It’s never quiet in the office because it is filled with things that constantly emit noise. Starting with technical devices such as computers, printers, and the coffee machine, through ringing telephones and keyboard noises, to colleagues talking to each other.
Poor ability to focus, reduced performance, as well as a high stress level are just some of the various negative consequences that can be traced back to a too high noise level in the office. By optimizing the room acoustics, you can do a lot against noise and poor speech intelligibility in the office and create a more pleasant, quieter working atmosphere. Find out why improving room acoustics is important and how you can achieve it in this article.
The problem of poor acoustics in the office
The high noise level in the office is absorbed and processed by our hearing without being filtered – whether we like it or not. Especially offices with modern construction, such as in loft and industrial design, have to contend with an extremely high basic noise level. Due to minimalistic interior design and large, bare surfaces, sound spreads through reflections in all areas of the room. But also in all other office spaces or in the home office, acoustically untreated rooms quickly reach too high a noise level.
According to the German industrial standard (DIN), a maximum noise level of 45 dB is recommended for office activities that require a higher level of concentration. An office printer generates a noise level of up to 50 dB, and a conversation between two people can reach up to 60 dB in an acoustically untreated room.
This is where the so-called Lombard effect comes into play: It says that in the case of loud noise sources, people automatically speak louder. If several colleagues are talking at the same time, they unconsciously raise each other’s volume. Important here: The Lombard effect also works in reverse. If background noise is minimized by optimizing the room acoustics, employees automatically speak more quietly and the volume in the office decreases.
Reflexions
The reason why sound waves in the office spread rapidly to all areas, building up to a high noise level, is reflections. Hard surfaces such as glass, concrete, parquet and tiles reflect almost 100 percent of the energy, which means that these reflections mix with direct sound (for example, voice). The combination of direct sound, reverberation and reflections results in a higher volume level in the office.
Reverberation time
One of the most important indicators of optimal room acoustics is the reverberation time. This specifies how long a sound is audible in the room after it has been turned off. You can get a first impression by clapping your hands loudly, for example. If the reverberation is clearly audible, the reverberation time is probably over one second.
The optimum reverberation time depends on the size and type of use of the room. According to the German Federation of Institutions for Statutory Accident Insurance and Prevention (DGUV), the reverberation time in an unoccupied office should not exceed the following values:
| Call center | 0.5 seconds |
| Multi-person and open-plan office | 0.6 seconds |
| One- and two-person office | 0.8 seconds |
However, most acoustically untreated offices are well above one second.
Speech intelligibility
Have you ever noticed that you have to speak loudly in the office and yet your conversation partner has difficulty understanding you? Frequent enquiries and stressful conversations are the result. These unpleasant situations result from poor speech intelligibility due to the room.
This is directly related to the reverberation time as well as the reflections in the room and indicates how intelligibly speech is transmitted. The reverberation and reflections mix with the direct signal of the voice, which has a negative influence on speech intelligibility. If you increase the sound absorption in the room, speech intelligibility is improved. The result is that you can speak more quietly and still be understood without any problems.
The consequences of high noise levels in the office
The direct consequences of constant exposure to noise and poor intelligibility are immediately noticeable: concentration problems and an associated higher error rate, as well as a reduced performance. In the medium term, too much noise in the office impairs the well-being of employees, the stress factor increases and performance decreases permanently. As a result, psychological problems can manifest themselves in the long term, leading to absenteeism and health problems in old age. This was also the conclusion of a recent study by the Cardiology Centre of the University of Mainz. It confirms that noise pollution not only affects cognitive performance, but can also promote stress, sleep disorders, cardiovascular diseases and strokes.
Measures to improve room acoustics in the office
Sound absorption
To reduce reflections and reverberation time in the office, absorptive materials must be installed in the room. In office buildings, for example, mobile partition walls or wall and ceiling sails are ideal for this purpose, which can be easily mounted on the walls and ceiling with the appropriate brackets. Acoustically effective pictures are available for individual motifs, adapted to your corporate identity. Acoustic curtains, placed in front of windows, provide large-area absorption and can effectively eliminate disturbing reflections.
The placement of the acoustic elements in particular has a decisive influence on the acoustic result. A clever arrangement can, for example, separate office islands acoustically from each other without running the risk that employees within an island can no longer communicate well with each other. All these factors are taken into account by experienced acousticians during a room acoustic consultation.
Sound insulation
Especially in an open-plan office, it can make sense to separate areas acoustically from each other. This way, sound does not have the opportunity to spread throughout the entire office in the first place. In addition, quiet areas or rooms for meetings can be created. In this case, we speak of sound insulation or sound shielding. This does not require any costly conversion measures; on the contrary, it can be easily implemented with the help of soundproof curtains or mobile walls. Particularly in the case of acoustic curtains, it is important to ensure that they are manufactured in several layers, using both heavy fabric and dense insulating foils.
The great advantage of acoustic curtains is that they combine sound absorption and sound insulation. Therefore, from an acoustic point of view, they are often preferable to structural measures such as the installation of walls or glass panes.
By the way: Room acoustic optimisation does not have to be expensive. Often, just a few well-placed elements are enough to achieve a noticeable acoustic improvement. And even for large rooms, there are inexpensive solutions with excellent acoustic properties.
Better office acoustics with HOFA
Are you interested in our products and would like to have your office acoustically optimised? Our experienced acousticians will be happy to provide you with a free consultation! With our products, we can then design your working environment acoustically ideal. We also offer various services such as professional room acoustics measurements, 3D room planning and installation services. You can reach us by email at akustik@hofa.de or by phone at +49 7251 3472-400.
Below you will find an overview of our modules and curtains that are suitable for optimising office acoustics:
- HOFA Wall and Ceiling Sail
The plain HOFA Wall and Ceiling Sails ensure more quiet and better speech intelligibility in the office thanks to high absorption in the speech range. - HOFA Mobile Wall
With the help of the HOFA Mobile Wall, workplaces can be separated acoustically. The module is mobile and can therefore be used flexibly. - HOFA Desk Divider
The HOFA Desk Divider is also used for acoustic separation of workplaces. The module can be fixed to the desk using clamps to save space. - HOFA Acoustic Picture
Design your office just the way you like it. The HOFA Acoustic Picture can be printed individually according to your wishes. - Acoustic Curtain STUDIO
Due to the high absorption coefficient of the HOFA Acoustic Curtain STUDIO, the reverberation time is reduced and reflections are attenuated. - Acoustic Curtain ISO
The HOFA Acoustic Curtain ISO combines absorption and sound insulation and is therefore ideal as a room divider in the office.
