Soundproofing vs Sound Absorption

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To assist customers who are not sure whether they need soundproofing materials or sound absorbing materials, the short definitions below will help provide a brief outline. If you want to soundproof a room as fully as possible, you will almost always need to install both types of sound insulating materials.

Soundproofing

Soundproofing is all about creating an acoustic barrier. Soundproofing products are specially designed and manufactured to perform as an acoustic barrier by reducing the amount of sound entering or leaving a room.

Sound Absorbers

Sound absorbers are designed to absorb the sound within a room and help to reduce the amount of reverberation or echo within the space.
If you want to soundproof a room as fully as possible, you will almost always need to install both types of sound insulating materials.

What types of sound are there?

There are two fundamental ways in which sound moves around the rooms and spaces in which you hear them:

• Airborne Sound
• Impact Sound

What is airborne sound & how to insulate against it?

Airborne sound is sound waves moving around within a space, such as a room. This sound bounces off walls and floors causing vibrations within those surfaces which will then transmit (re-radiate) to the other sides of the room (receiver space). Often the windows, doors, poorly fitted sockets or any cracks in a wall will drastically reduce its insulation of airborne sound. To reduce the amount or loudness of this sound you need to insulate it with the use of proper soundproofing materials on your walls, floors or ceilings.

What is impact sound & how to reduce it?

Impact sound starts with an incident like a door slamming or heavy footsteps which then creates vibrations directly through the walls and floors of a building, and the sound travels from one room to another. Impact sound can travel through a concrete floor; from one room to another even if the wall in between is a good airborne sound insulator. To reduce the amount or loudness of this sound you need to stop it at its source with proper soundproofing materials on your walls, floors or ceilings.

Nuisance noise within a room and how to reduce it

As well as unwanted noise coming from a separate room, noise from within one large room can also be a nuisance. Large open rooms can often become prone to echoes of noise incidents like people speaking loudly. In an open plan office or any kind of performance hall, this can be a real problem for individuals working or concentrating. Rooms that are prone to echoes (or sound reverberation) are typically large and have wall surfaces that absorb very little of the sound, therefore bouncing it back across a room. To reduce the amount or loudness of this sound you need to absorb it with proper soundproofing materials on your floors or ceilings.

How to Control Noise

Before considering soundproofing a building it is worth considering the quality and methods of construction of the building.
There are two main ways to reduce and control noise.

• Increasing Mass – the more mass (weight and density) a floor or wall has the less sound will make it vibrate. As a general rule of thumb doubling the mass will give a 5 decibel reduction in the sound transmitted.
• Additional Layers – adding several layers to the construction of a wall or floor can greatly improve the control of noise. Each layer will be made of soundproofing materials, slightly separated to reduce airborne and impact noise transfer.