AR 453 Building Science 02 - Auditorium Proposal

Table of content

1.0 Introduction to group members

2.0 Case studies

2.1.

Plenary Theatre Selected material

2.2.

Connexion@Nexus Auditorium Discussion

2.3.

Kuala Lumpur Performing Art Centre (KLPAC)

3.0 Comparative table

4.0 Discussion of case studies

5.0 Auditorium proposal

5.1.

Form and layout design proposal

5.2.

Selected material

5.3.

Reverberation time

6.0 Discussion and Conclusion

7.0 References

1.0 INTRODUCTION OF GROUP MEMBERS

2.0 CASE STUDIES 2.1. PLENERY THEATRE KLCC

Layout seating arrangement: Tiered-seating Seating capacity: 500 seats Hall or room type: Seminars and smaller conferences Room volume: 16660.45 m3

Acoustic experience influences

The Plenary Theater plan is shaped in a combination of fan and rectangular shape. The rectangular shape is good for ensuring short reflection time while for fan shape yield good visibility, reflect sound to the back of the hall, suitable for speech performance,accommodate larger seating. On the above is the 9m vaulted ceiling which helps to reflect sound to the audience form the stage. Besides, double walls are use in interpreter rooms and bathrooms to ensure current events are not disturbed.

Selection of Materials

1. Ceiling Double layer Gypsum plaster board – good sound insulation and thermal conductivity, lightweight for easy installation 2. Wall Acoustic wooden composite panel – high sound insulation and diffuser Rockwool – acoustic reduction and thermal insulation 3. Floor Carpets – sound absorption Plywood – long lasting and durable 4. Others Woven fabric – chairs Curtain - covers reflective surface Advantages Good sound proof Double walls used in interpreter room ensure no disturbance on - going event.

Disadvantages Concentration of sound in the middle Concave shape at the back wall causes sound to be concentrated at the center and neglect the other seating area

Echo Reduced Uses of absorbent material to get rid of echo such as carpet and curtain

Flutter echoes Rectangular shape of the theater reflect sound repetitively causing echoes but is solved by installing acoustic wooden panel which act as a sound diffuser.

Good Sound Reflection Use of suspended angled gypsum board enable reflection of sound from the speaker to the audience to be clearer and reverberation time is lessened.

Negative sound reflection design ceilings The highlighted area of ceiling does not help much in reflecting sound to the audience due to its designed inclination angle.

2.2. Connexion@Nexus Auditorium

Layout seating arrangement: Fan shaped configuration, fall within 140° sound projection angle from the centre of the sound source on stage.

Seating capacity: 298 seats.

Hall or room type: Multi-purpose auditorium

Total volume: Approximately 1022.7 đ?‘š3

Acoustic experience influences

The fan shaped seating layout helps to preserve high frequency sounds for the audience.

The sloping areas allows a more direct angle of incidence which in turn allow less absorption and interruption by the objects in front of the seats, and the sound wave can travel towards the furthest seats in auditorium.

The design of the auditorium employs a curvilinear form where the concave will concentrate the reflected sound wave to the centre of the propagation, creating the undesirable sound foci. The sound is unevenly distributed to the audience, the centre region received the loudest sound among other areas.

Selection of Materials Floor The carpet is thick and can muffle the sound of footsteps

Wall The fibre panels are soft to the touch which can absorb sound in the auditorium

Ceiling The thickness and mass of the gypsum plaster ceiling resist panel vibration, which causes low frequency absorption and to achieve good reflections to all frequencies.

Advantages

Disadvantages

Absorptive materials used in auditorium were well taken into consideration in the design to prevent echoes; reflective materials were well taken into consideration in the design to reflect the sounds wave to the audiences.

The seating arrangement is well configured and deemed effective. It helps to achieve the most effective acoustic quality because sounds wave travel in spherical order.

The sound wave is distributed unevenly to the audience the concave shape of the auditorium concentrates the reflected sound wave to the center of the propagation.

The auditorium suffers flutter echoes on stage due to the parallel surfaces between the ceiling and the stage floor, both of which are defined as reflective materials.

Due to extensive use of absorbent materials covering of the auditorium, coupled with the relatively small volume, its reverberation time is extremely low, 0.26 seconds, which is only suitable in studio environment. (Suitable reverberation time of auditorium for both speech and music purposes is 1.5 – 2.5 seconds)

2.3. KUALA LUMPUR PERFORMING ARTS CENTRE (KLPAC) Acoustic experience influences

The front part of seats are slayed wall which resulting a combination of fan-shaped and square auditorium.

Layout seating arrangement: combination of fan-shaped and square auditorium

The rectangular shape is good for ensuring short reflection time while for fan shape yield good visibility.

Seating capacity: 504 seats Hall or room type: Large Scale Production Room volume: 8,020 đ?‘š3 Audience in the front row receives the highest incident of sound amplitude with louder volume as they are nearer to the sound source Audience in the middle row receives a moderate incident of sound amplitude volume and volume from the sound source

Audience in the last row receives the lowest incident of sound amplitude and lower volume as they are furthest to the sound source Advantage

Disadvantage

Fan shape auditorium consists splayed side wall to ensure greater seating capacity, it allow greater seating area close to stage. Usefully reflect sound energy to rear of the hall.

Single layer of brick wall is not enough for blocking external noise and it create distraction to audience

Use of sound absorption material inside the hall to absorb excess sound energy.

Seats at the corner of front left and front right easily get sound distract due to reflected incident sound simultaneously by diffusion walls while receiving direct sound from stage.

Audience sit in middle and last back rows receives sound reflected from horizontal ceiling is inefficient as there is limited amount of short delayed reflection.

Material Selection

Floor

Audience floor which covered by wool carpet

Wool carpet • Consists of individual fiber and pile tufts which produce several resonant frequencies which absorb sound.

• Improve sound quality in audience hall by absorb sound waves instead of reflected back to surface.

• Reduce impact of noise created during audience entering auditorium, dropping item, and moving furniture or equipment.

Epoxy concrete floor: • Low absorbance value to reflects the sound perfectly to audience.

Concrete wall: • act as good sound absorption but not sound insulator.

Wall

PVC concrete tube: • act a sound diffuser.

• When direct sound wave hit the tube, small frequency sound wave will distribute equally to audience due to the convex shape • Hollow inside the tube helps compress large frequency sound wave.

Wooden block: • smooth surface helps to dampen and diffuse high frequency sound.

• Some of the sound is scattered when hits wooden block and some will absorb by concrete wall sound because wooden block could not work alone in sound absorption Fabric Wall panel: • control excessive reverberation in theatre • sound absorbed through soft surface and bounce back to surrounding when sound waves hit the surface • Reduce sound delay and echoes.

Brick wall: • Naturally thick and dense of brick help to block sound wave passing through hence provide an insulation purpose.

Ceiling consists black fabric.

Ceiling

Other

• •

capable to stop sound reflection in large areas. prevent sound from escaping out of the room, absorbs noise and increase sound quality to audience.

Fabric foam chair • Each of the foam chair is covered with sound absorbent fabric to prevent the reverberation time affected by presence of audience.

• Foam is also helping in absorb sound

3.0. COMPARATIVE TABLE Plenary Theatre KLCC

Connexion@Nexus Auditorium

Kuala Lumpur Performing Art Centre (KLPAC)

Space Form

Combination of fanshaped and rectangular-shaped

Curvilinear Form

Combination of fanshaped and squareshaped

Layout seating arrangement

Tiered-seating (Combination of fan and rectangular shape with slope areas)

Tiered-seating (Fan shape configuration with slope areas)

Combination of fanshaped and square auditorium with slope areas

Seating capacity

500

298

504

Hall/Room Type

Seminars/ small conferences

Multi-purpose auditorium

Large scale production

Total Volume

16660.45mÂł

1022.7mÂł

NA

Height of ceiling

9m vaulted ceiling

8.7m high

9m high

Type of wall

Double walls

Single brick wall

Single brick wall

Ceiling Material

Double layer gypsum plaster

Gypsum plaster

Black fabric

Fibre panels

Concrete wall layered with black paint Wooden block PVC concrete tube Fabric wall panel

Wall Material

Floor Material

Seat Material

Acoustic wooden composite panel

Stage floor - plywood Audience floor - carpet

Woven fabric

Stage floor - timber veneer

Stage floor - Epoxy concrete layered with black paint

Audience floor - carpet

Audience floor - Wool carpet

Cloth-upholstered tip-up seat

Fabric foam seat

4.0. DISCUSSION OF CASE STUDIES Space form/ Layout seating arrangement: Based on the layout seating arrangement of the three case studies that we have studied, rectangular-shaped is good for ensuring short reflection time while fan shape yield good visibility, reflects sound to the back of the hall and suitable for speech performances. It helps to accommodate larger seating of crowd too while Connexion@Nexus Auditorium employs curvilinear form where the concave will concentrate the reflected sound wave to the centre of propagation results undesirable sound foci as the centre region will receive the loudest song among other areas.

Hence, the combination of fan-shaped and rectangular-shaped form helps to preserve higher frequency sounds for the audience compare to curvilinear form. Sloping areas allow more direct angle of incidence, less absorption and sound wave can travel towards the furthest seats in auditorium.

Type of Wall: Plenary Theatre KLCC uses double brick wall which enable to ensure completely no disturbance on on-going event, has a better ability to block external noise and prevent distraction to audience compare to single brick wall.

Ceiling Material: Plenary Theatre KLCC uses double layer gypsum plaster board for ceiling. The thickness and mass of the double layers help to resist panel vibration, which causes lower frequency absorption hence achieving good reflections to all frequencies. Besides it has good thermal conductivity and is lightweight for easy installation if to be compare with single gypsum plaster board and black fabric.

Wall Material: KLPAC uses PVC concrete tube which act as a sound diffuser to distribute the sound wave equally to the audience and wooden block which has a smooth surface to help to dampen and diffuse high frequency sound. Presence of wall panel helps to control excessive reverberation in theatre too as the sound absorbed through the soft surface bounce back to surrounding

when sound waves hit the surface while Plenary Theatre KLCC uses acoustic wooden composite panel which has high sound insulation and diffuser. Both are equally good if to be compare with fibre panel which are mainly focus in absorbing excessive sound of the space.

Floor Material: In terms of floor material, KLPAC will have the best selection of material in terms of aesthetic and function wise. Epoxy concrete layered with black paint is use for the stage floor. Epoxy concrete layered is slip-resistance, has low absorbance value to reflects the sound wave perfectly to audience and at the same time, it creates an elegance feel for the stage.

Audience floor – wool carpet flooring improves sound quality of the auditorium as it acts as a sound absorber and help to reduce the impact of noise.

Seat Material: All three materials used in the case studies are good in sound absorbing which act as sound absorbers and provide comfort to the audiences at the same time.

5.0. Auditorium Proposal 5.1. Form and Layout Design Proposal

Volume Stage: 356.25đ?‘š3 Audience seat:1204.5đ?‘š3 Total volume: 356.25 + 1204.5 = đ?&#x;?đ?&#x;“đ?&#x;”đ?&#x;Žđ?’Žđ?&#x;‘ The proposed program is an auditorium where speeches and performances are usually carried out here.

5.2. Selected Materials Area (đ?‘š2)

Absorption Coefficient

Absorption units

4 x 13.13 = 52.52

0.42

22.06

2 x 13.13 = 26.26

0.02

0.53

4 x 13.51 = 54.04

0.42

22.7

2 x 13.51 = 27.02

0.02

0.54

3.8 x 8.5 = 32.3

0.15

4.85

4.7 x 17.78 = 83.57

0.42

35.1

178.53

0.05

8.93

57

0.015

0.855

178

0.15

26.7

59.8

0.64

38.27 160.54

Surface/ Material Wall Left 1) Acoustic timber wall panel 2) Gypsum plaster on concrete Right 1) Acoustic timber wall panel 2) Gypsum plaster on concrete Front (Stage) 1) Curtain (Heavy Weight) Rear 1) Acoustic timber wall panel Floor Audience Floor 1) Timber veneer flooring Stage 1) Epoxy concrete layered with black paint Ceiling 1) Gypsum plaster board Seating 1) Upholstery fabric Total Absorption (A)

5.3. REVERBERATION TIME RT =

0.16 V A

RT = 1.55s

RT =

0.16(1560) 160.54

5.4. Selection of Materials Acoustic timber wall panel This material acts as diffuser to control flutter echo by sound diffusion. Its high sound absorption effect for all spectrum of noise. Also, it supplies additional reflected sound energy to every portion of the audience area.

Curtain (Heavy Weight) The curtains are designed to adjust acoustics. The reflective surface can be cover with curtain and control the reverberation by absorbing excess sound. The highly porous material acts as thousands of tiny sound traps, capturing the energy and turning it into heat. The pleated nature of curtain exposed more soundabsorbing surface, thus increasing the effective thickness and improving the low frequency sound attention.

Chairs Cushion, backrest and the rear of seat back designed with woven fabric stretched over a thick, breathable, open-cell foam padding. It adds the acoustical absorption of an empty auditorium and allow space to achieve a similar quality of sound whether the auditorium is filled to partial of maximum capacity.

Gypsum plaster on concrete The leakage of sound through the material of the block is different only in degree from leakage of sound through inadequate mortar joints. Mortar joints must always be properly finished to ensure good sound insulation and free from obvious penetrations.

Gypsum board Gypsum board wall and ceilings systems effectively help control sound transmission and used for sound isolation.

Epoxy flooring Epoxy flooring is created by combining two different materials, usually a hardener and a resin component.

The epoxy composites have very good acoustic properties.

Timber Veneer Floor Veneer is technically a thin layer of hardwood, usually thinner than 1/8 of an inch. Typically, veneer is bonded, or glued with adhesive, to a cheaper surface that is hidden below. A less expensive wood or particle board can often be found underneath.

6.0. Discussion and Conclusion Seating Arrangement Seat layout is better to arrange in fan shape to ensure good visibility, and also reflects sound to the back of the hall and suitable for speech performance.

Services and equipment noise control Noises such as air conditioning, lifts, toilets and projection equipment need to be controlled.

Use centralized air-conditional which diffuser is visible. It owns a quiet operation as the compressor-bearing is located outside.

Door Use of acoustic door act as sound barrier to noise getting in and out, control sound of ppl moving in and out

Ceiling Concave ceiling surface s suggested as geometry surface will force the energy to concentrate.

Seating Use folding fix theatre seat instead of random plastic chair as the friction between the plastic chair and floor will create noise.

By using the formula of calculating the reverberation time, the result is that the reverberation is 1.55s. As the optimum range of reverberation time of an auditorium is 1.5s – 2.5s, the value gained is within the range, thus considered suitable to fulfil the function of the auditorium.

7.0. Reference Plenary Theatre -

-

Plenary Theatre. (n.d.). Retrieved from http://www.klccconventioncentre.com/Plenary_Theatre-@Overview.aspx?space_tab=1 Yi, W. A. (n.d.). Building Science_02_Report_Case Study on Acoustic Design.

Retrieved from https:/issuu.com/winnieawy96/docs/building_science_2_presentation_sli

Nexus@Connexion Auditorium -

Szokolay, S.V. (2004). Introduction to architectural science: the basis of sustainable design. Oxford: Architectural Press McMullan, R. (2012). Environmental science in building. 7th. Ed. Basingstok: McMiLan

Kuala Lumpur Performing Art Centre (KLPAC) -

E. (n.d.). Acoustic Study on Auditorium. Retrieved from https://issuu.com/enhuey/docs/bsc_acoustic_ Pentas 1, Our Venues. The Kuala Lumpur Performing Art Centre. http://www.klpac.org/about-klpac/facilities/