Cooling a room with a chilled ceiling combined with Ecophon Solo. The red and blue arrows represent natural convection and the curled arrows represent radiation.
Thermal comfort
Thermal performance is increasingly taken into consideration in the programming and design of office buildings. Many of these offices are using the thermal capacity of the structure mass to provide thermal comfort - they are using thermally activated building systems (TABS), also known as concrete core activation (CCA). This technique provides stable thermal conditions and is expected to be energy efficient in the long term. The thermal issues require much of the structure (typically concrete) to remain exposed to the room environment.
Acoustics
The use of free-hanging units provides flexibility and a multitude of acoustical solutions to acoustical design. Free-hanging units can be an efficient way to add absorption to a room.
In premises where, for various reasons, an overall ceiling cannot be used, e.g. where temperature is regulated via concrete slabs or where there are large areas of glass, absorbent islands offer an efficient way of creating a good acoustic environment. Absorbent islands can be designed as horizontally suspended units or for use as baffles.
Nevertheless, acoustically a complete wall-to-wall ceiling is generally a better solution than free-hanging units. This is especially emphasized at low frequencies.
Knowledge Guides
Our experience in this field dates back to the beginning of 2000 following frequent use of these techniques in continental Europe. This experience and the result of various tests we have conducted are summarized in our Knowledge Guides on acoustics and thermally activated building systems respectively. (See the right hand column for pdf download)
There is no real conflict between acoustics and thermal performance in buildings using free-hanging units. A coverage of 60% with sufficient distance between panels and appropriate mounting depth will secure both acoustic performance and thermal efficiency. Some general statements are summarized in the table below.
|
Covering with acoustic ceiling |
No ceiling(exposed structure) |
30% covering |
60% covering |
100% wall to wall ceiling |
|
Acoustic performance |
N/A |
Weak acoustic solution. Requires acoustic wall panels. |
Works in most cases. Acoustic wall panels are a useful complement. |
Optimal |
|
Thermal efficiency |
Optimal |
Works in most cases |
Limited influence on thermal efficiency |
N/A |
|
Ecophon statement |
N/A |
Unsecure. Too little absorption |
Optimal. Works well, acoustic wall panels are recommended. |
N/A |
N/A: Not Applicable