism
Rusty House / OK PLAN ARCHITECTS
Terrace House near Demachiyanagi / atelier Luke
Cork
Derived from wood, cork is obtained from the bark of the cork oak tree (Quercus suber). As a result, it shares its thermo-acoustic properties and can be used as a covering or filler. Due to its organic nature, cork presents itself as an environmentally friendly option. However, harvesting raw material for cork production involves trees aged between 25 and 30 years, a timeline that contradicts the typically fast-paced requirements associated with construction. Nonetheless, cork used in construction can also be sourced from recycling processes or the waste generated during its production.
Chestnut House / João Mendes Ribeiro
House in Praia Grande / Atelier Data
The House of Wood, Straw and Cork / LCA Architetti / luca compri architetti
Thick or Composite Walls
A significant aspect of sound isolation relies on robust enclosures capable of preventing the "leakage" of sound. Walls with significant mass and thickness, along with high thermal inertia, effectively prevent the transmission of noise from one space or building to another. Whether between rooms or between a residence and its surroundings, dense or composite enclosures—referred to as sandwich structures, involving a combination of two external layers with a core made of thermal, acoustic, or dual-insulating material—block the escape of noise. However, isolation alone does not guarantee sound quality within the space where the sound is produced. Therefore, in addition to effective enclosures, it is ideal to have appropriate sound treatment within the specific environment.
4x4 Studio / Teresa Mascaro
Country House / zaa
gjG House / BLAF Architecten
Composite Roofing
Similarly to vertical enclosures, roofing can be lined, treated, or combined to improve acoustic performance in space. Sandwich roof tiles are convenient for installation due to their standardized nature. However, achieving a similar effect is also possible by combining different materials. Once again, wood can be employed, or insulating materials can be placed between the ceiling and the slab. The option to combine materials makes sense in processes that allow for self-construction, as seen in the case of the Domotej roofing used in the Manancial house.
Casa Mantiqueira / ARKITITO Arquitetura
New Moon House / Vivian Hunnicutt arquitetas e associadas
Manantial House / Apaloosa Estudio de Arquitectura y Diseño
The fundamental principles for enhancing the acoustic performance of a project are diverse and can be combined and explored—spanning materials, techniques, and the construction's shape. The fundamental understanding of sound interaction with any surface marks the beginning of a successful acoustic design. Its development will align with the program and context demands, whether aiming for silence or amplification.
