Building Acoustics: The Basics

Whether you're buying a home, looking for a space for your business or just making some renovations to an existing structure, you've probably heard a lot about building acoustics. But what does it actually mean, and why should you be concerned about it? 

The science of sound

When something makes a noise, it agitates the air around it; the sound travels as a vibration through the air until it reaches our ears. Because the sound is a wave in the air, it can bounce off other objects or be absorbed by them. How the sound is reflected or absorbed depends on the shape and composition of the surface the wave strikes. The properties of all the surfaces in an area combine to form its acoustics. 

Why it matters

The acoustic properties of a space can make a huge difference to what it can be used for. For instance, a lecture theatre is designed so that a person speaking at the front can be heard clearly at the back. By contrast, office buildings try to make it harder for sound to travel long distances so that people can work in peace even if their colleagues are speaking nearby. Good acoustic design can also help keep a building quiet even when there are nearby noise sources such as train tracks or busy streets.

A building with the right acoustics can make a huge difference to customer or employee experience, often in a way that isn't immediately obvious. Restaurants, for instance, put a lot of attention into creating acoustics that make conversation from others at a table easy to hear while keeping the overall noise level of the dining area to a minimum. Studies have shown that a certain level of background noise is actually desirable; humans find long periods of absolute silence distressing. The goal is to achieve exactly the right amount of noise without being too loud or distracting. 

Elements of architectural acoustics

Several components go into the acoustics of a building: the layout of the space, the materials used in the building and any other objects, such as plants or furniture, that might be in the space. For instance, recording studios use soft, padded surfaces that absorb rather than reflect sound to cut down on echoes, while architects choose heavy materials and small windows to minimise vibration and keep sound transmission down. The hollow spaces between floors in a block of flats act to amplify sound, which explains why upstairs neighbours always sound as if they're about to crash through into the flat below. When designing a new building, acoustics experts can help avoid these kinds of unintended consequences. 

Building acoustics and you

When thinking about buying or renting a new building, it's worth testing out the acoustics to see whether they work well for the purpose you intend to use them for. Will employees be able to hear one another? Will noise from one bedroom disturb people sleeping in another? Remember that furniture can change a room's acoustics as well, so consider this when making your decision.