There is a balance in creating spaces that look good but also feel good to be in.
We are often absorbed by the aesthetics of a space, but what if other elements, such as noise, make a space unsuitable for the intended purpose? What if being in the space is an unpleasant experience?
In certain places, such as offices and learning facilities, sound management is especially important. Productivity and inclusivity can be affected by a noisy space.
In restaurants and community spaces, acoustics ensure that the patron’s experience is pleasant. This can be a critical factor in the success of the business – would you return to a restaurant if you couldn’t hear what the person next to you was saying?
How do acoustic panels work?
Acoustic panels are used to improve the experience of a room by absorbing sound waves and reducing reverberation.
Sound waves can be reflected or absorbed, and the science of acoustics is largely about what to reflect, what to transmit, and what to absorb.
Sound travels until it meets resistance (for example a wall), at which point it reflects off. Acoustic panels work by absorbing this sound, subsequently making a space quieter to be in.
Acoustic panels vary in material and design and each of these elements works differently to manage the absorption (or reflection) of sound.
At Decor Systems, we have an extensive range of acoustic panels to suit the needs of any space – both from a sound management as well as aesthetics point of view.
Key acoustic terminology
There are some key terms to understand when specifying acoustic panels. We go into detail about these in our CPD presentations, which you can book through one of our project consultants.
Noise Reduction Coefficient (NRC)
Noise Reduction Coefficient is an average rating of how much sound an acoustic product can absorb.
It is a simple number index range from 0 to 100, which represents the percentage of sound that is not reflected off the material (in most cases, the structural materials and surface finishes) and instead, circulates back into the room.
A high NRC rating indicates that the material of choice is absorbing the sound, which ‘deadens’ the sound in the room.
A low NRC rating indicates that the material is not absorbing sound, and is generally found in hard reflective surfaces, i.e., tiles and glass.
Decibel
Another key term that you will come across when specifying acoustics for a space is ‘Decibel’.
Decibel or dB deals with the loudness of sound. The decibel (dB) is a logarithmic unit – an increase of 3dB is twice the sound pressure or loudness.
Example: A 90dB sound event is equal to a power ratio of 1 billion. An increase of 30dB means the power ratio increases to 1 trillion!
Adding sound absorbing materials into a room will reduce the dB or the loudness of sound.
What are acoustic panels made from?
Acoustic panels are made from a variety of different materials including timber, fibre cement, plasterboard, and wood wool.
Each comes with a different acoustic rating and is suitable for a variety of applications. Acoustics need to be managed differently in different spaces, for instance, in a library compared to a music room.
Most acoustic panels are made from a combination of timber with a sound-absorbing backing material that is made from an absorptive material.
Acoustics versus aesthetics
At Decor Systems, we try to strike a balance between acoustic panels that not only manage sound but are also aesthetically pleasing. So, once you select the rating and provide our project consultants with a brief on what you’re trying to achieve, the Decor team can work with you to create a solution that blends in with the aesthetics of the space you are designing.
When it comes to specifying acoustics, there are many factors to consider. Decor Systems should be viewed as an extension of your team so we can work together to ensure that you achieve exactly what it is you’re after.
Top tips for specifying acoustics:
- Understand the acoustical properties of the materials you are considering, such as sound absorption and transmission.
- Determine the required noise level reductions for the space and select materials that will meet those requirements.
- Consider the environmental impact of the materials and choose options that are sustainable and have low emissions.
- Take into account the aesthetic design of the space and choose materials that complement the overall look and feel.
- For a space with multiple functions, such as a conference room that is also used for music performances, consider using different types of materials for different areas of the room to optimise acoustics for each use.
- Work with an acoustic consultant for site measurements and recommendations for material specification.
- Careful attention should be paid to details, such as the proper installation of acoustic materials to ensure optimal performance.
- Understand the needs of the space: Is it going to be a space for collaboration and communication or for concentration or creativity?
- Be aware that sound, like water, will find the weakest point through. Therefore, voids in ceilings and ducts need to be addressed.
- Understand that sound travels through any medium, not just air. Structure-borne sound needs to be addressed separately from airborne sound.
- Good sound attenuation relies on density and air tightness.
- Consider allowing background sound into meeting rooms to provide masking and privacy for room-to-room attenuation.
- Sound absorption needs to be considered alongside sound insulation.
- Employ a competent professional acoustic consultant. Your Decor Systems consultant will be delighted to assist you with this.
7 design tips for the best architectural acoustics
- Watch out for sound reflections. Straight surfaces reflect sounds back into the central space making sound clarity muddy.
- Select acoustical treatment carefully. Different materials absorb sound frequencies differently. Make sure your acoustical treatments are absorbing the right sound frequencies.
- Diminish echoes when necessary. Be aware that sounds travelling within 30 milliseconds of each other are perceived without an echo. Sounds travelling after the 30-millisecond threshold become echoes of the original sound.
- Don’t let other building systems get in the way. Noise control is important to keep in check in other building systems (such as HVAC systems) operate. Keep such clashing noises to a minimum.
- Keep objects or other obstructions out of the way. Objects that obstruct a sound path can block high-frequency sounds. (Low-frequency sounds can bend around objects.)
- Get good pattern control. Make sure sound systems for a room get good sound coverage. This will prevent feedback and other sound distortions.
- For out-of-the-way listening areas, get distributed sound systems. Such ‘delay-fill’ speakers operate with an electronic delay, so the sound matches and is synchronised.
The importance of incorporating acoustic requirements at the design stage
Involving acousticians in the early stage of project design will ensure that you achieve optimal sound performance and avoid costly and unattractive Band-Aid solutions after project completion.
It is not always about reducing noise, but more about achieving the right acoustic outcome to make the space fit for the purpose for which it is built.
When working hand-in-hand with an acoustician, architects can achieve a sound acoustic outcome, overcoming many challenges that are commonly faced in the process.
The Surry Hills Community Centre, designed by Frances-Jones Morehen Thorp (FJMT) was intended to meet the various needs of the local community and includes an integrated local library, community centre and childcare centre. Each space within the centre has very different acoustic requirements, which was a key challenge of the project.
Decor Systems products were specified by FJMT to assist with achieving various acoustic qualities for different users within the centre. In an article by Architecture & Design, it was addressed that in this project “the inherent high-energy and high-noise of both the childcare and community centre zones require acoustic absorption to allow users to engage and interact without excessive noise carrying into the library. To achieve this, the architects used pre-finished, fire-rated, perforated acoustic panels (DecorZen and DecorStyle – by Decor Systems) extensively throughout these spaces, achieving up to 88 per cent of incidental noise absorption.”
Your acoustic checklist
It is imperative that you plan ahead and clearly scope out your requirements in view of making the right product system specifications at the conceptual stage of your project.
Retrofitting acoustic panel systems following completion can be expensive and time-consuming, will interfere with schedules, and often has a ‘Band-Aid’ look about it. Hence the need to clearly delineate and analyse potential issues beforehand in view of intelligently addressing them at the most appropriate time.
Plan ahead what you need to know:
- Room dimensions
- Ceiling height
- Type of lighting
- Ventilation/ductwork
- Fire rating requirements
- Environmental accreditations required
- Potential issues
- New build or retrofit?
- Current sound treatments
Diagnosis – What are your main sound issues?
Part one:
- Echo
- Excessive noise
- Reverberation
- Sound quality
- Speech intelligibility
- Hearing protection
If any of these is a critical issue, you will need sound absorption products.
Part two:
- Sound transfer
- Low frequencies
- Impact noise
- Vibration noise
If any of these is a critical issue, you will need sound isolation products.
Absorption treatment
It is vital that the correct level of absorption is ascertained.
- Light Absorption
- Typically, 5% – 25% coverage is required.
- Typical applications include recording studios, interview rooms, conference rooms, offices, etc.
- Moderate Absorption
- Typically, 25% – 50% coverage is required.
- Typical applications include theatres, open-plan offices, etc.
- Heavy Absorption
- Typically, 50% – 60% coverage is required
- This is for heavy applications such as vocal booths, recording isolation booths, and other areas that require almost total absorption.
Absorption materials should be installed so that they are exposed to the source of the noise problem for it to work most effectively. In most applications, they work best if they are positioned evenly around the space you are treating.
Isolation treatment
Some recommendations for sound isolation include:
- Look for areas where sounds may be escaping: Doors, windows, ductwork, and vents are the common culprits.
- Employing thicker, less compressed materials to reduce impact and/or vibrational noise.
- Thinner, denser materials work best for sound isolation.
- ‘Seal’ the room. Make every effort to cover every surface with an appropriate sound isolation material to prevent sound from escaping or entering.
Sound isolation materials need to be installed between wall layers. For new buildings, isolation materials can be attached directly to wall studs or floor joists. For retrofit applications, isolation materials may be added to existing walls followed by additional layers of plasterboard over it; the more mass, the better the outcome!
