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Perlite in Sound Insulation Applications Perlite in Sound Insulation Applications lightweight concrete oor installation with an oven Discover the many sound-blocking and e versatile nature of expanded perlite allows dry density of 1,300 kg/m³, at a thickness of 50 mm Applications sound-absorbing uses for expanded perlite. it to be used in the manufacturing process of both (2 in.) applied directly (bonded) on 200 mm (8 in.) sound-blocking and sound-absorbing products thick reinforced cement concrete (RCC) slab achieves an airborne sound rating of: Rw (C; Ctr) = 56,1 (-2 ; Types of Noise globally. When it comes to noise protection in buildings, -6) dB. (Figure 2 and Figure 5). both sound-absorbing and sound-blocking (or sound- Airborne Noise – When airborne noise strikes a Sound-Absorbing Perlite-Based Products – Perlite Lightweight Concrete In-Fill Partition Wall proong) materials come to mind. Each oers unique oor or ceiling, the surface is set to vibration by the Expanded perlite is traditionally used as a primary Systems – A sustainable drywall partition developed properties that make them suitable for specic uctuating pressure of the sound waves. is constituent in the production of lightweight sound using perlite lightweight concrete in-ll at a density of applications. vibration is what radiates sound into the air on the insulating panels and ceiling tiles. e intrinsic 1,000 kg/m³ gives this partition wall system a mini- other side. porous nature of lightweight expanded perlite absorbs Processes that Govern the Absorption sound waves and reduces the reverberation time. mum 4-hour re rating and complies to 45 DnTw + Impact Noise – Impact noise is caused by an object of Sound by Acoustic Materials Another option is the use of perlite as ller in Ctr dB for intertenancy walls (Figure 3). is is striking or sliding on a oor, such as footsteps, First, in porous materials, sound energy is trans- spray-on absorbers. During spraying, perlite is mixed achieved with a thickness of 200mm (8 in.). Table 1 moving furniture or a door slamming. It can also be formed into heat by the viscous forces at work when with a binding agent and water to produce a so illustrates the sound performance index of the perlite- caused by an appliance, such as a dishwasher or sound propagates through materials. Second, sound is lightweight material with a coarse surface texture and based partition system with varying thicknesses. dissipated by frictional forces when acoustic materials shower, which transmits its vibration to the building high sound absorption characteristics[1]. In one Further Benets of Perlite When Used as a Filler structure. are set into vibration by the incident sounds. application, spray-on absorber containing perlite in Construction Applications: achieved a NRC value of 0.70[2]. Excellent thermal insulation PERLITE SOUND INSULATION APPLICATIONS Sound-Blocking Perlite Products – Expanded levels of sound insulation. For example, the airborne Lightweight SOUND BLOCKING SOUND ABSORPTION perlite is an essential constituent of perlite lightweight sound insulation per Approved Document E–UK Safe to handle; non-toxic, inert and concrete. Densities greater than 1,000 kg/m3 (62 for new dwellings is 45 DnTw + Ctr dB. By inorganic material Stop or reduce sound transmission Reduce Echo 3 Fireproof and non-combustible Block a wide spectrum of frequencies Improve overall sound quality lb/ ) oer a higher degree of sound-blocking. By denition, this is the weighted Sound Reduction Typical dense, thick and heavy materials Can absorb specic frequencies varying the amount of perlite used in the mixture, Index with the addition of a low frequency sound Resistance from corrosion from most chemicals VALUE OF PERLITE Does not block noise from entering or one can achieve a balance between the weight of the correction factor (Ctr). Cost eective leaving room Incorporating perlite serves to lighten sound- overall structure, and the need for sound blocking Perlite manufacturers have developed a variety of Low environmental impact blocking material and enhance performance VALUE OF PERLITE sound-absorbing layer Perlite oers excellent sound dampening due to sound-blocking wall installed on the wall surface lightweight and porous nature How Perlite Works as a Sound Absorption/ Measurement Techniques and Units Blocking Material Reductions in unwanted sound transfer are e characteristic cellular structure of perlite and typically expressed in terms of the Sound Transmis- the successive air compartments hinder the propaga- sion Class (or STC) in the U.S., or the Sound tion of sound waves, rendering it an ideal ller for Reduction Index (SRI) outside the U.S. is is an sound-blocking and sound-absorbing applications. integer rating how well a building partition reduces When used as a ller, sound waves can be consumed airborne sound. e STC rating roughly reects the and absorbed by multiple levels due to the combina- decibel reduction in noise that a partition provides. solutions for harnessing the benets of perlite light- tion of an interconnected pore structure and cavity In comparing sound absorbing materials for noise weight concrete to meet the stringent local building resonance sound absorption structure, resulting in a control purposes, the Noise Reduction Coecient performance. For a detailed explanation of perlite code requirements. For example: higher performance, sound absorption/blocking (NRC) is commonly used. NRC is the average usually lightweight concrete, see Perlite Institute info sheet: Perlite Lightweight Concrete Floor Sound-Blocking material. stated to the nearest multiple of 0.05, of the coecient Transit Mix Perlite Lightweight Concrete. Solutions – Perlite lightweight concrete oor screed is at four frequencies 250, 500, 1000 and 2000 Hz. Most building codes now require oors, external used to reduce unwanted sound transfer between walls, and intertenancy walls to comply with varying oors in a multilevel building. A typical perlite Perlite in Sound Insulation Applications Applications lightweight concrete oor installation with an oven e versatile nature of expanded perlite allows dry density of 1,300 kg/m³, at a thickness of 50 mm it to be used in the manufacturing process of both (2 in.) applied directly (bonded) on 200 mm (8 in.) sound-blocking and sound-absorbing products thick reinforced cement concrete (RCC) slab achieves an airborne sound rating of: Rw (C; Ctr) = 56,1 (-2 ; Types of Noise globally. When it comes to noise protection in buildings, -6) dB. (Figure 2 and Figure 5). both sound-absorbing and sound-blocking (or sound- Airborne Noise – When airborne noise strikes a Sound-Absorbing Perlite-Based Products – Perlite Lightweight Concrete In-Fill Partition Wall proong) materials come to mind. Each oers unique oor or ceiling, the surface is set to vibration by the Expanded perlite is traditionally used as a primary Systems – A sustainable drywall partition developed properties that make them suitable for specic uctuating pressure of the sound waves. is constituent in the production of lightweight sound using perlite lightweight concrete in-ll at a density of applications. vibration is what radiates sound into the air on the insulating panels and ceiling tiles. e intrinsic 1,000 kg/m³ gives this partition wall system a mini- other side. porous nature of lightweight expanded perlite absorbs Processes that Govern the Absorption sound waves and reduces the reverberation time. mum 4-hour re rating and complies to 45 DnTw + Impact Noise – Impact noise is caused by an object of Sound by Acoustic Materials Another option is the use of perlite as ller in Ctr dB for intertenancy walls (Figure 3). is is striking or sliding on a oor, such as footsteps, First, in porous materials, sound energy is trans- spray-on absorbers. During spraying, perlite is mixed achieved with a thickness of 200mm (8 in.). Table 1 moving furniture or a door slamming. It can also be formed into heat by the viscous forces at work when with a binding agent and water to produce a so illustrates the sound performance index of the perlite- sound propagates through materials. Second, sound is caused by an appliance, such as a dishwasher or Figure 2 • A Sound Pressure Level graph showing perfor- lightweight material with a coarse surface texture and mance results for a lightweight concrete sound-blocking oor based partition system with varying thicknesses. dissipated by frictional forces when acoustic materials shower, which transmits its vibration to the building high sound absorption characteristics[1]. In one at dierent frequencies. e higher the Sound Reduction Further Benets of Perlite When Used as a Filler are set into vibration by the incident sounds. structure. Index (SRI), the greater the reduction in unwanted noise in Construction Applications: application, spray-on absorber containing perlite transfer (blue line). (Courtesy of Gulf Perlite LLC, Dubai) achieved a NRC value of 0.70[2]. Excellent thermal insulation Sound-Blocking Perlite Products – Expanded levels of sound insulation. For example, the airborne Lightweight perlite is an essential constituent of perlite lightweight sound insulation per Approved Document E–UK Safe to handle; non-toxic, inert and concrete. Densities greater than 1,000 kg/m3 (62 for new dwellings is 45 DnTw + Ctr dB. By inorganic material lb/3) oer a higher degree of sound-blocking. By denition, this is the weighted Sound Reduction Fireproof and non-combustible varying the amount of perlite used in the mixture, Index with the addition of a low frequency sound Resistance from corrosion from most chemicals one can achieve a balance between the weight of the correction factor (Ctr). Cost eective overall structure, and the need for sound blocking Perlite manufacturers have developed a variety of Low environmental impact SOUND PERFORMANCE OF WALL INSULATED WITH PERLITE LIGHTWEIGHT CONCRETE IN-FILL SR. DESCRIPTION ACOUSTIC RATING FIRE RATING (1) (2) (3) 100 mm 150 mm 200 mm How Perlite Works as a Sound Absorption/ Measurement Techniques and Units (STC) (DnTw + Cu) 1 100 mm partition with two sides cement boards 4 hour min.
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