2. Why acoustic matters in restaurants
● Now a days restaurants have become very loud places
with a great of reverberation and echo.
● Both traditional and quantum acoustics have solutions for
creating quieter, clearer spaces with the ability to have a
decent conversation at a reasonable volume.
● One of the major hindrances created by poor acoustics of
a restaurant or any commercial space is making the
communication difficult.
● Customers would love the soft music and hustle bustle of
the restaurant, but due to the poor acoustics, the whole
surrounding can become an ugly noisy place.
● The poor acoustics will double the noise and customers
may found quite annoying.
3. THE FACTORS AFFECTING ACOUSTIC OF RESTAURANT
• Noise is one of the most common reasons for complaints, and today we can often see
restaurant reviews that include a noise rating in addition the rating of quality of food and
service
• The acoustic of the restaurant can affect the taste of the food . The theory suggest that
noise disrupts taste and smell, and it is found that the food tastes less intense in loud
noise ( 75 dB to 85 dB ).
• The main parameters that determine the
noise level in a restaurant are the volume,
reverberation time of the space and the
number of people.
4. THE COCKTAIL PARTY EFFECT
The ability of a normal hearing person to localize a sound source in the
surrounding 3D space , it is possible to focus on one out of many voices ,
and to focus on one voice out of many voices as they are suppressed as
background noise . This is so called cocktail-party effect. However, this
ability requires normal hearing capability and people using hearing aids of
older types may not be able to separate the voices in the 3D space.
VOCAL EFFORT
The vocal effort is characterized by the A – weighted SPL 1 meter in front of
the speaker. Normal vocal effort corresponds to an SPL around 60 dB at a
distance of 1 meter . By shouting, the SPL can reach 90 dB or more, whereas
in private communication (whispering or soft speech) typical levels are below
45 dB. The vocal effort depends on the situation, the distance to the people
being addressed, but also the type of the talk, e.g. private conversation or
giving a message.
5. The Lombard effect
In a noisy gathering, everyone raises their own voice in order to be heard better, which again
leads to a higher ambient noise level. This unconscious raising of the voice in a noisy
environment is called the Lombard effect. In quiet surroundings, the vocal effort is not
influenced by the ambient noise, but if the noise level exceeds 45 dB it starts to influence the
speech level. Interestingly enough, the Lombard effect is not particular to humans, but has also
been found in other mammals and birds.
Higher ambient level Louder conversations
6. The average relationship between speech level and ambient noise level is shown in the
graph below. . If the ambient noise is increased by 6 dB, the vocal effort is expected to
increase by 3 dB. The steps of vocal effort from relaxed to shouting are labelled in the
figure.
When enjoying a good meal in a restaurant and having a private conversation, the
ambient noise (including background music) should not exceed 55 dB, as this
corresponds to normal vocal effort. However, in a busy cafeteria, the ambient noise
can typically reach 70 to 80 dB, and a conversation is only possible in a loud or very
loud voice.
7. Ambient Noise Due To Speech
• The ambient noise in a room due to many people speaking simultaneously can be predicted
by taking the Lombard effect into account. The result is that the noise decreases by 6 dB if
the number of speaking persons is halved or if the reverberation time is halved.
• This may be a little surprising, because we normally have only 3 dB reduction of the noise if
the reverberation time is halved. So, adding more sound absorption to the room surfaces is
quite efficient; doubling the absorption area will also lead to a 6 dB reduction of the
ambient noise level with the same number of speaking persons.
• It has also been found that, in restaurants and banquet halls, the average number of
speaking people is the total number of people divided by 3 to 5 . You could say that the
average group size around each speaking person is between 3 and 4 people.
8. When listening to a conversation, the SPL of the voice should preferably exceed the SPL of the
ambient noise. The difference between these two SPLs is called the signal-to-noise ratio (SNR).
If the absorption area per speaking person is 25 m2
, the SPL is 65 dB both for the ambient noise
level and for the speech level at a distance of 1 meter. Thus SNR = 0 dB.
For normal-hearing people, it may be sufficient to have SNR = -3 dB, but in other cases this will be
clearly insufficient, namely in case of elderly people with reduced hearing capability or in case of a
conversation in a foreign language.
From the graphs, we see that SNR = -3 dB corresponds
to an ambient noise level of 71 dB. In order to obtain
an SNR = -3, the absorption area should be 12.5
m2
per speaking person. If this minimum of absorption
cannot be established, the acoustics must be
characterized as insufficient, and the total number of
people in the facility should be reduced.
9. Acoustic capacity
The fact that the acoustical conditions in a restaurant depends strongly on the number of
people present, has led to the concept called ‘Acoustic capacity’. This is defined as “the
maximum number of people allowed in a room for ‘Sufficient’ quality of verbal
communication”. Thus, the acoustic capacity is the number of people that can be expected to
create a SNR = -3 dB at a distance of 1 meter, and the corresponding ambient noise level of 71
dB . The acoustic capacity of a space depends on the volume V (m3
) and the reverberation
time T (s):
This shows that there are two ways to increase the acoustic capacity. Either the volume
should be enlarged, e.g. by opening to adjacent spaces, or the reverberation time
should be decreased by adding sound absorbing material to the surfaces.
10. The graph below shows the ambient noise level as function of the occupancy relative to the acoustic
capacity. The figure also shows the SNR at a 1 meter distance and the corresponding quality of verbal
communication.
11. An example is shown in the plan drawing below. This is a multi-purpose hall with high ceiling (17 m).
The volume is 12 920 m3
and the reverberation time is 1.5 s.
The figure shows the set-up for banquet for 240 people. The round tables are 1.6 m in
diameter and seat eight people each. Because of the high ceiling, there is sufficient
volume per person. The acoustic capacity is 430. With 240 persons the estimated
ambient noise level is 66 dB and the SNR at 1 meter distance is -1 dB, which suggests
‘sufficient’ quality of verbal communication.
Source : https://odeon.dk/
12. Restaurants with one large dining room often have some of
the biggest problems with noise. That’s because sounds
tend to echo in these big rooms. Sound-absorbing hanging
baffles can dampen these echoes. Baffles are easy to
install: they only require S-hooks and lengths of chain or
wire.
Hanging baffles to minimize noise in large dining rooms
MATERIALS
13. SoundBlocker Membrane is an effective lightweight sound blocking
membrane to help soundproof ceilings and stud walls and is only 1.2 mm
thick and very flexible.
Acoustic Isolation Membrane (Wall)
The best soundproof wood types are Cork, Acoustic
Plywood, Medium Density Fiberboard (MDF) and
Oriented Strand Board (OSB).
1. Wooden Acoustic Panels
2. Fabric Acoustic Panels
The most common fabric choice for commercial panel manufacturers is
Guilford of Maine Panel Textiles. This is a high-quality material. That
being said, there are a great variety of inexpensive fabrics that can work
equally well. Colored burlap is a very common choice.
14. Quiet Batt™ 30 is a 3 in. premium,
high-performance soundproofing and thermal
insulation product designed for use in both
interior and exterior walls, ceilings and attic
applications. Quiet Batt™ 30 soundproofing
insulation installs with a tight friction fit
between wood and metal studs to minimize
sound and thermal energy transmission.
HIGHEST SOUND ISOLATION - Sound Blanket has a STC upto 28
dB, making it the most sound blocking product in the market. Best for
bass and sound control in multiplexes, auditoriums, studios, gyms,
shopping malls, banquet halls, hotels etc. All local carpenters and civil
workers can install the membrane easily on walls, floors and ceiling
using heavy duty nails and SR adhesive.
15. Class A™ anechoic
acoustic foam, basic sound
absorbing panels that can
be installed on any wall to
reduce echoes and improve
a room’s acoustic
properties.
Class A™ bass wedge
acoustic foam, deep V-cut
fire rated acoustic foam that
has been specially
designed for rooms with
poor low frequency control.
Class A™ corner trap
acoustic foam,
freestanding triangular
bass traps with a fluted
pattern for preventing low
frequency reverberations.
Class A™ pyramid
acoustic foam,
fire-resistant acoustic
foam that’s ideal for
improving sound quality in
professional recording
studios, theaters and
other large spaces.
SOURCE : https://www.soundproofcow.com/product-category/soundproofing-foam/fire-rated-acoustic-foam/
16. With melamine or natural wood veneer finish reflects the bright
and beautiful style of modern rhythm, tongue and groove board
acoustic treatments panel is an excellent product decoration
material.
Acoustic Tongue and Groove Board Installation System
(1) Light steel keel system
(2) Woo batten system
5. Grooved Acoustic Panels.
6. Wood wool Acoustic Panels. Entertainment application: KTV, hotel, bar, night club, disco,
cinema cheap sound panels. Features : 1. Made of wood wool
cement board
2. Visually pleasing
3. Thermal insulation
4. Heat preservation
5. Environment protection
6. Decorative anti sound panel
7. No formaldehyde
8. Easy to install
Source : https://www.huiacoustics.com/product-category/soundproof-doors/
17. Laminate Flooring Underlayment Acoustic Flooring Silent Flooring Underlayment
of Laminate Flooring. Common materials for acoustic flooring include
Acoustiblok, rubber based crumb, cork and felt for example.
Acoustic Flooring
Carpet or carpet tiles are known for mitigating impact sound, making them a
perfect choice for hotels, classrooms and offices. Higher pile carpets or
carpets with a thick pad underneath, are especially good at absorbing sound
and reducing transmission.
Combining carpet with resin flooring can help to insulate sound where you
need it most
18. Cork Flooring
Cork flooring is a sustainable, comfortable and sound-absorbent
flooring option perfect for many commercial applications. Still, due to
its tendency to stain and indent it is often used as an underlay to
provide acoustic insulation.
Wood Plastic Composite (WPC) Flooring
Durable, waterproof and easy to maintain, WPC flooring provides great acoustic
benefits, especially when it comes to mitigating the impact noise such as high
foot traffic. Its acoustic benefits are largely drawn from its backing layer, which
not only provides sound insulation, but also protects against mold and mildew.
Like acoustic plasterboard, acoustic plaster finishes have been around
for years.
Varying ingredients, compounds and systems can increase or decrease
weight and flexibility to further reduce surface reflections and in doing so
help with equalisation of the internal acoustics.
Acoustic Plaster
19. Rubber Flooring
Commercial rubber flooring is known for its sound absorbent
qualities. More than that, it is slip-, mold- and mildew-resistant. It
is a great choice for hospitals, schools, gyms and kitchens
looking for a durable acoustic flooring material. Rubber flooring
is known for its sound absorbent qualities as well as slip and
mold resistance
Vinyl Tile
Vinyl tile, especially luxury vinyl tile (LVT) installed with a
sound-insulating underlayment, is a great resilient flooring
option used for sound treatment. It is selected by many
facilities due to its design versatility, durability and relatively
low maintenance costs. LVT with sound-insulating
underlayment is a great resilient flooring option used for
sound treatment
20. The restaurant owners at Salter’s project at Hakkasan in
San Francisco had specific acoustical requirements. The
absorbing material was black duct liner board on the
ceiling. Photo courtesy of Charles M. Salter Associates,
Inc.
● Duct Liner Board
At COV in Wayzata, Minn., Shea’s team raised the ceiling
but added wood slats and dense acoustical panels to absorb
and break up the sound. The open kitchen and bar provide
white noise. Photograph by Travis Anderson
● Dense acoustical
panels
21. Salter’s project, Boudin at the Wharf in San Francisco, has
a sound-absorbing metal deck to absorb sound bouncing
off the ceiling. Photo courtesy of Charles M. Salter
Associates, Inc.
● Sound absorbing
metal deck
Built in the 1980s, a kiln-dried-cedar slat ceiling with
sound-absorbing material was installed at Mudd’s restaurant
in San Ramon, Calif., in order to control reverberation.
Photo courtesy of Charles M. Salter Associates, Inc.
Source :
https://rddmag.com/design/1091-restaurant-acoustics#:~:text=Adding%20wood%20slats%20to%20a,also%20works%20to%20control%20reverberations.&text=Many%20res
taurants%20contain%20hard%20surfaces,linen%2Dcovered%20walls%20dampen%20noise.
23. DESCRIPTION
❑ Ceiling clouds are a very effective treatment
for the reduction of sound in building areas.
❑ The cloudsorba not only allows one to
achieve excellent acoustic results but also
give superb visual characteristics.
❑ Cloudsorba can be manufactured upto the
size of 2700 mm x 1200 mm.
❑ The acoustic fabric is bonded to the face and
around all four sides to give a superb
frameless appearance.
FIRE RESISTANT
Cloudsorba recycled glass wool acoustic board
provides very good fire resistant properties.
WEIGHT
3 KG/SQ.M
MAINTENANCE
❑ The Cloudsorba hanging panels can be cleaned using a
vaccum cleaner.
❑ Any slight dirt marks may be cleaned with a damp cloth
or a proprietary cleaner.
24. INSTALLATION:
❑ The panel system will come with the spiral
springs,2 m cables and the eyelet hooks.
❑ Installation time is fast as the cloudsorba
acoustic panels are simply suspended by
steel wires from the soffit by means of
special spiral hooks which are fitted in the
rear of the acoustic panels.
❑ The depth in suspension is simply adjusted
by adjusting the length of the steel
suspension wire.
❑ This also allows the panels to be installed
❑ At sloping angles if required,again adding
to the visual design possibilities.
❑ The spiral hooks should be placed between
200 mm to 300 mm from the edge of the
panels.
❑ For sloping panel installations, recommend
the largest panels to be no more than 700
mm x 700 mm.
SOURCE:http://www.soundsorba.com/
26. DESCRIPTION
Wallsorba acoustic panels are used to reduce
reverberant noise levels in buildings.
Wallsorba panels are transform a stark,echoing area
into a warm,quitercongential work place.
If required, small display posters can be pinned to
panels.
WEIGHT
The 25 mm thk wallsorba weight approximately 3 kg/m2.
The 40 mm thk wallsorba weight approximately 4 kg/m2.
UPVC trims weight approx. 1kg/length.
Walls and ceiling surfaces must be flat and level.
CUTTING
Wallsorba panels can be cut with a sharp kitchen or
stanely knife.
27. TEE JOINT PANEL SYSTEM
INTRODUCTION:
❑ This is the most economical panel utilizing white UPVC
fixing section.
❑ The panel have cut edges on all four sides.
❑ The UPVC section serves two functions.One is to
decorative the mask the edges and the other is as
structural fixing sections.
❑ This system is the most flexible as panels can be cut on
site to suite wall dimensions.
NOMINAL DIMENSIONS:
Panel size: 2700mmx1200mm
Panel thickness: 25mm-40mm
UPVC fixing trims: 2700 mm lengths
28. FIXING GUIDE:
❑ Screwfix UPVC female perimeter trim to top,bottom
and end of walls.
❑ Screwfix UPVC female T joint. Trim vertically
between top and bottom UPVC female perimeter
trims ,allowing for panel width and height.
❑ Cut and insert individual panels to fit between the
female perimeter and female T joint trims.
❑ Push fit top and bottom male perimeter trims into
female trims.
❑ They neatly cut vertical male perimeter and vertical
male T joint trims to fit between the top and bottom
perimeter trims and push fit together.
❑ Ensure that all trims are fully push in and located
❑ On external corners, glue the PL50 angle trim as
illustrated above.
29. BUTT JOINT PANEL SYSTEM
INTRODUCTION:
❑ This eliminates the requirement of a tee
joint section as this panel has reinforced
long edges and the fabric facing is
wrapped around the two long edges of
the panel.
❑ This results in a neat,crisp butt joint
between the panels.
NOMINAL DIMENSIONS
Panel size: 2700mm x 1200mm
Panel thickness: 25 mm-40mm
UPVC fixing trims: 2700mm lengths
30. FIXING GUIDE:
❑ Screw fix UPVC female perimeter trim to top,bottom
and end of walls.
❑ Cut panels to size.Position individual butt joint panels
to fit between the female perimeter trims.Ensure the
visible panels butt joints are tight and straight.
❑ Remove panels away from wall and spray 12 inch
horizontal band of gluesorba spray as adhesive.This
should be done about half way down the height of the
back of the panel.
❑ Then spray a similar band on the corresponding
position on the wall so it coincides with the glue
positions on back of the panel.Allow adhesive dry for
approximately 2 to 5 minutes.
❑ Carefully reposition the panels in the original
positions.
❑ Push fit top, bottom and end male perimeter trims
into female trims.
❑ Ensure that all trims and panels are fully pushed in and
located.
❑ On external corners,glue the PL50 angle trim as shown
in the above diagram.
SOURCE:http://www.soundsorba.com/
31. Restaurant : Gill’s Diner
Location : Melbourne, VIC
Designer : Phil Burns, MArch , RMIT
Gill’s Diner is an industrial space with high ceilings and many
parallel, acoustic reflective surfaces such as concrete and glass.
Knauf Stratopanel (Cleaneo) high in roof to absorb some of the
sound bouncing between the beams. All tables clad in red- flocked
cleaneo , that gently curve at the top to cuddle the patrons, The seat
backs also functions as an acoustic barrier, to sound created at that
table and those surroundings.
Source :
https://knauf.solutions/wp-content/uploads/eBooks/Knauf_e-book_Acoustic_Desi
gn_for_Restaurants_Web.pdf
CASE STUDY
