THE ACOUSTIC ANALYSIS OF THE OLD SENATE CHAMBER
BY
ODOGUN OLAWOLE STEPHEN
ARC097399
MEKULEYI OLABODE
ARC097396
SUBMITTED TO
THE FEDERAL UNIVERSITY OF TECHNOLOFY AKURE
THE DEPARTMENT OF ARCHITECTURE
COURSE CODE ARC 507
COURSE TITLE ENVIRONMENTAL CONTROL III
(ACOUSTICS AND NOISE CONTROL)
COURSE LECTURER PROF OLU OLA OGUNSOTE
JULY 2014
10 INTRODUCTION 1
20 DESCRIPTION OF THE OLD SENATE CHAMBER 1
21 Location 1
22 Architectural Design of building 2
221 Wall finishes 3
222 Floor finishes 4
223 Ceiling finishes 4
224 Fenestrations 5
225 Furniture 5
30 VIEWS OF THE SEATING ARRANGEMENT 6
31 SOURCES OF INTERNAL AND EXTERNAL NOISE IN THE
OLD SENATE CHAMBER 7
32 SOURCES OF OUTDOOR NOISE 8
40 ASSESSMENT OF THE ACOUSTIC CHARACTERISTICS OF
THE OLD SENATE CHAMBER 9
50 PROPOSAL FOR IMPROVING THE ACOUSTICS OF THE OLD
SENATE CHAMBER 11
51 REDUCTION OF INTERNAL NOISE 11
52 REDUCTION OF EXTERNAL NOISE 12
60 CONCLUSION 12
70 REFERENCES 13
10 INTRODUCTION
The studying of the acoustic properties of a building is as important as the buildings form itself
function and structure which is defined analyzed and prescribed according to the use to which
the room space or building is put to Various spaces within a building has various purposes ie
living room theatre studio dinning bedroom etc which leads to the acoustic variation within
the spaces but it is treated as one single entity of the total building Acoustic
Paying close attention to the acoustics properties of a particular space before or after construction
is important also in terms of knowing the kind of materials to use on the floor wall furniture
( general finishes) etc in that particular space
20 DESCRIPTION OF THE OLD SENATE CHAMBER
The old senate chamber is a room in the senate building of the federal university of technology
Akure used as the legislative chamber of the university but now old chamber as new one has
been constructed in the senate extension besides the new old senate building The room also
serves as the Supreme Court chamber of the university where various issues are trashed out
21 LOCATION OF THE CHAMBER
The old senate chamber is located at the first floor of the main senate building located at the
center heart of the school in Oba-nla region of the FUTA campus with ldquovehicular circulation
routerdquo from obakekere north gate coming from the Ilesha- Ibadan express way the School of
Environmental technology School of Engineering and Engineering Technology and has its
nearest neighbors to be the Student affairs building- which is directly opposite it the Theodore
Idibiye auditorium bank area motion ground and also the Student union building The
environment is blessed with green vegetation of well-maintained grasses flowers etc
pg 1
22 ARCHITECTURAL DESIGN HISTORY OF FUTA SENATE BUILDING
The buildingrsquos design aligns with the contemporary trend of architecture as it embodies the
salient elements of architectural design in this modern era even though itrsquos not a twenty first
century building These governing elements span from materials of construction to type and
property of finishes etc used in the design The building is predominantly the most Important
building in the university as all major decisions are made in the building and the building also
houses some of the most important personality of the university ranging from the vice
chancellor deputy vice chancellor and a host of notable offices like admission office
examination office to mention a few The building has 3 floors and a pent floor that makes it 4
floors and has a massive car parking opposite it plus its extension seating directly beside it
For the purpose of the Couse we will be concentrating on the first floor which is the section of
the senate building that houses the old senate chamber Acoustics properties of the room (interior
and exterior) will be considered particularly the materials finishes of the interior wall and
exterior wall floor finishes ceiling finishes etc
FLOORPLAN AND OF THE OLD
SENATE CHAMBER (INTERNAL)
pg 2
PLATE 1
Wooden furnitures
SITE PLAN SHOWING EXTERNAL SOURCES OF NOISE
221 WALL FINISHES
The walls fall into two categories the interior walls and the exterior walls The interiors walls
are designed with hollow sand-crete blocks with a layer of mortar plastering which is finished
with coating of light coloured cream emulsion paints The acoustic property of sand-crete blocks
rendered with cement plaster has a pretty low absorption co-efficient
The exterior walls are also constructed with sand-crete blocks with a layer of mortar screed and
they are finished with textcoat paints which are also light coloured cream The roughness the
pg 3
PLATE 2
surface improves its acoustic quality because Rough walls tend to diffuse sound reflecting it in
a variety of directions Hence very little sound can be absorbed from out noise sources and
transmitted into the building and coupled with the fact that itrsquos almost a secluded area with little
movement around without a real purpose
222 FLOOR FINISHES
The floors of the spaces in the buildings are finished with deep polished terrazzo floor finish
This is quite poor as an acoustic material since terrazzo has a very low absorption co-efficient
002 at 1000Hz and its smooth nature reflects the sound
undesirably
But with this in mind a correction measure had
already been taking by laying of sound absorbing
material Ie rug and an underlay foam which actually
helps in reducing the echoes or reverberations of
sound whenever the room is put to use
223 CEILING FINISHES
Due to the use at which the room is put to the ceiling was finished with wooden plywood of
600x600mm and a little part finished with concrete slabs with a layer of mortar screed Wood
was used as the ceiling finish because of its acoustics capabilities wood produces sound by
direct striking and can amplify or absorb sound waves
originating from other bodies For these reasons itrsquos a
unique material for musical instruments and other
acoustics applications like that itrsquos used for at the old
senate chamber because when sound waves of extrinsic
origin strike wood they partly absorbed and partly
pg 4
PLATE 4
PLATE 3
reflected and the wood is set in vibration
NOTE normally wood absorbs a very small portion of acoustic energy (3-5percent) but
special constructions incorporating empty spaces and porous insulation boards can
increase absorption to as high as 90percent
224 FENESTRATIONS
The amount of openings in a space is referred to as Fenestration It is a critical feature in
acoustic considerations in buildings The shape type and size of the fenestrations are parameters
that shouldnrsquot be undermined in takingnoting architectural acoustics The windows in the old
senate chamber are made from glass and they are fixed type The windows are of 300mm height
but span the whole of the room at the bottom and top side of the room with the only movable
window been the windows at the podium of the chamber which are often locked as well They
are framed with aluminum mullions The two doors in the chamber are also made of tempered
glass of between 8mm-10mm thick glass framed with aluminum mullions and are all double leaf
swing doors of 900 x 2100mm per leaf
The windows are predominantly used for lighting but not
for ventilation purposes as the major ventilation in the chamber
are artificial hence they are always left locked The closed
window then disallows and reduces external noise to
Impinge the internal spaces
225 FURNITURE
The furniture in the spaces under consideration goes with the use The basic furniture types are
the plywood drawing boards there are also wooded chairs with cloth cladding and heavy timber
deskscabinets Wood generally is a good absorber of sound but that is not enough to improve the
acoustics of the room to an appreciable level also The acoustics of the chamber may be very
pg 5
PLATE 5
different when it is full from when it is empty empty seats reflect sound whereas an audience
absorbs sound
30 VIEW OF THE SEATING AND AUDIO VISUAL ARRANGEMENT IN THE
CHAMBER
pg 6
PLATE 6
stage areadirect sound
reverberated sound
Absorbed sound
seating area
Reverberated sound
PLATE 7 The interior view elevation
31 SOURCES OF INTERNAL AND EXTERNAL NOISE IN THE OLD SENATE
CHAMBER
In the process of analyzing the acoustics properties of the old senate chamber we analyze the
noise source both from the internal and external sources the noise from external areas ndashwhich is
commonly referred to as outdoor noise And noise from the internal spaces and from the
interactions- which are also referred to as indoor noise
These two categories would be considered in detail with the senate building as study
32 SOURCES OF OUTDOOR NOISE
1048707 VEHICULAR TRAFFIC Vehicles generate noise as they are driven in and out of the senate
area most especially close to the senate chamber itself at the lower floor Noise from the roads
opposite the chamber going to the auditorium possess several challenges most especially when a
program is been held at the auditorium the up and down movement of cars also increase the
noise in the environment But due to the low fenestration of the chamber it has a very
minimal effect on the interior as background noise
1048707 PEDESTRIAN AND CIRCULATION IN WALKWAYS since the senate building itself is
located in the busy bank area of the school pedestrian movement from different sources causes
much noise to the chamber This is also a disadvantage to the acoustic of the room most
especially because the senate chamber is located close to this pedestrian route Chatting shouting
and general sounds are part of the activities that produce the noise that is disseminated from the
pedestrian access roads also in the senate circulation area around the chamber pedestrian
pg 7
movement though restricted in a way still affects the acoustics of the room But again reduction
in the openings aids the room by reducing the noise from outside to its barest minimum
1048707 MECHANICAL NOISE FROM FUTA FM ELECTRICITY GENERATING PLANT
AND AC
The Futa FM generator is located near the old senate chamber and power outage during the day
causes the generator to be turned on hence noxious sounds are disseminated from this massive
plant due to ageing
Secondly the noises from the window unit AC around the chamber in the senate building also
add to the noise level
32 SOURCES OF INDOOR NOISE
bull Audience noise this is the noise that is usually disseminated from the audience in the room ie
the chamber users (students when invited for panel or other matters and lecturers both teaching
and non-teaching depending on the purpose of the use) this problem of audience is
fundamentally inevitable in acoustics as the users of the building must make sounds of different
sorts which could be as a result of talking coughing ringing of phones etc Though this effect is
at the minimum due to the materials used in the finishes of the room that absorb those sound
bull Mechanical noise
These are noise from the mechanical appliances in the room noise from the split unit ac and the
ceiling fans which is almost a constant source of noise in the room due to the fact that there is
pg 8
little or no natural ventilation in the room the only openings in the room are for lighting and not
ventilation which has both negative and positive impact on the room This are the two major
source of noise in the old senate chamber all other sources that could be found or associated
with the room has been taking care of with use of rugs wooden furniture foam
underlay wooden ceiling etc
40 ASSESSMENT OF THE ACOUSTIC CHARACTERISTICS OF THE OLD SENATE
CHAMBER - EFFECTS OF THE INTERNAL AND EXTERNAL SOURCES OF NOISE
The acoustics characteristics of the space can be described under the following headings
The Background noise (external sources)
Reverberation and Echoes (Internal sources)
THE BACKGROUND NOISE
The Background noise that is transmitted into the interior spaces of the building has been
shielded and reduced to its barest minimum to a very good extent with the location of the
chamber in a less traffic area of the senate on the first floor the use of thick glass fixed windows
which has reduced the noise from the background leaving just the door as the only major
opening in the room All other sources of background noise like generators window unit ac
pedestrian movement etc affects majorly only when the doors are opened which is on a
minimal occasion
pg 9
REVERBERATION AND ECHOES
Reverberation is the persistence of sound in an enclosed space due to repeated reflection or
scattering after the sound source has stopped
Echo is a reflection of sound in a large room It is a distinct repetition of the original sound
though it is fainter because not all original sound is reflected
The design of the interiors space in the chamber is such that each person has a direct line of
auditory perception because of the way the room is constructed with stepped levels of seats
Although the walls surfaces are smooth and aids reflection the reverberation time is such that
speech is intelligent in the building
The materials used in the interior space are acoustics inclined For example the floor was ruged
and thick foam underlay layed under the rug which as a good sound absorbing ability the
ceiling materials for the sitting area are made of sound absorbing materials (wood) thus reducing
reflection However it is of note that echoes arenrsquot usually experienced in the room even though
the wall is of a smooth emulsion material
Note Reverberation is less when the room is put to use ie contains people because their bodies
absorb the sand waves and it also reduces the intensity of the sound but due to the cascading of
the seats it will not a be a problem because each person seated in row s will be able to hear well
without obstruction
pg 10
50 PROPOSAL FOR IMPROVING THE ACOUSTICS OF THE OLD SENATE
CHAMBER
This proposal is going to address this issue through two channels which would be methods of
reducing internal noise and methods of reducing external noise
51 REDUCTION OF INTERNAL NOISE
Basically the major acoustics materials that are meant to be put in place are already there ie the
floor material the ceiling etc but few things still needs to be checked and it listed as follows
1048707 Use of textured walls making the walls in the room a rough wall will help to diffuse the
sound coming from the speaker because the direct sound is disseminated around the room when
it impacts on these wall surfaces Hence a sensation of an ominous sound is heard A smooth
surface converges the sound to a point thereby distorting it Materials like cork particle board
felt wall carpets or wall papers help diminish internal noise in the space
1048707 Ceiling Finishes itrsquos important to cover the concrete part of the room with the use of the
suspended type of ceiling covering to create a void between the concrete slab and the space
below White perforated gypsum acoustic suspended ceiling boards could be used as a finish or
wood as used in other parts of the ceiling
1048707Installation of good AC unit with good silencer to replace the ceiling fans
The installation of more air-conditioning unit will eliminate the ceiling fan which reduces the
sound produced by the ceiling fan However these AC units should be sound proof to avoid
pg 11
generating noise and the already installed could be changed or serviced when necessary to
eliminate sound it might produce due to servicing
1048707full upholstery of seats Some seats have been replaced by a plastic chairs due to maybe
dilapidation of the former ones but they need to replace them back with full upholstery seats
52 REDUCTION OF EXTERNAL NOISE
Itrsquos deduced after considering the acoustics correction steps the major ways of rectifying the
external noise has already been put in place which is the insulation of the space the only thing
needed is that of the maintenance of the acoustics materials (thick glass n textured paints where
necessary) in case of damage and the use of textured wall like that of the interior
60 CONCLUSION
During the course of this research we can deduce that the treatment of the interior compartment
of any building most especially a room that is to be used as an auditorium is a very sensitive one
and should be monitored from start to finish ie from construction level to finish level Acoustics
studying of the senate chamber as helped in various ways and it will definitely have effects on
our careers both now and in the future Its successes and failure in buildings noise sources and
control and ways of apply it during design are well understood now to a better extent
pg 12
70 REFERENCES
Prof Olu Ola Ogunsote Acoustics and noise control lecture notes
Diamant RME (1986) Thermal and acoustic insulation University Press Cambridge
httpwwwsdngnetcom
pg 13
10 INTRODUCTION 1
20 DESCRIPTION OF THE OLD SENATE CHAMBER 1
21 Location 1
22 Architectural Design of building 2
221 Wall finishes 3
222 Floor finishes 4
223 Ceiling finishes 4
224 Fenestrations 5
225 Furniture 5
30 VIEWS OF THE SEATING ARRANGEMENT 6
31 SOURCES OF INTERNAL AND EXTERNAL NOISE IN THE
OLD SENATE CHAMBER 7
32 SOURCES OF OUTDOOR NOISE 8
40 ASSESSMENT OF THE ACOUSTIC CHARACTERISTICS OF
THE OLD SENATE CHAMBER 9
50 PROPOSAL FOR IMPROVING THE ACOUSTICS OF THE OLD
SENATE CHAMBER 11
51 REDUCTION OF INTERNAL NOISE 11
52 REDUCTION OF EXTERNAL NOISE 12
60 CONCLUSION 12
70 REFERENCES 13
10 INTRODUCTION
The studying of the acoustic properties of a building is as important as the buildings form itself
function and structure which is defined analyzed and prescribed according to the use to which
the room space or building is put to Various spaces within a building has various purposes ie
living room theatre studio dinning bedroom etc which leads to the acoustic variation within
the spaces but it is treated as one single entity of the total building Acoustic
Paying close attention to the acoustics properties of a particular space before or after construction
is important also in terms of knowing the kind of materials to use on the floor wall furniture
( general finishes) etc in that particular space
20 DESCRIPTION OF THE OLD SENATE CHAMBER
The old senate chamber is a room in the senate building of the federal university of technology
Akure used as the legislative chamber of the university but now old chamber as new one has
been constructed in the senate extension besides the new old senate building The room also
serves as the Supreme Court chamber of the university where various issues are trashed out
21 LOCATION OF THE CHAMBER
The old senate chamber is located at the first floor of the main senate building located at the
center heart of the school in Oba-nla region of the FUTA campus with ldquovehicular circulation
routerdquo from obakekere north gate coming from the Ilesha- Ibadan express way the School of
Environmental technology School of Engineering and Engineering Technology and has its
nearest neighbors to be the Student affairs building- which is directly opposite it the Theodore
Idibiye auditorium bank area motion ground and also the Student union building The
environment is blessed with green vegetation of well-maintained grasses flowers etc
pg 1
22 ARCHITECTURAL DESIGN HISTORY OF FUTA SENATE BUILDING
The buildingrsquos design aligns with the contemporary trend of architecture as it embodies the
salient elements of architectural design in this modern era even though itrsquos not a twenty first
century building These governing elements span from materials of construction to type and
property of finishes etc used in the design The building is predominantly the most Important
building in the university as all major decisions are made in the building and the building also
houses some of the most important personality of the university ranging from the vice
chancellor deputy vice chancellor and a host of notable offices like admission office
examination office to mention a few The building has 3 floors and a pent floor that makes it 4
floors and has a massive car parking opposite it plus its extension seating directly beside it
For the purpose of the Couse we will be concentrating on the first floor which is the section of
the senate building that houses the old senate chamber Acoustics properties of the room (interior
and exterior) will be considered particularly the materials finishes of the interior wall and
exterior wall floor finishes ceiling finishes etc
FLOORPLAN AND OF THE OLD
SENATE CHAMBER (INTERNAL)
pg 2
PLATE 1
Wooden furnitures
SITE PLAN SHOWING EXTERNAL SOURCES OF NOISE
221 WALL FINISHES
The walls fall into two categories the interior walls and the exterior walls The interiors walls
are designed with hollow sand-crete blocks with a layer of mortar plastering which is finished
with coating of light coloured cream emulsion paints The acoustic property of sand-crete blocks
rendered with cement plaster has a pretty low absorption co-efficient
The exterior walls are also constructed with sand-crete blocks with a layer of mortar screed and
they are finished with textcoat paints which are also light coloured cream The roughness the
pg 3
PLATE 2
surface improves its acoustic quality because Rough walls tend to diffuse sound reflecting it in
a variety of directions Hence very little sound can be absorbed from out noise sources and
transmitted into the building and coupled with the fact that itrsquos almost a secluded area with little
movement around without a real purpose
222 FLOOR FINISHES
The floors of the spaces in the buildings are finished with deep polished terrazzo floor finish
This is quite poor as an acoustic material since terrazzo has a very low absorption co-efficient
002 at 1000Hz and its smooth nature reflects the sound
undesirably
But with this in mind a correction measure had
already been taking by laying of sound absorbing
material Ie rug and an underlay foam which actually
helps in reducing the echoes or reverberations of
sound whenever the room is put to use
223 CEILING FINISHES
Due to the use at which the room is put to the ceiling was finished with wooden plywood of
600x600mm and a little part finished with concrete slabs with a layer of mortar screed Wood
was used as the ceiling finish because of its acoustics capabilities wood produces sound by
direct striking and can amplify or absorb sound waves
originating from other bodies For these reasons itrsquos a
unique material for musical instruments and other
acoustics applications like that itrsquos used for at the old
senate chamber because when sound waves of extrinsic
origin strike wood they partly absorbed and partly
pg 4
PLATE 4
PLATE 3
reflected and the wood is set in vibration
NOTE normally wood absorbs a very small portion of acoustic energy (3-5percent) but
special constructions incorporating empty spaces and porous insulation boards can
increase absorption to as high as 90percent
224 FENESTRATIONS
The amount of openings in a space is referred to as Fenestration It is a critical feature in
acoustic considerations in buildings The shape type and size of the fenestrations are parameters
that shouldnrsquot be undermined in takingnoting architectural acoustics The windows in the old
senate chamber are made from glass and they are fixed type The windows are of 300mm height
but span the whole of the room at the bottom and top side of the room with the only movable
window been the windows at the podium of the chamber which are often locked as well They
are framed with aluminum mullions The two doors in the chamber are also made of tempered
glass of between 8mm-10mm thick glass framed with aluminum mullions and are all double leaf
swing doors of 900 x 2100mm per leaf
The windows are predominantly used for lighting but not
for ventilation purposes as the major ventilation in the chamber
are artificial hence they are always left locked The closed
window then disallows and reduces external noise to
Impinge the internal spaces
225 FURNITURE
The furniture in the spaces under consideration goes with the use The basic furniture types are
the plywood drawing boards there are also wooded chairs with cloth cladding and heavy timber
deskscabinets Wood generally is a good absorber of sound but that is not enough to improve the
acoustics of the room to an appreciable level also The acoustics of the chamber may be very
pg 5
PLATE 5
different when it is full from when it is empty empty seats reflect sound whereas an audience
absorbs sound
30 VIEW OF THE SEATING AND AUDIO VISUAL ARRANGEMENT IN THE
CHAMBER
pg 6
PLATE 6
stage areadirect sound
reverberated sound
Absorbed sound
seating area
Reverberated sound
PLATE 7 The interior view elevation
31 SOURCES OF INTERNAL AND EXTERNAL NOISE IN THE OLD SENATE
CHAMBER
In the process of analyzing the acoustics properties of the old senate chamber we analyze the
noise source both from the internal and external sources the noise from external areas ndashwhich is
commonly referred to as outdoor noise And noise from the internal spaces and from the
interactions- which are also referred to as indoor noise
These two categories would be considered in detail with the senate building as study
32 SOURCES OF OUTDOOR NOISE
1048707 VEHICULAR TRAFFIC Vehicles generate noise as they are driven in and out of the senate
area most especially close to the senate chamber itself at the lower floor Noise from the roads
opposite the chamber going to the auditorium possess several challenges most especially when a
program is been held at the auditorium the up and down movement of cars also increase the
noise in the environment But due to the low fenestration of the chamber it has a very
minimal effect on the interior as background noise
1048707 PEDESTRIAN AND CIRCULATION IN WALKWAYS since the senate building itself is
located in the busy bank area of the school pedestrian movement from different sources causes
much noise to the chamber This is also a disadvantage to the acoustic of the room most
especially because the senate chamber is located close to this pedestrian route Chatting shouting
and general sounds are part of the activities that produce the noise that is disseminated from the
pedestrian access roads also in the senate circulation area around the chamber pedestrian
pg 7
movement though restricted in a way still affects the acoustics of the room But again reduction
in the openings aids the room by reducing the noise from outside to its barest minimum
1048707 MECHANICAL NOISE FROM FUTA FM ELECTRICITY GENERATING PLANT
AND AC
The Futa FM generator is located near the old senate chamber and power outage during the day
causes the generator to be turned on hence noxious sounds are disseminated from this massive
plant due to ageing
Secondly the noises from the window unit AC around the chamber in the senate building also
add to the noise level
32 SOURCES OF INDOOR NOISE
bull Audience noise this is the noise that is usually disseminated from the audience in the room ie
the chamber users (students when invited for panel or other matters and lecturers both teaching
and non-teaching depending on the purpose of the use) this problem of audience is
fundamentally inevitable in acoustics as the users of the building must make sounds of different
sorts which could be as a result of talking coughing ringing of phones etc Though this effect is
at the minimum due to the materials used in the finishes of the room that absorb those sound
bull Mechanical noise
These are noise from the mechanical appliances in the room noise from the split unit ac and the
ceiling fans which is almost a constant source of noise in the room due to the fact that there is
pg 8
little or no natural ventilation in the room the only openings in the room are for lighting and not
ventilation which has both negative and positive impact on the room This are the two major
source of noise in the old senate chamber all other sources that could be found or associated
with the room has been taking care of with use of rugs wooden furniture foam
underlay wooden ceiling etc
40 ASSESSMENT OF THE ACOUSTIC CHARACTERISTICS OF THE OLD SENATE
CHAMBER - EFFECTS OF THE INTERNAL AND EXTERNAL SOURCES OF NOISE
The acoustics characteristics of the space can be described under the following headings
The Background noise (external sources)
Reverberation and Echoes (Internal sources)
THE BACKGROUND NOISE
The Background noise that is transmitted into the interior spaces of the building has been
shielded and reduced to its barest minimum to a very good extent with the location of the
chamber in a less traffic area of the senate on the first floor the use of thick glass fixed windows
which has reduced the noise from the background leaving just the door as the only major
opening in the room All other sources of background noise like generators window unit ac
pedestrian movement etc affects majorly only when the doors are opened which is on a
minimal occasion
pg 9
REVERBERATION AND ECHOES
Reverberation is the persistence of sound in an enclosed space due to repeated reflection or
scattering after the sound source has stopped
Echo is a reflection of sound in a large room It is a distinct repetition of the original sound
though it is fainter because not all original sound is reflected
The design of the interiors space in the chamber is such that each person has a direct line of
auditory perception because of the way the room is constructed with stepped levels of seats
Although the walls surfaces are smooth and aids reflection the reverberation time is such that
speech is intelligent in the building
The materials used in the interior space are acoustics inclined For example the floor was ruged
and thick foam underlay layed under the rug which as a good sound absorbing ability the
ceiling materials for the sitting area are made of sound absorbing materials (wood) thus reducing
reflection However it is of note that echoes arenrsquot usually experienced in the room even though
the wall is of a smooth emulsion material
Note Reverberation is less when the room is put to use ie contains people because their bodies
absorb the sand waves and it also reduces the intensity of the sound but due to the cascading of
the seats it will not a be a problem because each person seated in row s will be able to hear well
without obstruction
pg 10
50 PROPOSAL FOR IMPROVING THE ACOUSTICS OF THE OLD SENATE
CHAMBER
This proposal is going to address this issue through two channels which would be methods of
reducing internal noise and methods of reducing external noise
51 REDUCTION OF INTERNAL NOISE
Basically the major acoustics materials that are meant to be put in place are already there ie the
floor material the ceiling etc but few things still needs to be checked and it listed as follows
1048707 Use of textured walls making the walls in the room a rough wall will help to diffuse the
sound coming from the speaker because the direct sound is disseminated around the room when
it impacts on these wall surfaces Hence a sensation of an ominous sound is heard A smooth
surface converges the sound to a point thereby distorting it Materials like cork particle board
felt wall carpets or wall papers help diminish internal noise in the space
1048707 Ceiling Finishes itrsquos important to cover the concrete part of the room with the use of the
suspended type of ceiling covering to create a void between the concrete slab and the space
below White perforated gypsum acoustic suspended ceiling boards could be used as a finish or
wood as used in other parts of the ceiling
1048707Installation of good AC unit with good silencer to replace the ceiling fans
The installation of more air-conditioning unit will eliminate the ceiling fan which reduces the
sound produced by the ceiling fan However these AC units should be sound proof to avoid
pg 11
generating noise and the already installed could be changed or serviced when necessary to
eliminate sound it might produce due to servicing
1048707full upholstery of seats Some seats have been replaced by a plastic chairs due to maybe
dilapidation of the former ones but they need to replace them back with full upholstery seats
52 REDUCTION OF EXTERNAL NOISE
Itrsquos deduced after considering the acoustics correction steps the major ways of rectifying the
external noise has already been put in place which is the insulation of the space the only thing
needed is that of the maintenance of the acoustics materials (thick glass n textured paints where
necessary) in case of damage and the use of textured wall like that of the interior
60 CONCLUSION
During the course of this research we can deduce that the treatment of the interior compartment
of any building most especially a room that is to be used as an auditorium is a very sensitive one
and should be monitored from start to finish ie from construction level to finish level Acoustics
studying of the senate chamber as helped in various ways and it will definitely have effects on
our careers both now and in the future Its successes and failure in buildings noise sources and
control and ways of apply it during design are well understood now to a better extent
pg 12
70 REFERENCES
Prof Olu Ola Ogunsote Acoustics and noise control lecture notes
Diamant RME (1986) Thermal and acoustic insulation University Press Cambridge
httpwwwsdngnetcom
pg 13
10 INTRODUCTION
The studying of the acoustic properties of a building is as important as the buildings form itself
function and structure which is defined analyzed and prescribed according to the use to which
the room space or building is put to Various spaces within a building has various purposes ie
living room theatre studio dinning bedroom etc which leads to the acoustic variation within
the spaces but it is treated as one single entity of the total building Acoustic
Paying close attention to the acoustics properties of a particular space before or after construction
is important also in terms of knowing the kind of materials to use on the floor wall furniture
( general finishes) etc in that particular space
20 DESCRIPTION OF THE OLD SENATE CHAMBER
The old senate chamber is a room in the senate building of the federal university of technology
Akure used as the legislative chamber of the university but now old chamber as new one has
been constructed in the senate extension besides the new old senate building The room also
serves as the Supreme Court chamber of the university where various issues are trashed out
21 LOCATION OF THE CHAMBER
The old senate chamber is located at the first floor of the main senate building located at the
center heart of the school in Oba-nla region of the FUTA campus with ldquovehicular circulation
routerdquo from obakekere north gate coming from the Ilesha- Ibadan express way the School of
Environmental technology School of Engineering and Engineering Technology and has its
nearest neighbors to be the Student affairs building- which is directly opposite it the Theodore
Idibiye auditorium bank area motion ground and also the Student union building The
environment is blessed with green vegetation of well-maintained grasses flowers etc
pg 1
22 ARCHITECTURAL DESIGN HISTORY OF FUTA SENATE BUILDING
The buildingrsquos design aligns with the contemporary trend of architecture as it embodies the
salient elements of architectural design in this modern era even though itrsquos not a twenty first
century building These governing elements span from materials of construction to type and
property of finishes etc used in the design The building is predominantly the most Important
building in the university as all major decisions are made in the building and the building also
houses some of the most important personality of the university ranging from the vice
chancellor deputy vice chancellor and a host of notable offices like admission office
examination office to mention a few The building has 3 floors and a pent floor that makes it 4
floors and has a massive car parking opposite it plus its extension seating directly beside it
For the purpose of the Couse we will be concentrating on the first floor which is the section of
the senate building that houses the old senate chamber Acoustics properties of the room (interior
and exterior) will be considered particularly the materials finishes of the interior wall and
exterior wall floor finishes ceiling finishes etc
FLOORPLAN AND OF THE OLD
SENATE CHAMBER (INTERNAL)
pg 2
PLATE 1
Wooden furnitures
SITE PLAN SHOWING EXTERNAL SOURCES OF NOISE
221 WALL FINISHES
The walls fall into two categories the interior walls and the exterior walls The interiors walls
are designed with hollow sand-crete blocks with a layer of mortar plastering which is finished
with coating of light coloured cream emulsion paints The acoustic property of sand-crete blocks
rendered with cement plaster has a pretty low absorption co-efficient
The exterior walls are also constructed with sand-crete blocks with a layer of mortar screed and
they are finished with textcoat paints which are also light coloured cream The roughness the
pg 3
PLATE 2
surface improves its acoustic quality because Rough walls tend to diffuse sound reflecting it in
a variety of directions Hence very little sound can be absorbed from out noise sources and
transmitted into the building and coupled with the fact that itrsquos almost a secluded area with little
movement around without a real purpose
222 FLOOR FINISHES
The floors of the spaces in the buildings are finished with deep polished terrazzo floor finish
This is quite poor as an acoustic material since terrazzo has a very low absorption co-efficient
002 at 1000Hz and its smooth nature reflects the sound
undesirably
But with this in mind a correction measure had
already been taking by laying of sound absorbing
material Ie rug and an underlay foam which actually
helps in reducing the echoes or reverberations of
sound whenever the room is put to use
223 CEILING FINISHES
Due to the use at which the room is put to the ceiling was finished with wooden plywood of
600x600mm and a little part finished with concrete slabs with a layer of mortar screed Wood
was used as the ceiling finish because of its acoustics capabilities wood produces sound by
direct striking and can amplify or absorb sound waves
originating from other bodies For these reasons itrsquos a
unique material for musical instruments and other
acoustics applications like that itrsquos used for at the old
senate chamber because when sound waves of extrinsic
origin strike wood they partly absorbed and partly
pg 4
PLATE 4
PLATE 3
reflected and the wood is set in vibration
NOTE normally wood absorbs a very small portion of acoustic energy (3-5percent) but
special constructions incorporating empty spaces and porous insulation boards can
increase absorption to as high as 90percent
224 FENESTRATIONS
The amount of openings in a space is referred to as Fenestration It is a critical feature in
acoustic considerations in buildings The shape type and size of the fenestrations are parameters
that shouldnrsquot be undermined in takingnoting architectural acoustics The windows in the old
senate chamber are made from glass and they are fixed type The windows are of 300mm height
but span the whole of the room at the bottom and top side of the room with the only movable
window been the windows at the podium of the chamber which are often locked as well They
are framed with aluminum mullions The two doors in the chamber are also made of tempered
glass of between 8mm-10mm thick glass framed with aluminum mullions and are all double leaf
swing doors of 900 x 2100mm per leaf
The windows are predominantly used for lighting but not
for ventilation purposes as the major ventilation in the chamber
are artificial hence they are always left locked The closed
window then disallows and reduces external noise to
Impinge the internal spaces
225 FURNITURE
The furniture in the spaces under consideration goes with the use The basic furniture types are
the plywood drawing boards there are also wooded chairs with cloth cladding and heavy timber
deskscabinets Wood generally is a good absorber of sound but that is not enough to improve the
acoustics of the room to an appreciable level also The acoustics of the chamber may be very
pg 5
PLATE 5
different when it is full from when it is empty empty seats reflect sound whereas an audience
absorbs sound
30 VIEW OF THE SEATING AND AUDIO VISUAL ARRANGEMENT IN THE
CHAMBER
pg 6
PLATE 6
stage areadirect sound
reverberated sound
Absorbed sound
seating area
Reverberated sound
PLATE 7 The interior view elevation
31 SOURCES OF INTERNAL AND EXTERNAL NOISE IN THE OLD SENATE
CHAMBER
In the process of analyzing the acoustics properties of the old senate chamber we analyze the
noise source both from the internal and external sources the noise from external areas ndashwhich is
commonly referred to as outdoor noise And noise from the internal spaces and from the
interactions- which are also referred to as indoor noise
These two categories would be considered in detail with the senate building as study
32 SOURCES OF OUTDOOR NOISE
1048707 VEHICULAR TRAFFIC Vehicles generate noise as they are driven in and out of the senate
area most especially close to the senate chamber itself at the lower floor Noise from the roads
opposite the chamber going to the auditorium possess several challenges most especially when a
program is been held at the auditorium the up and down movement of cars also increase the
noise in the environment But due to the low fenestration of the chamber it has a very
minimal effect on the interior as background noise
1048707 PEDESTRIAN AND CIRCULATION IN WALKWAYS since the senate building itself is
located in the busy bank area of the school pedestrian movement from different sources causes
much noise to the chamber This is also a disadvantage to the acoustic of the room most
especially because the senate chamber is located close to this pedestrian route Chatting shouting
and general sounds are part of the activities that produce the noise that is disseminated from the
pedestrian access roads also in the senate circulation area around the chamber pedestrian
pg 7
movement though restricted in a way still affects the acoustics of the room But again reduction
in the openings aids the room by reducing the noise from outside to its barest minimum
1048707 MECHANICAL NOISE FROM FUTA FM ELECTRICITY GENERATING PLANT
AND AC
The Futa FM generator is located near the old senate chamber and power outage during the day
causes the generator to be turned on hence noxious sounds are disseminated from this massive
plant due to ageing
Secondly the noises from the window unit AC around the chamber in the senate building also
add to the noise level
32 SOURCES OF INDOOR NOISE
bull Audience noise this is the noise that is usually disseminated from the audience in the room ie
the chamber users (students when invited for panel or other matters and lecturers both teaching
and non-teaching depending on the purpose of the use) this problem of audience is
fundamentally inevitable in acoustics as the users of the building must make sounds of different
sorts which could be as a result of talking coughing ringing of phones etc Though this effect is
at the minimum due to the materials used in the finishes of the room that absorb those sound
bull Mechanical noise
These are noise from the mechanical appliances in the room noise from the split unit ac and the
ceiling fans which is almost a constant source of noise in the room due to the fact that there is
pg 8
little or no natural ventilation in the room the only openings in the room are for lighting and not
ventilation which has both negative and positive impact on the room This are the two major
source of noise in the old senate chamber all other sources that could be found or associated
with the room has been taking care of with use of rugs wooden furniture foam
underlay wooden ceiling etc
40 ASSESSMENT OF THE ACOUSTIC CHARACTERISTICS OF THE OLD SENATE
CHAMBER - EFFECTS OF THE INTERNAL AND EXTERNAL SOURCES OF NOISE
The acoustics characteristics of the space can be described under the following headings
The Background noise (external sources)
Reverberation and Echoes (Internal sources)
THE BACKGROUND NOISE
The Background noise that is transmitted into the interior spaces of the building has been
shielded and reduced to its barest minimum to a very good extent with the location of the
chamber in a less traffic area of the senate on the first floor the use of thick glass fixed windows
which has reduced the noise from the background leaving just the door as the only major
opening in the room All other sources of background noise like generators window unit ac
pedestrian movement etc affects majorly only when the doors are opened which is on a
minimal occasion
pg 9
REVERBERATION AND ECHOES
Reverberation is the persistence of sound in an enclosed space due to repeated reflection or
scattering after the sound source has stopped
Echo is a reflection of sound in a large room It is a distinct repetition of the original sound
though it is fainter because not all original sound is reflected
The design of the interiors space in the chamber is such that each person has a direct line of
auditory perception because of the way the room is constructed with stepped levels of seats
Although the walls surfaces are smooth and aids reflection the reverberation time is such that
speech is intelligent in the building
The materials used in the interior space are acoustics inclined For example the floor was ruged
and thick foam underlay layed under the rug which as a good sound absorbing ability the
ceiling materials for the sitting area are made of sound absorbing materials (wood) thus reducing
reflection However it is of note that echoes arenrsquot usually experienced in the room even though
the wall is of a smooth emulsion material
Note Reverberation is less when the room is put to use ie contains people because their bodies
absorb the sand waves and it also reduces the intensity of the sound but due to the cascading of
the seats it will not a be a problem because each person seated in row s will be able to hear well
without obstruction
pg 10
50 PROPOSAL FOR IMPROVING THE ACOUSTICS OF THE OLD SENATE
CHAMBER
This proposal is going to address this issue through two channels which would be methods of
reducing internal noise and methods of reducing external noise
51 REDUCTION OF INTERNAL NOISE
Basically the major acoustics materials that are meant to be put in place are already there ie the
floor material the ceiling etc but few things still needs to be checked and it listed as follows
1048707 Use of textured walls making the walls in the room a rough wall will help to diffuse the
sound coming from the speaker because the direct sound is disseminated around the room when
it impacts on these wall surfaces Hence a sensation of an ominous sound is heard A smooth
surface converges the sound to a point thereby distorting it Materials like cork particle board
felt wall carpets or wall papers help diminish internal noise in the space
1048707 Ceiling Finishes itrsquos important to cover the concrete part of the room with the use of the
suspended type of ceiling covering to create a void between the concrete slab and the space
below White perforated gypsum acoustic suspended ceiling boards could be used as a finish or
wood as used in other parts of the ceiling
1048707Installation of good AC unit with good silencer to replace the ceiling fans
The installation of more air-conditioning unit will eliminate the ceiling fan which reduces the
sound produced by the ceiling fan However these AC units should be sound proof to avoid
pg 11
generating noise and the already installed could be changed or serviced when necessary to
eliminate sound it might produce due to servicing
1048707full upholstery of seats Some seats have been replaced by a plastic chairs due to maybe
dilapidation of the former ones but they need to replace them back with full upholstery seats
52 REDUCTION OF EXTERNAL NOISE
Itrsquos deduced after considering the acoustics correction steps the major ways of rectifying the
external noise has already been put in place which is the insulation of the space the only thing
needed is that of the maintenance of the acoustics materials (thick glass n textured paints where
necessary) in case of damage and the use of textured wall like that of the interior
60 CONCLUSION
During the course of this research we can deduce that the treatment of the interior compartment
of any building most especially a room that is to be used as an auditorium is a very sensitive one
and should be monitored from start to finish ie from construction level to finish level Acoustics
studying of the senate chamber as helped in various ways and it will definitely have effects on
our careers both now and in the future Its successes and failure in buildings noise sources and
control and ways of apply it during design are well understood now to a better extent
pg 12
70 REFERENCES
Prof Olu Ola Ogunsote Acoustics and noise control lecture notes
Diamant RME (1986) Thermal and acoustic insulation University Press Cambridge
httpwwwsdngnetcom
pg 13
22 ARCHITECTURAL DESIGN HISTORY OF FUTA SENATE BUILDING
The buildingrsquos design aligns with the contemporary trend of architecture as it embodies the
salient elements of architectural design in this modern era even though itrsquos not a twenty first
century building These governing elements span from materials of construction to type and
property of finishes etc used in the design The building is predominantly the most Important
building in the university as all major decisions are made in the building and the building also
houses some of the most important personality of the university ranging from the vice
chancellor deputy vice chancellor and a host of notable offices like admission office
examination office to mention a few The building has 3 floors and a pent floor that makes it 4
floors and has a massive car parking opposite it plus its extension seating directly beside it
For the purpose of the Couse we will be concentrating on the first floor which is the section of
the senate building that houses the old senate chamber Acoustics properties of the room (interior
and exterior) will be considered particularly the materials finishes of the interior wall and
exterior wall floor finishes ceiling finishes etc
FLOORPLAN AND OF THE OLD
SENATE CHAMBER (INTERNAL)
pg 2
PLATE 1
Wooden furnitures
SITE PLAN SHOWING EXTERNAL SOURCES OF NOISE
221 WALL FINISHES
The walls fall into two categories the interior walls and the exterior walls The interiors walls
are designed with hollow sand-crete blocks with a layer of mortar plastering which is finished
with coating of light coloured cream emulsion paints The acoustic property of sand-crete blocks
rendered with cement plaster has a pretty low absorption co-efficient
The exterior walls are also constructed with sand-crete blocks with a layer of mortar screed and
they are finished with textcoat paints which are also light coloured cream The roughness the
pg 3
PLATE 2
surface improves its acoustic quality because Rough walls tend to diffuse sound reflecting it in
a variety of directions Hence very little sound can be absorbed from out noise sources and
transmitted into the building and coupled with the fact that itrsquos almost a secluded area with little
movement around without a real purpose
222 FLOOR FINISHES
The floors of the spaces in the buildings are finished with deep polished terrazzo floor finish
This is quite poor as an acoustic material since terrazzo has a very low absorption co-efficient
002 at 1000Hz and its smooth nature reflects the sound
undesirably
But with this in mind a correction measure had
already been taking by laying of sound absorbing
material Ie rug and an underlay foam which actually
helps in reducing the echoes or reverberations of
sound whenever the room is put to use
223 CEILING FINISHES
Due to the use at which the room is put to the ceiling was finished with wooden plywood of
600x600mm and a little part finished with concrete slabs with a layer of mortar screed Wood
was used as the ceiling finish because of its acoustics capabilities wood produces sound by
direct striking and can amplify or absorb sound waves
originating from other bodies For these reasons itrsquos a
unique material for musical instruments and other
acoustics applications like that itrsquos used for at the old
senate chamber because when sound waves of extrinsic
origin strike wood they partly absorbed and partly
pg 4
PLATE 4
PLATE 3
reflected and the wood is set in vibration
NOTE normally wood absorbs a very small portion of acoustic energy (3-5percent) but
special constructions incorporating empty spaces and porous insulation boards can
increase absorption to as high as 90percent
224 FENESTRATIONS
The amount of openings in a space is referred to as Fenestration It is a critical feature in
acoustic considerations in buildings The shape type and size of the fenestrations are parameters
that shouldnrsquot be undermined in takingnoting architectural acoustics The windows in the old
senate chamber are made from glass and they are fixed type The windows are of 300mm height
but span the whole of the room at the bottom and top side of the room with the only movable
window been the windows at the podium of the chamber which are often locked as well They
are framed with aluminum mullions The two doors in the chamber are also made of tempered
glass of between 8mm-10mm thick glass framed with aluminum mullions and are all double leaf
swing doors of 900 x 2100mm per leaf
The windows are predominantly used for lighting but not
for ventilation purposes as the major ventilation in the chamber
are artificial hence they are always left locked The closed
window then disallows and reduces external noise to
Impinge the internal spaces
225 FURNITURE
The furniture in the spaces under consideration goes with the use The basic furniture types are
the plywood drawing boards there are also wooded chairs with cloth cladding and heavy timber
deskscabinets Wood generally is a good absorber of sound but that is not enough to improve the
acoustics of the room to an appreciable level also The acoustics of the chamber may be very
pg 5
PLATE 5
different when it is full from when it is empty empty seats reflect sound whereas an audience
absorbs sound
30 VIEW OF THE SEATING AND AUDIO VISUAL ARRANGEMENT IN THE
CHAMBER
pg 6
PLATE 6
stage areadirect sound
reverberated sound
Absorbed sound
seating area
Reverberated sound
PLATE 7 The interior view elevation
31 SOURCES OF INTERNAL AND EXTERNAL NOISE IN THE OLD SENATE
CHAMBER
In the process of analyzing the acoustics properties of the old senate chamber we analyze the
noise source both from the internal and external sources the noise from external areas ndashwhich is
commonly referred to as outdoor noise And noise from the internal spaces and from the
interactions- which are also referred to as indoor noise
These two categories would be considered in detail with the senate building as study
32 SOURCES OF OUTDOOR NOISE
1048707 VEHICULAR TRAFFIC Vehicles generate noise as they are driven in and out of the senate
area most especially close to the senate chamber itself at the lower floor Noise from the roads
opposite the chamber going to the auditorium possess several challenges most especially when a
program is been held at the auditorium the up and down movement of cars also increase the
noise in the environment But due to the low fenestration of the chamber it has a very
minimal effect on the interior as background noise
1048707 PEDESTRIAN AND CIRCULATION IN WALKWAYS since the senate building itself is
located in the busy bank area of the school pedestrian movement from different sources causes
much noise to the chamber This is also a disadvantage to the acoustic of the room most
especially because the senate chamber is located close to this pedestrian route Chatting shouting
and general sounds are part of the activities that produce the noise that is disseminated from the
pedestrian access roads also in the senate circulation area around the chamber pedestrian
pg 7
movement though restricted in a way still affects the acoustics of the room But again reduction
in the openings aids the room by reducing the noise from outside to its barest minimum
1048707 MECHANICAL NOISE FROM FUTA FM ELECTRICITY GENERATING PLANT
AND AC
The Futa FM generator is located near the old senate chamber and power outage during the day
causes the generator to be turned on hence noxious sounds are disseminated from this massive
plant due to ageing
Secondly the noises from the window unit AC around the chamber in the senate building also
add to the noise level
32 SOURCES OF INDOOR NOISE
bull Audience noise this is the noise that is usually disseminated from the audience in the room ie
the chamber users (students when invited for panel or other matters and lecturers both teaching
and non-teaching depending on the purpose of the use) this problem of audience is
fundamentally inevitable in acoustics as the users of the building must make sounds of different
sorts which could be as a result of talking coughing ringing of phones etc Though this effect is
at the minimum due to the materials used in the finishes of the room that absorb those sound
bull Mechanical noise
These are noise from the mechanical appliances in the room noise from the split unit ac and the
ceiling fans which is almost a constant source of noise in the room due to the fact that there is
pg 8
little or no natural ventilation in the room the only openings in the room are for lighting and not
ventilation which has both negative and positive impact on the room This are the two major
source of noise in the old senate chamber all other sources that could be found or associated
with the room has been taking care of with use of rugs wooden furniture foam
underlay wooden ceiling etc
40 ASSESSMENT OF THE ACOUSTIC CHARACTERISTICS OF THE OLD SENATE
CHAMBER - EFFECTS OF THE INTERNAL AND EXTERNAL SOURCES OF NOISE
The acoustics characteristics of the space can be described under the following headings
The Background noise (external sources)
Reverberation and Echoes (Internal sources)
THE BACKGROUND NOISE
The Background noise that is transmitted into the interior spaces of the building has been
shielded and reduced to its barest minimum to a very good extent with the location of the
chamber in a less traffic area of the senate on the first floor the use of thick glass fixed windows
which has reduced the noise from the background leaving just the door as the only major
opening in the room All other sources of background noise like generators window unit ac
pedestrian movement etc affects majorly only when the doors are opened which is on a
minimal occasion
pg 9
REVERBERATION AND ECHOES
Reverberation is the persistence of sound in an enclosed space due to repeated reflection or
scattering after the sound source has stopped
Echo is a reflection of sound in a large room It is a distinct repetition of the original sound
though it is fainter because not all original sound is reflected
The design of the interiors space in the chamber is such that each person has a direct line of
auditory perception because of the way the room is constructed with stepped levels of seats
Although the walls surfaces are smooth and aids reflection the reverberation time is such that
speech is intelligent in the building
The materials used in the interior space are acoustics inclined For example the floor was ruged
and thick foam underlay layed under the rug which as a good sound absorbing ability the
ceiling materials for the sitting area are made of sound absorbing materials (wood) thus reducing
reflection However it is of note that echoes arenrsquot usually experienced in the room even though
the wall is of a smooth emulsion material
Note Reverberation is less when the room is put to use ie contains people because their bodies
absorb the sand waves and it also reduces the intensity of the sound but due to the cascading of
the seats it will not a be a problem because each person seated in row s will be able to hear well
without obstruction
pg 10
50 PROPOSAL FOR IMPROVING THE ACOUSTICS OF THE OLD SENATE
CHAMBER
This proposal is going to address this issue through two channels which would be methods of
reducing internal noise and methods of reducing external noise
51 REDUCTION OF INTERNAL NOISE
Basically the major acoustics materials that are meant to be put in place are already there ie the
floor material the ceiling etc but few things still needs to be checked and it listed as follows
1048707 Use of textured walls making the walls in the room a rough wall will help to diffuse the
sound coming from the speaker because the direct sound is disseminated around the room when
it impacts on these wall surfaces Hence a sensation of an ominous sound is heard A smooth
surface converges the sound to a point thereby distorting it Materials like cork particle board
felt wall carpets or wall papers help diminish internal noise in the space
1048707 Ceiling Finishes itrsquos important to cover the concrete part of the room with the use of the
suspended type of ceiling covering to create a void between the concrete slab and the space
below White perforated gypsum acoustic suspended ceiling boards could be used as a finish or
wood as used in other parts of the ceiling
1048707Installation of good AC unit with good silencer to replace the ceiling fans
The installation of more air-conditioning unit will eliminate the ceiling fan which reduces the
sound produced by the ceiling fan However these AC units should be sound proof to avoid
pg 11
generating noise and the already installed could be changed or serviced when necessary to
eliminate sound it might produce due to servicing
1048707full upholstery of seats Some seats have been replaced by a plastic chairs due to maybe
dilapidation of the former ones but they need to replace them back with full upholstery seats
52 REDUCTION OF EXTERNAL NOISE
Itrsquos deduced after considering the acoustics correction steps the major ways of rectifying the
external noise has already been put in place which is the insulation of the space the only thing
needed is that of the maintenance of the acoustics materials (thick glass n textured paints where
necessary) in case of damage and the use of textured wall like that of the interior
60 CONCLUSION
During the course of this research we can deduce that the treatment of the interior compartment
of any building most especially a room that is to be used as an auditorium is a very sensitive one
and should be monitored from start to finish ie from construction level to finish level Acoustics
studying of the senate chamber as helped in various ways and it will definitely have effects on
our careers both now and in the future Its successes and failure in buildings noise sources and
control and ways of apply it during design are well understood now to a better extent
pg 12
70 REFERENCES
Prof Olu Ola Ogunsote Acoustics and noise control lecture notes
Diamant RME (1986) Thermal and acoustic insulation University Press Cambridge
httpwwwsdngnetcom
pg 13
SITE PLAN SHOWING EXTERNAL SOURCES OF NOISE
221 WALL FINISHES
The walls fall into two categories the interior walls and the exterior walls The interiors walls
are designed with hollow sand-crete blocks with a layer of mortar plastering which is finished
with coating of light coloured cream emulsion paints The acoustic property of sand-crete blocks
rendered with cement plaster has a pretty low absorption co-efficient
The exterior walls are also constructed with sand-crete blocks with a layer of mortar screed and
they are finished with textcoat paints which are also light coloured cream The roughness the
pg 3
PLATE 2
surface improves its acoustic quality because Rough walls tend to diffuse sound reflecting it in
a variety of directions Hence very little sound can be absorbed from out noise sources and
transmitted into the building and coupled with the fact that itrsquos almost a secluded area with little
movement around without a real purpose
222 FLOOR FINISHES
The floors of the spaces in the buildings are finished with deep polished terrazzo floor finish
This is quite poor as an acoustic material since terrazzo has a very low absorption co-efficient
002 at 1000Hz and its smooth nature reflects the sound
undesirably
But with this in mind a correction measure had
already been taking by laying of sound absorbing
material Ie rug and an underlay foam which actually
helps in reducing the echoes or reverberations of
sound whenever the room is put to use
223 CEILING FINISHES
Due to the use at which the room is put to the ceiling was finished with wooden plywood of
600x600mm and a little part finished with concrete slabs with a layer of mortar screed Wood
was used as the ceiling finish because of its acoustics capabilities wood produces sound by
direct striking and can amplify or absorb sound waves
originating from other bodies For these reasons itrsquos a
unique material for musical instruments and other
acoustics applications like that itrsquos used for at the old
senate chamber because when sound waves of extrinsic
origin strike wood they partly absorbed and partly
pg 4
PLATE 4
PLATE 3
reflected and the wood is set in vibration
NOTE normally wood absorbs a very small portion of acoustic energy (3-5percent) but
special constructions incorporating empty spaces and porous insulation boards can
increase absorption to as high as 90percent
224 FENESTRATIONS
The amount of openings in a space is referred to as Fenestration It is a critical feature in
acoustic considerations in buildings The shape type and size of the fenestrations are parameters
that shouldnrsquot be undermined in takingnoting architectural acoustics The windows in the old
senate chamber are made from glass and they are fixed type The windows are of 300mm height
but span the whole of the room at the bottom and top side of the room with the only movable
window been the windows at the podium of the chamber which are often locked as well They
are framed with aluminum mullions The two doors in the chamber are also made of tempered
glass of between 8mm-10mm thick glass framed with aluminum mullions and are all double leaf
swing doors of 900 x 2100mm per leaf
The windows are predominantly used for lighting but not
for ventilation purposes as the major ventilation in the chamber
are artificial hence they are always left locked The closed
window then disallows and reduces external noise to
Impinge the internal spaces
225 FURNITURE
The furniture in the spaces under consideration goes with the use The basic furniture types are
the plywood drawing boards there are also wooded chairs with cloth cladding and heavy timber
deskscabinets Wood generally is a good absorber of sound but that is not enough to improve the
acoustics of the room to an appreciable level also The acoustics of the chamber may be very
pg 5
PLATE 5
different when it is full from when it is empty empty seats reflect sound whereas an audience
absorbs sound
30 VIEW OF THE SEATING AND AUDIO VISUAL ARRANGEMENT IN THE
CHAMBER
pg 6
PLATE 6
stage areadirect sound
reverberated sound
Absorbed sound
seating area
Reverberated sound
PLATE 7 The interior view elevation
31 SOURCES OF INTERNAL AND EXTERNAL NOISE IN THE OLD SENATE
CHAMBER
In the process of analyzing the acoustics properties of the old senate chamber we analyze the
noise source both from the internal and external sources the noise from external areas ndashwhich is
commonly referred to as outdoor noise And noise from the internal spaces and from the
interactions- which are also referred to as indoor noise
These two categories would be considered in detail with the senate building as study
32 SOURCES OF OUTDOOR NOISE
1048707 VEHICULAR TRAFFIC Vehicles generate noise as they are driven in and out of the senate
area most especially close to the senate chamber itself at the lower floor Noise from the roads
opposite the chamber going to the auditorium possess several challenges most especially when a
program is been held at the auditorium the up and down movement of cars also increase the
noise in the environment But due to the low fenestration of the chamber it has a very
minimal effect on the interior as background noise
1048707 PEDESTRIAN AND CIRCULATION IN WALKWAYS since the senate building itself is
located in the busy bank area of the school pedestrian movement from different sources causes
much noise to the chamber This is also a disadvantage to the acoustic of the room most
especially because the senate chamber is located close to this pedestrian route Chatting shouting
and general sounds are part of the activities that produce the noise that is disseminated from the
pedestrian access roads also in the senate circulation area around the chamber pedestrian
pg 7
movement though restricted in a way still affects the acoustics of the room But again reduction
in the openings aids the room by reducing the noise from outside to its barest minimum
1048707 MECHANICAL NOISE FROM FUTA FM ELECTRICITY GENERATING PLANT
AND AC
The Futa FM generator is located near the old senate chamber and power outage during the day
causes the generator to be turned on hence noxious sounds are disseminated from this massive
plant due to ageing
Secondly the noises from the window unit AC around the chamber in the senate building also
add to the noise level
32 SOURCES OF INDOOR NOISE
bull Audience noise this is the noise that is usually disseminated from the audience in the room ie
the chamber users (students when invited for panel or other matters and lecturers both teaching
and non-teaching depending on the purpose of the use) this problem of audience is
fundamentally inevitable in acoustics as the users of the building must make sounds of different
sorts which could be as a result of talking coughing ringing of phones etc Though this effect is
at the minimum due to the materials used in the finishes of the room that absorb those sound
bull Mechanical noise
These are noise from the mechanical appliances in the room noise from the split unit ac and the
ceiling fans which is almost a constant source of noise in the room due to the fact that there is
pg 8
little or no natural ventilation in the room the only openings in the room are for lighting and not
ventilation which has both negative and positive impact on the room This are the two major
source of noise in the old senate chamber all other sources that could be found or associated
with the room has been taking care of with use of rugs wooden furniture foam
underlay wooden ceiling etc
40 ASSESSMENT OF THE ACOUSTIC CHARACTERISTICS OF THE OLD SENATE
CHAMBER - EFFECTS OF THE INTERNAL AND EXTERNAL SOURCES OF NOISE
The acoustics characteristics of the space can be described under the following headings
The Background noise (external sources)
Reverberation and Echoes (Internal sources)
THE BACKGROUND NOISE
The Background noise that is transmitted into the interior spaces of the building has been
shielded and reduced to its barest minimum to a very good extent with the location of the
chamber in a less traffic area of the senate on the first floor the use of thick glass fixed windows
which has reduced the noise from the background leaving just the door as the only major
opening in the room All other sources of background noise like generators window unit ac
pedestrian movement etc affects majorly only when the doors are opened which is on a
minimal occasion
pg 9
REVERBERATION AND ECHOES
Reverberation is the persistence of sound in an enclosed space due to repeated reflection or
scattering after the sound source has stopped
Echo is a reflection of sound in a large room It is a distinct repetition of the original sound
though it is fainter because not all original sound is reflected
The design of the interiors space in the chamber is such that each person has a direct line of
auditory perception because of the way the room is constructed with stepped levels of seats
Although the walls surfaces are smooth and aids reflection the reverberation time is such that
speech is intelligent in the building
The materials used in the interior space are acoustics inclined For example the floor was ruged
and thick foam underlay layed under the rug which as a good sound absorbing ability the
ceiling materials for the sitting area are made of sound absorbing materials (wood) thus reducing
reflection However it is of note that echoes arenrsquot usually experienced in the room even though
the wall is of a smooth emulsion material
Note Reverberation is less when the room is put to use ie contains people because their bodies
absorb the sand waves and it also reduces the intensity of the sound but due to the cascading of
the seats it will not a be a problem because each person seated in row s will be able to hear well
without obstruction
pg 10
50 PROPOSAL FOR IMPROVING THE ACOUSTICS OF THE OLD SENATE
CHAMBER
This proposal is going to address this issue through two channels which would be methods of
reducing internal noise and methods of reducing external noise
51 REDUCTION OF INTERNAL NOISE
Basically the major acoustics materials that are meant to be put in place are already there ie the
floor material the ceiling etc but few things still needs to be checked and it listed as follows
1048707 Use of textured walls making the walls in the room a rough wall will help to diffuse the
sound coming from the speaker because the direct sound is disseminated around the room when
it impacts on these wall surfaces Hence a sensation of an ominous sound is heard A smooth
surface converges the sound to a point thereby distorting it Materials like cork particle board
felt wall carpets or wall papers help diminish internal noise in the space
1048707 Ceiling Finishes itrsquos important to cover the concrete part of the room with the use of the
suspended type of ceiling covering to create a void between the concrete slab and the space
below White perforated gypsum acoustic suspended ceiling boards could be used as a finish or
wood as used in other parts of the ceiling
1048707Installation of good AC unit with good silencer to replace the ceiling fans
The installation of more air-conditioning unit will eliminate the ceiling fan which reduces the
sound produced by the ceiling fan However these AC units should be sound proof to avoid
pg 11
generating noise and the already installed could be changed or serviced when necessary to
eliminate sound it might produce due to servicing
1048707full upholstery of seats Some seats have been replaced by a plastic chairs due to maybe
dilapidation of the former ones but they need to replace them back with full upholstery seats
52 REDUCTION OF EXTERNAL NOISE
Itrsquos deduced after considering the acoustics correction steps the major ways of rectifying the
external noise has already been put in place which is the insulation of the space the only thing
needed is that of the maintenance of the acoustics materials (thick glass n textured paints where
necessary) in case of damage and the use of textured wall like that of the interior
60 CONCLUSION
During the course of this research we can deduce that the treatment of the interior compartment
of any building most especially a room that is to be used as an auditorium is a very sensitive one
and should be monitored from start to finish ie from construction level to finish level Acoustics
studying of the senate chamber as helped in various ways and it will definitely have effects on
our careers both now and in the future Its successes and failure in buildings noise sources and
control and ways of apply it during design are well understood now to a better extent
pg 12
70 REFERENCES
Prof Olu Ola Ogunsote Acoustics and noise control lecture notes
Diamant RME (1986) Thermal and acoustic insulation University Press Cambridge
httpwwwsdngnetcom
pg 13
surface improves its acoustic quality because Rough walls tend to diffuse sound reflecting it in
a variety of directions Hence very little sound can be absorbed from out noise sources and
transmitted into the building and coupled with the fact that itrsquos almost a secluded area with little
movement around without a real purpose
222 FLOOR FINISHES
The floors of the spaces in the buildings are finished with deep polished terrazzo floor finish
This is quite poor as an acoustic material since terrazzo has a very low absorption co-efficient
002 at 1000Hz and its smooth nature reflects the sound
undesirably
But with this in mind a correction measure had
already been taking by laying of sound absorbing
material Ie rug and an underlay foam which actually
helps in reducing the echoes or reverberations of
sound whenever the room is put to use
223 CEILING FINISHES
Due to the use at which the room is put to the ceiling was finished with wooden plywood of
600x600mm and a little part finished with concrete slabs with a layer of mortar screed Wood
was used as the ceiling finish because of its acoustics capabilities wood produces sound by
direct striking and can amplify or absorb sound waves
originating from other bodies For these reasons itrsquos a
unique material for musical instruments and other
acoustics applications like that itrsquos used for at the old
senate chamber because when sound waves of extrinsic
origin strike wood they partly absorbed and partly
pg 4
PLATE 4
PLATE 3
reflected and the wood is set in vibration
NOTE normally wood absorbs a very small portion of acoustic energy (3-5percent) but
special constructions incorporating empty spaces and porous insulation boards can
increase absorption to as high as 90percent
224 FENESTRATIONS
The amount of openings in a space is referred to as Fenestration It is a critical feature in
acoustic considerations in buildings The shape type and size of the fenestrations are parameters
that shouldnrsquot be undermined in takingnoting architectural acoustics The windows in the old
senate chamber are made from glass and they are fixed type The windows are of 300mm height
but span the whole of the room at the bottom and top side of the room with the only movable
window been the windows at the podium of the chamber which are often locked as well They
are framed with aluminum mullions The two doors in the chamber are also made of tempered
glass of between 8mm-10mm thick glass framed with aluminum mullions and are all double leaf
swing doors of 900 x 2100mm per leaf
The windows are predominantly used for lighting but not
for ventilation purposes as the major ventilation in the chamber
are artificial hence they are always left locked The closed
window then disallows and reduces external noise to
Impinge the internal spaces
225 FURNITURE
The furniture in the spaces under consideration goes with the use The basic furniture types are
the plywood drawing boards there are also wooded chairs with cloth cladding and heavy timber
deskscabinets Wood generally is a good absorber of sound but that is not enough to improve the
acoustics of the room to an appreciable level also The acoustics of the chamber may be very
pg 5
PLATE 5
different when it is full from when it is empty empty seats reflect sound whereas an audience
absorbs sound
30 VIEW OF THE SEATING AND AUDIO VISUAL ARRANGEMENT IN THE
CHAMBER
pg 6
PLATE 6
stage areadirect sound
reverberated sound
Absorbed sound
seating area
Reverberated sound
PLATE 7 The interior view elevation
31 SOURCES OF INTERNAL AND EXTERNAL NOISE IN THE OLD SENATE
CHAMBER
In the process of analyzing the acoustics properties of the old senate chamber we analyze the
noise source both from the internal and external sources the noise from external areas ndashwhich is
commonly referred to as outdoor noise And noise from the internal spaces and from the
interactions- which are also referred to as indoor noise
These two categories would be considered in detail with the senate building as study
32 SOURCES OF OUTDOOR NOISE
1048707 VEHICULAR TRAFFIC Vehicles generate noise as they are driven in and out of the senate
area most especially close to the senate chamber itself at the lower floor Noise from the roads
opposite the chamber going to the auditorium possess several challenges most especially when a
program is been held at the auditorium the up and down movement of cars also increase the
noise in the environment But due to the low fenestration of the chamber it has a very
minimal effect on the interior as background noise
1048707 PEDESTRIAN AND CIRCULATION IN WALKWAYS since the senate building itself is
located in the busy bank area of the school pedestrian movement from different sources causes
much noise to the chamber This is also a disadvantage to the acoustic of the room most
especially because the senate chamber is located close to this pedestrian route Chatting shouting
and general sounds are part of the activities that produce the noise that is disseminated from the
pedestrian access roads also in the senate circulation area around the chamber pedestrian
pg 7
movement though restricted in a way still affects the acoustics of the room But again reduction
in the openings aids the room by reducing the noise from outside to its barest minimum
1048707 MECHANICAL NOISE FROM FUTA FM ELECTRICITY GENERATING PLANT
AND AC
The Futa FM generator is located near the old senate chamber and power outage during the day
causes the generator to be turned on hence noxious sounds are disseminated from this massive
plant due to ageing
Secondly the noises from the window unit AC around the chamber in the senate building also
add to the noise level
32 SOURCES OF INDOOR NOISE
bull Audience noise this is the noise that is usually disseminated from the audience in the room ie
the chamber users (students when invited for panel or other matters and lecturers both teaching
and non-teaching depending on the purpose of the use) this problem of audience is
fundamentally inevitable in acoustics as the users of the building must make sounds of different
sorts which could be as a result of talking coughing ringing of phones etc Though this effect is
at the minimum due to the materials used in the finishes of the room that absorb those sound
bull Mechanical noise
These are noise from the mechanical appliances in the room noise from the split unit ac and the
ceiling fans which is almost a constant source of noise in the room due to the fact that there is
pg 8
little or no natural ventilation in the room the only openings in the room are for lighting and not
ventilation which has both negative and positive impact on the room This are the two major
source of noise in the old senate chamber all other sources that could be found or associated
with the room has been taking care of with use of rugs wooden furniture foam
underlay wooden ceiling etc
40 ASSESSMENT OF THE ACOUSTIC CHARACTERISTICS OF THE OLD SENATE
CHAMBER - EFFECTS OF THE INTERNAL AND EXTERNAL SOURCES OF NOISE
The acoustics characteristics of the space can be described under the following headings
The Background noise (external sources)
Reverberation and Echoes (Internal sources)
THE BACKGROUND NOISE
The Background noise that is transmitted into the interior spaces of the building has been
shielded and reduced to its barest minimum to a very good extent with the location of the
chamber in a less traffic area of the senate on the first floor the use of thick glass fixed windows
which has reduced the noise from the background leaving just the door as the only major
opening in the room All other sources of background noise like generators window unit ac
pedestrian movement etc affects majorly only when the doors are opened which is on a
minimal occasion
pg 9
REVERBERATION AND ECHOES
Reverberation is the persistence of sound in an enclosed space due to repeated reflection or
scattering after the sound source has stopped
Echo is a reflection of sound in a large room It is a distinct repetition of the original sound
though it is fainter because not all original sound is reflected
The design of the interiors space in the chamber is such that each person has a direct line of
auditory perception because of the way the room is constructed with stepped levels of seats
Although the walls surfaces are smooth and aids reflection the reverberation time is such that
speech is intelligent in the building
The materials used in the interior space are acoustics inclined For example the floor was ruged
and thick foam underlay layed under the rug which as a good sound absorbing ability the
ceiling materials for the sitting area are made of sound absorbing materials (wood) thus reducing
reflection However it is of note that echoes arenrsquot usually experienced in the room even though
the wall is of a smooth emulsion material
Note Reverberation is less when the room is put to use ie contains people because their bodies
absorb the sand waves and it also reduces the intensity of the sound but due to the cascading of
the seats it will not a be a problem because each person seated in row s will be able to hear well
without obstruction
pg 10
50 PROPOSAL FOR IMPROVING THE ACOUSTICS OF THE OLD SENATE
CHAMBER
This proposal is going to address this issue through two channels which would be methods of
reducing internal noise and methods of reducing external noise
51 REDUCTION OF INTERNAL NOISE
Basically the major acoustics materials that are meant to be put in place are already there ie the
floor material the ceiling etc but few things still needs to be checked and it listed as follows
1048707 Use of textured walls making the walls in the room a rough wall will help to diffuse the
sound coming from the speaker because the direct sound is disseminated around the room when
it impacts on these wall surfaces Hence a sensation of an ominous sound is heard A smooth
surface converges the sound to a point thereby distorting it Materials like cork particle board
felt wall carpets or wall papers help diminish internal noise in the space
1048707 Ceiling Finishes itrsquos important to cover the concrete part of the room with the use of the
suspended type of ceiling covering to create a void between the concrete slab and the space
below White perforated gypsum acoustic suspended ceiling boards could be used as a finish or
wood as used in other parts of the ceiling
1048707Installation of good AC unit with good silencer to replace the ceiling fans
The installation of more air-conditioning unit will eliminate the ceiling fan which reduces the
sound produced by the ceiling fan However these AC units should be sound proof to avoid
pg 11
generating noise and the already installed could be changed or serviced when necessary to
eliminate sound it might produce due to servicing
1048707full upholstery of seats Some seats have been replaced by a plastic chairs due to maybe
dilapidation of the former ones but they need to replace them back with full upholstery seats
52 REDUCTION OF EXTERNAL NOISE
Itrsquos deduced after considering the acoustics correction steps the major ways of rectifying the
external noise has already been put in place which is the insulation of the space the only thing
needed is that of the maintenance of the acoustics materials (thick glass n textured paints where
necessary) in case of damage and the use of textured wall like that of the interior
60 CONCLUSION
During the course of this research we can deduce that the treatment of the interior compartment
of any building most especially a room that is to be used as an auditorium is a very sensitive one
and should be monitored from start to finish ie from construction level to finish level Acoustics
studying of the senate chamber as helped in various ways and it will definitely have effects on
our careers both now and in the future Its successes and failure in buildings noise sources and
control and ways of apply it during design are well understood now to a better extent
pg 12
70 REFERENCES
Prof Olu Ola Ogunsote Acoustics and noise control lecture notes
Diamant RME (1986) Thermal and acoustic insulation University Press Cambridge
httpwwwsdngnetcom
pg 13
reflected and the wood is set in vibration
NOTE normally wood absorbs a very small portion of acoustic energy (3-5percent) but
special constructions incorporating empty spaces and porous insulation boards can
increase absorption to as high as 90percent
224 FENESTRATIONS
The amount of openings in a space is referred to as Fenestration It is a critical feature in
acoustic considerations in buildings The shape type and size of the fenestrations are parameters
that shouldnrsquot be undermined in takingnoting architectural acoustics The windows in the old
senate chamber are made from glass and they are fixed type The windows are of 300mm height
but span the whole of the room at the bottom and top side of the room with the only movable
window been the windows at the podium of the chamber which are often locked as well They
are framed with aluminum mullions The two doors in the chamber are also made of tempered
glass of between 8mm-10mm thick glass framed with aluminum mullions and are all double leaf
swing doors of 900 x 2100mm per leaf
The windows are predominantly used for lighting but not
for ventilation purposes as the major ventilation in the chamber
are artificial hence they are always left locked The closed
window then disallows and reduces external noise to
Impinge the internal spaces
225 FURNITURE
The furniture in the spaces under consideration goes with the use The basic furniture types are
the plywood drawing boards there are also wooded chairs with cloth cladding and heavy timber
deskscabinets Wood generally is a good absorber of sound but that is not enough to improve the
acoustics of the room to an appreciable level also The acoustics of the chamber may be very
pg 5
PLATE 5
different when it is full from when it is empty empty seats reflect sound whereas an audience
absorbs sound
30 VIEW OF THE SEATING AND AUDIO VISUAL ARRANGEMENT IN THE
CHAMBER
pg 6
PLATE 6
stage areadirect sound
reverberated sound
Absorbed sound
seating area
Reverberated sound
PLATE 7 The interior view elevation
31 SOURCES OF INTERNAL AND EXTERNAL NOISE IN THE OLD SENATE
CHAMBER
In the process of analyzing the acoustics properties of the old senate chamber we analyze the
noise source both from the internal and external sources the noise from external areas ndashwhich is
commonly referred to as outdoor noise And noise from the internal spaces and from the
interactions- which are also referred to as indoor noise
These two categories would be considered in detail with the senate building as study
32 SOURCES OF OUTDOOR NOISE
1048707 VEHICULAR TRAFFIC Vehicles generate noise as they are driven in and out of the senate
area most especially close to the senate chamber itself at the lower floor Noise from the roads
opposite the chamber going to the auditorium possess several challenges most especially when a
program is been held at the auditorium the up and down movement of cars also increase the
noise in the environment But due to the low fenestration of the chamber it has a very
minimal effect on the interior as background noise
1048707 PEDESTRIAN AND CIRCULATION IN WALKWAYS since the senate building itself is
located in the busy bank area of the school pedestrian movement from different sources causes
much noise to the chamber This is also a disadvantage to the acoustic of the room most
especially because the senate chamber is located close to this pedestrian route Chatting shouting
and general sounds are part of the activities that produce the noise that is disseminated from the
pedestrian access roads also in the senate circulation area around the chamber pedestrian
pg 7
movement though restricted in a way still affects the acoustics of the room But again reduction
in the openings aids the room by reducing the noise from outside to its barest minimum
1048707 MECHANICAL NOISE FROM FUTA FM ELECTRICITY GENERATING PLANT
AND AC
The Futa FM generator is located near the old senate chamber and power outage during the day
causes the generator to be turned on hence noxious sounds are disseminated from this massive
plant due to ageing
Secondly the noises from the window unit AC around the chamber in the senate building also
add to the noise level
32 SOURCES OF INDOOR NOISE
bull Audience noise this is the noise that is usually disseminated from the audience in the room ie
the chamber users (students when invited for panel or other matters and lecturers both teaching
and non-teaching depending on the purpose of the use) this problem of audience is
fundamentally inevitable in acoustics as the users of the building must make sounds of different
sorts which could be as a result of talking coughing ringing of phones etc Though this effect is
at the minimum due to the materials used in the finishes of the room that absorb those sound
bull Mechanical noise
These are noise from the mechanical appliances in the room noise from the split unit ac and the
ceiling fans which is almost a constant source of noise in the room due to the fact that there is
pg 8
little or no natural ventilation in the room the only openings in the room are for lighting and not
ventilation which has both negative and positive impact on the room This are the two major
source of noise in the old senate chamber all other sources that could be found or associated
with the room has been taking care of with use of rugs wooden furniture foam
underlay wooden ceiling etc
40 ASSESSMENT OF THE ACOUSTIC CHARACTERISTICS OF THE OLD SENATE
CHAMBER - EFFECTS OF THE INTERNAL AND EXTERNAL SOURCES OF NOISE
The acoustics characteristics of the space can be described under the following headings
The Background noise (external sources)
Reverberation and Echoes (Internal sources)
THE BACKGROUND NOISE
The Background noise that is transmitted into the interior spaces of the building has been
shielded and reduced to its barest minimum to a very good extent with the location of the
chamber in a less traffic area of the senate on the first floor the use of thick glass fixed windows
which has reduced the noise from the background leaving just the door as the only major
opening in the room All other sources of background noise like generators window unit ac
pedestrian movement etc affects majorly only when the doors are opened which is on a
minimal occasion
pg 9
REVERBERATION AND ECHOES
Reverberation is the persistence of sound in an enclosed space due to repeated reflection or
scattering after the sound source has stopped
Echo is a reflection of sound in a large room It is a distinct repetition of the original sound
though it is fainter because not all original sound is reflected
The design of the interiors space in the chamber is such that each person has a direct line of
auditory perception because of the way the room is constructed with stepped levels of seats
Although the walls surfaces are smooth and aids reflection the reverberation time is such that
speech is intelligent in the building
The materials used in the interior space are acoustics inclined For example the floor was ruged
and thick foam underlay layed under the rug which as a good sound absorbing ability the
ceiling materials for the sitting area are made of sound absorbing materials (wood) thus reducing
reflection However it is of note that echoes arenrsquot usually experienced in the room even though
the wall is of a smooth emulsion material
Note Reverberation is less when the room is put to use ie contains people because their bodies
absorb the sand waves and it also reduces the intensity of the sound but due to the cascading of
the seats it will not a be a problem because each person seated in row s will be able to hear well
without obstruction
pg 10
50 PROPOSAL FOR IMPROVING THE ACOUSTICS OF THE OLD SENATE
CHAMBER
This proposal is going to address this issue through two channels which would be methods of
reducing internal noise and methods of reducing external noise
51 REDUCTION OF INTERNAL NOISE
Basically the major acoustics materials that are meant to be put in place are already there ie the
floor material the ceiling etc but few things still needs to be checked and it listed as follows
1048707 Use of textured walls making the walls in the room a rough wall will help to diffuse the
sound coming from the speaker because the direct sound is disseminated around the room when
it impacts on these wall surfaces Hence a sensation of an ominous sound is heard A smooth
surface converges the sound to a point thereby distorting it Materials like cork particle board
felt wall carpets or wall papers help diminish internal noise in the space
1048707 Ceiling Finishes itrsquos important to cover the concrete part of the room with the use of the
suspended type of ceiling covering to create a void between the concrete slab and the space
below White perforated gypsum acoustic suspended ceiling boards could be used as a finish or
wood as used in other parts of the ceiling
1048707Installation of good AC unit with good silencer to replace the ceiling fans
The installation of more air-conditioning unit will eliminate the ceiling fan which reduces the
sound produced by the ceiling fan However these AC units should be sound proof to avoid
pg 11
generating noise and the already installed could be changed or serviced when necessary to
eliminate sound it might produce due to servicing
1048707full upholstery of seats Some seats have been replaced by a plastic chairs due to maybe
dilapidation of the former ones but they need to replace them back with full upholstery seats
52 REDUCTION OF EXTERNAL NOISE
Itrsquos deduced after considering the acoustics correction steps the major ways of rectifying the
external noise has already been put in place which is the insulation of the space the only thing
needed is that of the maintenance of the acoustics materials (thick glass n textured paints where
necessary) in case of damage and the use of textured wall like that of the interior
60 CONCLUSION
During the course of this research we can deduce that the treatment of the interior compartment
of any building most especially a room that is to be used as an auditorium is a very sensitive one
and should be monitored from start to finish ie from construction level to finish level Acoustics
studying of the senate chamber as helped in various ways and it will definitely have effects on
our careers both now and in the future Its successes and failure in buildings noise sources and
control and ways of apply it during design are well understood now to a better extent
pg 12
70 REFERENCES
Prof Olu Ola Ogunsote Acoustics and noise control lecture notes
Diamant RME (1986) Thermal and acoustic insulation University Press Cambridge
httpwwwsdngnetcom
pg 13
different when it is full from when it is empty empty seats reflect sound whereas an audience
absorbs sound
30 VIEW OF THE SEATING AND AUDIO VISUAL ARRANGEMENT IN THE
CHAMBER
pg 6
PLATE 6
stage areadirect sound
reverberated sound
Absorbed sound
seating area
Reverberated sound
PLATE 7 The interior view elevation
31 SOURCES OF INTERNAL AND EXTERNAL NOISE IN THE OLD SENATE
CHAMBER
In the process of analyzing the acoustics properties of the old senate chamber we analyze the
noise source both from the internal and external sources the noise from external areas ndashwhich is
commonly referred to as outdoor noise And noise from the internal spaces and from the
interactions- which are also referred to as indoor noise
These two categories would be considered in detail with the senate building as study
32 SOURCES OF OUTDOOR NOISE
1048707 VEHICULAR TRAFFIC Vehicles generate noise as they are driven in and out of the senate
area most especially close to the senate chamber itself at the lower floor Noise from the roads
opposite the chamber going to the auditorium possess several challenges most especially when a
program is been held at the auditorium the up and down movement of cars also increase the
noise in the environment But due to the low fenestration of the chamber it has a very
minimal effect on the interior as background noise
1048707 PEDESTRIAN AND CIRCULATION IN WALKWAYS since the senate building itself is
located in the busy bank area of the school pedestrian movement from different sources causes
much noise to the chamber This is also a disadvantage to the acoustic of the room most
especially because the senate chamber is located close to this pedestrian route Chatting shouting
and general sounds are part of the activities that produce the noise that is disseminated from the
pedestrian access roads also in the senate circulation area around the chamber pedestrian
pg 7
movement though restricted in a way still affects the acoustics of the room But again reduction
in the openings aids the room by reducing the noise from outside to its barest minimum
1048707 MECHANICAL NOISE FROM FUTA FM ELECTRICITY GENERATING PLANT
AND AC
The Futa FM generator is located near the old senate chamber and power outage during the day
causes the generator to be turned on hence noxious sounds are disseminated from this massive
plant due to ageing
Secondly the noises from the window unit AC around the chamber in the senate building also
add to the noise level
32 SOURCES OF INDOOR NOISE
bull Audience noise this is the noise that is usually disseminated from the audience in the room ie
the chamber users (students when invited for panel or other matters and lecturers both teaching
and non-teaching depending on the purpose of the use) this problem of audience is
fundamentally inevitable in acoustics as the users of the building must make sounds of different
sorts which could be as a result of talking coughing ringing of phones etc Though this effect is
at the minimum due to the materials used in the finishes of the room that absorb those sound
bull Mechanical noise
These are noise from the mechanical appliances in the room noise from the split unit ac and the
ceiling fans which is almost a constant source of noise in the room due to the fact that there is
pg 8
little or no natural ventilation in the room the only openings in the room are for lighting and not
ventilation which has both negative and positive impact on the room This are the two major
source of noise in the old senate chamber all other sources that could be found or associated
with the room has been taking care of with use of rugs wooden furniture foam
underlay wooden ceiling etc
40 ASSESSMENT OF THE ACOUSTIC CHARACTERISTICS OF THE OLD SENATE
CHAMBER - EFFECTS OF THE INTERNAL AND EXTERNAL SOURCES OF NOISE
The acoustics characteristics of the space can be described under the following headings
The Background noise (external sources)
Reverberation and Echoes (Internal sources)
THE BACKGROUND NOISE
The Background noise that is transmitted into the interior spaces of the building has been
shielded and reduced to its barest minimum to a very good extent with the location of the
chamber in a less traffic area of the senate on the first floor the use of thick glass fixed windows
which has reduced the noise from the background leaving just the door as the only major
opening in the room All other sources of background noise like generators window unit ac
pedestrian movement etc affects majorly only when the doors are opened which is on a
minimal occasion
pg 9
REVERBERATION AND ECHOES
Reverberation is the persistence of sound in an enclosed space due to repeated reflection or
scattering after the sound source has stopped
Echo is a reflection of sound in a large room It is a distinct repetition of the original sound
though it is fainter because not all original sound is reflected
The design of the interiors space in the chamber is such that each person has a direct line of
auditory perception because of the way the room is constructed with stepped levels of seats
Although the walls surfaces are smooth and aids reflection the reverberation time is such that
speech is intelligent in the building
The materials used in the interior space are acoustics inclined For example the floor was ruged
and thick foam underlay layed under the rug which as a good sound absorbing ability the
ceiling materials for the sitting area are made of sound absorbing materials (wood) thus reducing
reflection However it is of note that echoes arenrsquot usually experienced in the room even though
the wall is of a smooth emulsion material
Note Reverberation is less when the room is put to use ie contains people because their bodies
absorb the sand waves and it also reduces the intensity of the sound but due to the cascading of
the seats it will not a be a problem because each person seated in row s will be able to hear well
without obstruction
pg 10
50 PROPOSAL FOR IMPROVING THE ACOUSTICS OF THE OLD SENATE
CHAMBER
This proposal is going to address this issue through two channels which would be methods of
reducing internal noise and methods of reducing external noise
51 REDUCTION OF INTERNAL NOISE
Basically the major acoustics materials that are meant to be put in place are already there ie the
floor material the ceiling etc but few things still needs to be checked and it listed as follows
1048707 Use of textured walls making the walls in the room a rough wall will help to diffuse the
sound coming from the speaker because the direct sound is disseminated around the room when
it impacts on these wall surfaces Hence a sensation of an ominous sound is heard A smooth
surface converges the sound to a point thereby distorting it Materials like cork particle board
felt wall carpets or wall papers help diminish internal noise in the space
1048707 Ceiling Finishes itrsquos important to cover the concrete part of the room with the use of the
suspended type of ceiling covering to create a void between the concrete slab and the space
below White perforated gypsum acoustic suspended ceiling boards could be used as a finish or
wood as used in other parts of the ceiling
1048707Installation of good AC unit with good silencer to replace the ceiling fans
The installation of more air-conditioning unit will eliminate the ceiling fan which reduces the
sound produced by the ceiling fan However these AC units should be sound proof to avoid
pg 11
generating noise and the already installed could be changed or serviced when necessary to
eliminate sound it might produce due to servicing
1048707full upholstery of seats Some seats have been replaced by a plastic chairs due to maybe
dilapidation of the former ones but they need to replace them back with full upholstery seats
52 REDUCTION OF EXTERNAL NOISE
Itrsquos deduced after considering the acoustics correction steps the major ways of rectifying the
external noise has already been put in place which is the insulation of the space the only thing
needed is that of the maintenance of the acoustics materials (thick glass n textured paints where
necessary) in case of damage and the use of textured wall like that of the interior
60 CONCLUSION
During the course of this research we can deduce that the treatment of the interior compartment
of any building most especially a room that is to be used as an auditorium is a very sensitive one
and should be monitored from start to finish ie from construction level to finish level Acoustics
studying of the senate chamber as helped in various ways and it will definitely have effects on
our careers both now and in the future Its successes and failure in buildings noise sources and
control and ways of apply it during design are well understood now to a better extent
pg 12
70 REFERENCES
Prof Olu Ola Ogunsote Acoustics and noise control lecture notes
Diamant RME (1986) Thermal and acoustic insulation University Press Cambridge
httpwwwsdngnetcom
pg 13
31 SOURCES OF INTERNAL AND EXTERNAL NOISE IN THE OLD SENATE
CHAMBER
In the process of analyzing the acoustics properties of the old senate chamber we analyze the
noise source both from the internal and external sources the noise from external areas ndashwhich is
commonly referred to as outdoor noise And noise from the internal spaces and from the
interactions- which are also referred to as indoor noise
These two categories would be considered in detail with the senate building as study
32 SOURCES OF OUTDOOR NOISE
1048707 VEHICULAR TRAFFIC Vehicles generate noise as they are driven in and out of the senate
area most especially close to the senate chamber itself at the lower floor Noise from the roads
opposite the chamber going to the auditorium possess several challenges most especially when a
program is been held at the auditorium the up and down movement of cars also increase the
noise in the environment But due to the low fenestration of the chamber it has a very
minimal effect on the interior as background noise
1048707 PEDESTRIAN AND CIRCULATION IN WALKWAYS since the senate building itself is
located in the busy bank area of the school pedestrian movement from different sources causes
much noise to the chamber This is also a disadvantage to the acoustic of the room most
especially because the senate chamber is located close to this pedestrian route Chatting shouting
and general sounds are part of the activities that produce the noise that is disseminated from the
pedestrian access roads also in the senate circulation area around the chamber pedestrian
pg 7
movement though restricted in a way still affects the acoustics of the room But again reduction
in the openings aids the room by reducing the noise from outside to its barest minimum
1048707 MECHANICAL NOISE FROM FUTA FM ELECTRICITY GENERATING PLANT
AND AC
The Futa FM generator is located near the old senate chamber and power outage during the day
causes the generator to be turned on hence noxious sounds are disseminated from this massive
plant due to ageing
Secondly the noises from the window unit AC around the chamber in the senate building also
add to the noise level
32 SOURCES OF INDOOR NOISE
bull Audience noise this is the noise that is usually disseminated from the audience in the room ie
the chamber users (students when invited for panel or other matters and lecturers both teaching
and non-teaching depending on the purpose of the use) this problem of audience is
fundamentally inevitable in acoustics as the users of the building must make sounds of different
sorts which could be as a result of talking coughing ringing of phones etc Though this effect is
at the minimum due to the materials used in the finishes of the room that absorb those sound
bull Mechanical noise
These are noise from the mechanical appliances in the room noise from the split unit ac and the
ceiling fans which is almost a constant source of noise in the room due to the fact that there is
pg 8
little or no natural ventilation in the room the only openings in the room are for lighting and not
ventilation which has both negative and positive impact on the room This are the two major
source of noise in the old senate chamber all other sources that could be found or associated
with the room has been taking care of with use of rugs wooden furniture foam
underlay wooden ceiling etc
40 ASSESSMENT OF THE ACOUSTIC CHARACTERISTICS OF THE OLD SENATE
CHAMBER - EFFECTS OF THE INTERNAL AND EXTERNAL SOURCES OF NOISE
The acoustics characteristics of the space can be described under the following headings
The Background noise (external sources)
Reverberation and Echoes (Internal sources)
THE BACKGROUND NOISE
The Background noise that is transmitted into the interior spaces of the building has been
shielded and reduced to its barest minimum to a very good extent with the location of the
chamber in a less traffic area of the senate on the first floor the use of thick glass fixed windows
which has reduced the noise from the background leaving just the door as the only major
opening in the room All other sources of background noise like generators window unit ac
pedestrian movement etc affects majorly only when the doors are opened which is on a
minimal occasion
pg 9
REVERBERATION AND ECHOES
Reverberation is the persistence of sound in an enclosed space due to repeated reflection or
scattering after the sound source has stopped
Echo is a reflection of sound in a large room It is a distinct repetition of the original sound
though it is fainter because not all original sound is reflected
The design of the interiors space in the chamber is such that each person has a direct line of
auditory perception because of the way the room is constructed with stepped levels of seats
Although the walls surfaces are smooth and aids reflection the reverberation time is such that
speech is intelligent in the building
The materials used in the interior space are acoustics inclined For example the floor was ruged
and thick foam underlay layed under the rug which as a good sound absorbing ability the
ceiling materials for the sitting area are made of sound absorbing materials (wood) thus reducing
reflection However it is of note that echoes arenrsquot usually experienced in the room even though
the wall is of a smooth emulsion material
Note Reverberation is less when the room is put to use ie contains people because their bodies
absorb the sand waves and it also reduces the intensity of the sound but due to the cascading of
the seats it will not a be a problem because each person seated in row s will be able to hear well
without obstruction
pg 10
50 PROPOSAL FOR IMPROVING THE ACOUSTICS OF THE OLD SENATE
CHAMBER
This proposal is going to address this issue through two channels which would be methods of
reducing internal noise and methods of reducing external noise
51 REDUCTION OF INTERNAL NOISE
Basically the major acoustics materials that are meant to be put in place are already there ie the
floor material the ceiling etc but few things still needs to be checked and it listed as follows
1048707 Use of textured walls making the walls in the room a rough wall will help to diffuse the
sound coming from the speaker because the direct sound is disseminated around the room when
it impacts on these wall surfaces Hence a sensation of an ominous sound is heard A smooth
surface converges the sound to a point thereby distorting it Materials like cork particle board
felt wall carpets or wall papers help diminish internal noise in the space
1048707 Ceiling Finishes itrsquos important to cover the concrete part of the room with the use of the
suspended type of ceiling covering to create a void between the concrete slab and the space
below White perforated gypsum acoustic suspended ceiling boards could be used as a finish or
wood as used in other parts of the ceiling
1048707Installation of good AC unit with good silencer to replace the ceiling fans
The installation of more air-conditioning unit will eliminate the ceiling fan which reduces the
sound produced by the ceiling fan However these AC units should be sound proof to avoid
pg 11
generating noise and the already installed could be changed or serviced when necessary to
eliminate sound it might produce due to servicing
1048707full upholstery of seats Some seats have been replaced by a plastic chairs due to maybe
dilapidation of the former ones but they need to replace them back with full upholstery seats
52 REDUCTION OF EXTERNAL NOISE
Itrsquos deduced after considering the acoustics correction steps the major ways of rectifying the
external noise has already been put in place which is the insulation of the space the only thing
needed is that of the maintenance of the acoustics materials (thick glass n textured paints where
necessary) in case of damage and the use of textured wall like that of the interior
60 CONCLUSION
During the course of this research we can deduce that the treatment of the interior compartment
of any building most especially a room that is to be used as an auditorium is a very sensitive one
and should be monitored from start to finish ie from construction level to finish level Acoustics
studying of the senate chamber as helped in various ways and it will definitely have effects on
our careers both now and in the future Its successes and failure in buildings noise sources and
control and ways of apply it during design are well understood now to a better extent
pg 12
70 REFERENCES
Prof Olu Ola Ogunsote Acoustics and noise control lecture notes
Diamant RME (1986) Thermal and acoustic insulation University Press Cambridge
httpwwwsdngnetcom
pg 13
movement though restricted in a way still affects the acoustics of the room But again reduction
in the openings aids the room by reducing the noise from outside to its barest minimum
1048707 MECHANICAL NOISE FROM FUTA FM ELECTRICITY GENERATING PLANT
AND AC
The Futa FM generator is located near the old senate chamber and power outage during the day
causes the generator to be turned on hence noxious sounds are disseminated from this massive
plant due to ageing
Secondly the noises from the window unit AC around the chamber in the senate building also
add to the noise level
32 SOURCES OF INDOOR NOISE
bull Audience noise this is the noise that is usually disseminated from the audience in the room ie
the chamber users (students when invited for panel or other matters and lecturers both teaching
and non-teaching depending on the purpose of the use) this problem of audience is
fundamentally inevitable in acoustics as the users of the building must make sounds of different
sorts which could be as a result of talking coughing ringing of phones etc Though this effect is
at the minimum due to the materials used in the finishes of the room that absorb those sound
bull Mechanical noise
These are noise from the mechanical appliances in the room noise from the split unit ac and the
ceiling fans which is almost a constant source of noise in the room due to the fact that there is
pg 8
little or no natural ventilation in the room the only openings in the room are for lighting and not
ventilation which has both negative and positive impact on the room This are the two major
source of noise in the old senate chamber all other sources that could be found or associated
with the room has been taking care of with use of rugs wooden furniture foam
underlay wooden ceiling etc
40 ASSESSMENT OF THE ACOUSTIC CHARACTERISTICS OF THE OLD SENATE
CHAMBER - EFFECTS OF THE INTERNAL AND EXTERNAL SOURCES OF NOISE
The acoustics characteristics of the space can be described under the following headings
The Background noise (external sources)
Reverberation and Echoes (Internal sources)
THE BACKGROUND NOISE
The Background noise that is transmitted into the interior spaces of the building has been
shielded and reduced to its barest minimum to a very good extent with the location of the
chamber in a less traffic area of the senate on the first floor the use of thick glass fixed windows
which has reduced the noise from the background leaving just the door as the only major
opening in the room All other sources of background noise like generators window unit ac
pedestrian movement etc affects majorly only when the doors are opened which is on a
minimal occasion
pg 9
REVERBERATION AND ECHOES
Reverberation is the persistence of sound in an enclosed space due to repeated reflection or
scattering after the sound source has stopped
Echo is a reflection of sound in a large room It is a distinct repetition of the original sound
though it is fainter because not all original sound is reflected
The design of the interiors space in the chamber is such that each person has a direct line of
auditory perception because of the way the room is constructed with stepped levels of seats
Although the walls surfaces are smooth and aids reflection the reverberation time is such that
speech is intelligent in the building
The materials used in the interior space are acoustics inclined For example the floor was ruged
and thick foam underlay layed under the rug which as a good sound absorbing ability the
ceiling materials for the sitting area are made of sound absorbing materials (wood) thus reducing
reflection However it is of note that echoes arenrsquot usually experienced in the room even though
the wall is of a smooth emulsion material
Note Reverberation is less when the room is put to use ie contains people because their bodies
absorb the sand waves and it also reduces the intensity of the sound but due to the cascading of
the seats it will not a be a problem because each person seated in row s will be able to hear well
without obstruction
pg 10
50 PROPOSAL FOR IMPROVING THE ACOUSTICS OF THE OLD SENATE
CHAMBER
This proposal is going to address this issue through two channels which would be methods of
reducing internal noise and methods of reducing external noise
51 REDUCTION OF INTERNAL NOISE
Basically the major acoustics materials that are meant to be put in place are already there ie the
floor material the ceiling etc but few things still needs to be checked and it listed as follows
1048707 Use of textured walls making the walls in the room a rough wall will help to diffuse the
sound coming from the speaker because the direct sound is disseminated around the room when
it impacts on these wall surfaces Hence a sensation of an ominous sound is heard A smooth
surface converges the sound to a point thereby distorting it Materials like cork particle board
felt wall carpets or wall papers help diminish internal noise in the space
1048707 Ceiling Finishes itrsquos important to cover the concrete part of the room with the use of the
suspended type of ceiling covering to create a void between the concrete slab and the space
below White perforated gypsum acoustic suspended ceiling boards could be used as a finish or
wood as used in other parts of the ceiling
1048707Installation of good AC unit with good silencer to replace the ceiling fans
The installation of more air-conditioning unit will eliminate the ceiling fan which reduces the
sound produced by the ceiling fan However these AC units should be sound proof to avoid
pg 11
generating noise and the already installed could be changed or serviced when necessary to
eliminate sound it might produce due to servicing
1048707full upholstery of seats Some seats have been replaced by a plastic chairs due to maybe
dilapidation of the former ones but they need to replace them back with full upholstery seats
52 REDUCTION OF EXTERNAL NOISE
Itrsquos deduced after considering the acoustics correction steps the major ways of rectifying the
external noise has already been put in place which is the insulation of the space the only thing
needed is that of the maintenance of the acoustics materials (thick glass n textured paints where
necessary) in case of damage and the use of textured wall like that of the interior
60 CONCLUSION
During the course of this research we can deduce that the treatment of the interior compartment
of any building most especially a room that is to be used as an auditorium is a very sensitive one
and should be monitored from start to finish ie from construction level to finish level Acoustics
studying of the senate chamber as helped in various ways and it will definitely have effects on
our careers both now and in the future Its successes and failure in buildings noise sources and
control and ways of apply it during design are well understood now to a better extent
pg 12
70 REFERENCES
Prof Olu Ola Ogunsote Acoustics and noise control lecture notes
Diamant RME (1986) Thermal and acoustic insulation University Press Cambridge
httpwwwsdngnetcom
pg 13
little or no natural ventilation in the room the only openings in the room are for lighting and not
ventilation which has both negative and positive impact on the room This are the two major
source of noise in the old senate chamber all other sources that could be found or associated
with the room has been taking care of with use of rugs wooden furniture foam
underlay wooden ceiling etc
40 ASSESSMENT OF THE ACOUSTIC CHARACTERISTICS OF THE OLD SENATE
CHAMBER - EFFECTS OF THE INTERNAL AND EXTERNAL SOURCES OF NOISE
The acoustics characteristics of the space can be described under the following headings
The Background noise (external sources)
Reverberation and Echoes (Internal sources)
THE BACKGROUND NOISE
The Background noise that is transmitted into the interior spaces of the building has been
shielded and reduced to its barest minimum to a very good extent with the location of the
chamber in a less traffic area of the senate on the first floor the use of thick glass fixed windows
which has reduced the noise from the background leaving just the door as the only major
opening in the room All other sources of background noise like generators window unit ac
pedestrian movement etc affects majorly only when the doors are opened which is on a
minimal occasion
pg 9
REVERBERATION AND ECHOES
Reverberation is the persistence of sound in an enclosed space due to repeated reflection or
scattering after the sound source has stopped
Echo is a reflection of sound in a large room It is a distinct repetition of the original sound
though it is fainter because not all original sound is reflected
The design of the interiors space in the chamber is such that each person has a direct line of
auditory perception because of the way the room is constructed with stepped levels of seats
Although the walls surfaces are smooth and aids reflection the reverberation time is such that
speech is intelligent in the building
The materials used in the interior space are acoustics inclined For example the floor was ruged
and thick foam underlay layed under the rug which as a good sound absorbing ability the
ceiling materials for the sitting area are made of sound absorbing materials (wood) thus reducing
reflection However it is of note that echoes arenrsquot usually experienced in the room even though
the wall is of a smooth emulsion material
Note Reverberation is less when the room is put to use ie contains people because their bodies
absorb the sand waves and it also reduces the intensity of the sound but due to the cascading of
the seats it will not a be a problem because each person seated in row s will be able to hear well
without obstruction
pg 10
50 PROPOSAL FOR IMPROVING THE ACOUSTICS OF THE OLD SENATE
CHAMBER
This proposal is going to address this issue through two channels which would be methods of
reducing internal noise and methods of reducing external noise
51 REDUCTION OF INTERNAL NOISE
Basically the major acoustics materials that are meant to be put in place are already there ie the
floor material the ceiling etc but few things still needs to be checked and it listed as follows
1048707 Use of textured walls making the walls in the room a rough wall will help to diffuse the
sound coming from the speaker because the direct sound is disseminated around the room when
it impacts on these wall surfaces Hence a sensation of an ominous sound is heard A smooth
surface converges the sound to a point thereby distorting it Materials like cork particle board
felt wall carpets or wall papers help diminish internal noise in the space
1048707 Ceiling Finishes itrsquos important to cover the concrete part of the room with the use of the
suspended type of ceiling covering to create a void between the concrete slab and the space
below White perforated gypsum acoustic suspended ceiling boards could be used as a finish or
wood as used in other parts of the ceiling
1048707Installation of good AC unit with good silencer to replace the ceiling fans
The installation of more air-conditioning unit will eliminate the ceiling fan which reduces the
sound produced by the ceiling fan However these AC units should be sound proof to avoid
pg 11
generating noise and the already installed could be changed or serviced when necessary to
eliminate sound it might produce due to servicing
1048707full upholstery of seats Some seats have been replaced by a plastic chairs due to maybe
dilapidation of the former ones but they need to replace them back with full upholstery seats
52 REDUCTION OF EXTERNAL NOISE
Itrsquos deduced after considering the acoustics correction steps the major ways of rectifying the
external noise has already been put in place which is the insulation of the space the only thing
needed is that of the maintenance of the acoustics materials (thick glass n textured paints where
necessary) in case of damage and the use of textured wall like that of the interior
60 CONCLUSION
During the course of this research we can deduce that the treatment of the interior compartment
of any building most especially a room that is to be used as an auditorium is a very sensitive one
and should be monitored from start to finish ie from construction level to finish level Acoustics
studying of the senate chamber as helped in various ways and it will definitely have effects on
our careers both now and in the future Its successes and failure in buildings noise sources and
control and ways of apply it during design are well understood now to a better extent
pg 12
70 REFERENCES
Prof Olu Ola Ogunsote Acoustics and noise control lecture notes
Diamant RME (1986) Thermal and acoustic insulation University Press Cambridge
httpwwwsdngnetcom
pg 13
REVERBERATION AND ECHOES
Reverberation is the persistence of sound in an enclosed space due to repeated reflection or
scattering after the sound source has stopped
Echo is a reflection of sound in a large room It is a distinct repetition of the original sound
though it is fainter because not all original sound is reflected
The design of the interiors space in the chamber is such that each person has a direct line of
auditory perception because of the way the room is constructed with stepped levels of seats
Although the walls surfaces are smooth and aids reflection the reverberation time is such that
speech is intelligent in the building
The materials used in the interior space are acoustics inclined For example the floor was ruged
and thick foam underlay layed under the rug which as a good sound absorbing ability the
ceiling materials for the sitting area are made of sound absorbing materials (wood) thus reducing
reflection However it is of note that echoes arenrsquot usually experienced in the room even though
the wall is of a smooth emulsion material
Note Reverberation is less when the room is put to use ie contains people because their bodies
absorb the sand waves and it also reduces the intensity of the sound but due to the cascading of
the seats it will not a be a problem because each person seated in row s will be able to hear well
without obstruction
pg 10
50 PROPOSAL FOR IMPROVING THE ACOUSTICS OF THE OLD SENATE
CHAMBER
This proposal is going to address this issue through two channels which would be methods of
reducing internal noise and methods of reducing external noise
51 REDUCTION OF INTERNAL NOISE
Basically the major acoustics materials that are meant to be put in place are already there ie the
floor material the ceiling etc but few things still needs to be checked and it listed as follows
1048707 Use of textured walls making the walls in the room a rough wall will help to diffuse the
sound coming from the speaker because the direct sound is disseminated around the room when
it impacts on these wall surfaces Hence a sensation of an ominous sound is heard A smooth
surface converges the sound to a point thereby distorting it Materials like cork particle board
felt wall carpets or wall papers help diminish internal noise in the space
1048707 Ceiling Finishes itrsquos important to cover the concrete part of the room with the use of the
suspended type of ceiling covering to create a void between the concrete slab and the space
below White perforated gypsum acoustic suspended ceiling boards could be used as a finish or
wood as used in other parts of the ceiling
1048707Installation of good AC unit with good silencer to replace the ceiling fans
The installation of more air-conditioning unit will eliminate the ceiling fan which reduces the
sound produced by the ceiling fan However these AC units should be sound proof to avoid
pg 11
generating noise and the already installed could be changed or serviced when necessary to
eliminate sound it might produce due to servicing
1048707full upholstery of seats Some seats have been replaced by a plastic chairs due to maybe
dilapidation of the former ones but they need to replace them back with full upholstery seats
52 REDUCTION OF EXTERNAL NOISE
Itrsquos deduced after considering the acoustics correction steps the major ways of rectifying the
external noise has already been put in place which is the insulation of the space the only thing
needed is that of the maintenance of the acoustics materials (thick glass n textured paints where
necessary) in case of damage and the use of textured wall like that of the interior
60 CONCLUSION
During the course of this research we can deduce that the treatment of the interior compartment
of any building most especially a room that is to be used as an auditorium is a very sensitive one
and should be monitored from start to finish ie from construction level to finish level Acoustics
studying of the senate chamber as helped in various ways and it will definitely have effects on
our careers both now and in the future Its successes and failure in buildings noise sources and
control and ways of apply it during design are well understood now to a better extent
pg 12
70 REFERENCES
Prof Olu Ola Ogunsote Acoustics and noise control lecture notes
Diamant RME (1986) Thermal and acoustic insulation University Press Cambridge
httpwwwsdngnetcom
pg 13
50 PROPOSAL FOR IMPROVING THE ACOUSTICS OF THE OLD SENATE
CHAMBER
This proposal is going to address this issue through two channels which would be methods of
reducing internal noise and methods of reducing external noise
51 REDUCTION OF INTERNAL NOISE
Basically the major acoustics materials that are meant to be put in place are already there ie the
floor material the ceiling etc but few things still needs to be checked and it listed as follows
1048707 Use of textured walls making the walls in the room a rough wall will help to diffuse the
sound coming from the speaker because the direct sound is disseminated around the room when
it impacts on these wall surfaces Hence a sensation of an ominous sound is heard A smooth
surface converges the sound to a point thereby distorting it Materials like cork particle board
felt wall carpets or wall papers help diminish internal noise in the space
1048707 Ceiling Finishes itrsquos important to cover the concrete part of the room with the use of the
suspended type of ceiling covering to create a void between the concrete slab and the space
below White perforated gypsum acoustic suspended ceiling boards could be used as a finish or
wood as used in other parts of the ceiling
1048707Installation of good AC unit with good silencer to replace the ceiling fans
The installation of more air-conditioning unit will eliminate the ceiling fan which reduces the
sound produced by the ceiling fan However these AC units should be sound proof to avoid
pg 11
generating noise and the already installed could be changed or serviced when necessary to
eliminate sound it might produce due to servicing
1048707full upholstery of seats Some seats have been replaced by a plastic chairs due to maybe
dilapidation of the former ones but they need to replace them back with full upholstery seats
52 REDUCTION OF EXTERNAL NOISE
Itrsquos deduced after considering the acoustics correction steps the major ways of rectifying the
external noise has already been put in place which is the insulation of the space the only thing
needed is that of the maintenance of the acoustics materials (thick glass n textured paints where
necessary) in case of damage and the use of textured wall like that of the interior
60 CONCLUSION
During the course of this research we can deduce that the treatment of the interior compartment
of any building most especially a room that is to be used as an auditorium is a very sensitive one
and should be monitored from start to finish ie from construction level to finish level Acoustics
studying of the senate chamber as helped in various ways and it will definitely have effects on
our careers both now and in the future Its successes and failure in buildings noise sources and
control and ways of apply it during design are well understood now to a better extent
pg 12
70 REFERENCES
Prof Olu Ola Ogunsote Acoustics and noise control lecture notes
Diamant RME (1986) Thermal and acoustic insulation University Press Cambridge
httpwwwsdngnetcom
pg 13
generating noise and the already installed could be changed or serviced when necessary to
eliminate sound it might produce due to servicing
1048707full upholstery of seats Some seats have been replaced by a plastic chairs due to maybe
dilapidation of the former ones but they need to replace them back with full upholstery seats
52 REDUCTION OF EXTERNAL NOISE
Itrsquos deduced after considering the acoustics correction steps the major ways of rectifying the
external noise has already been put in place which is the insulation of the space the only thing
needed is that of the maintenance of the acoustics materials (thick glass n textured paints where
necessary) in case of damage and the use of textured wall like that of the interior
60 CONCLUSION
During the course of this research we can deduce that the treatment of the interior compartment
of any building most especially a room that is to be used as an auditorium is a very sensitive one
and should be monitored from start to finish ie from construction level to finish level Acoustics
studying of the senate chamber as helped in various ways and it will definitely have effects on
our careers both now and in the future Its successes and failure in buildings noise sources and
control and ways of apply it during design are well understood now to a better extent
pg 12
70 REFERENCES
Prof Olu Ola Ogunsote Acoustics and noise control lecture notes
Diamant RME (1986) Thermal and acoustic insulation University Press Cambridge
httpwwwsdngnetcom
pg 13
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