Room Acoustic Design

Alphacrete Acoustic Masonry

Acoustics in classrooms
Two important characteristics of an acoustically optimized classroom are a low background noise level and a low reverberation time. The background noise may be from adjacent classrooms or activity outside. Reverberation is the multiple reflections of sounds within a room that can prolong and distort the original sound components. Speech intelligibility is compromised when a soft vocal element is masked by the reflected sound of a preceding louder element. Reverberation also has the effect of amplifying background noises.

For optimum speech intelligibility a reverberation time of less than 0.6 or 0.8 seconds is required for classrooms.

Other applications for Alphacrete Acoustic
In addition to classrooms, poor Acoustics can have a significant impact on other rooms, and buildings depending on their applications.

Assembly halls.
The number of hard surfaces in a hall makes it an extremely ‘live’ environment as far as sound is concerned. As a result speech intelligibility often suffers in this environment. Assembly halls within schools in particular due to the variety of applications are often an acoustic challenge. Typical uses can range from drama, parents evenings, lectures, exam halls, sports use, audio / visual presentations. A room where a whisper can be heard as well as a school choir can prove challenging.

For optimum speech intelligibility a reverberation time of 0.8 to 1.2 seconds is required for assembly halls.

Sports halls.
Typically gymnasia sports halls are built to be robust. Sports halls require large volumes of space with excellent light and acoustics. in order for the users to enjoy their activities without distraction. The design of sports halls normally incorporates a number of hard surfaces to withstand use, unfortunately these combine to produce particularly poor acoustics.

Reverberation time of less than 1.5 seconds is required for sports halls.

Music Rooms

Music rooms are one of the most challenging when it comes to acoustics, as music will produce more sound than any other type of lesson in a school. The design of the room itself should be considered, and parallel walls should be avoided if possible to reduce the occurrence of flutter echoes and standing waves.

Reverberation time of less than 1.0 seconds is required for music classrooms and less than 0.8 seconds for small practice / group rooms.

Conclusion
Alphacrete Acoustic effectively deals with room acoustic problems, by the absorption of the reverberant sounds. It achieves this through its unique geometry and mix design, and has been tested and accredited by sound research laboratories. All measurements of sound transmission were performed in accordance with the guidance set down in BS EN ISO 140: 1995: Acoustics – Measurement of sound insulation in buildings and of building  elements, Part 3 – Laboratory measurement of airborne sound insulation of building elements. Alphacrete Acoustic offers excellent resistance to the transmission of airborne sound, and with a wide range of colours available enables specifiers to create stunning schemes which not only look good, but sound good too.

You can view further product data on Alphacrete Acoustic on this website.