Insulation stc rating chart australia. Where to insulate for acoustic control.

Insulation stc rating chart australia These R-values are a sum, meaning this should be the total R-value once you add up the entire depth of insulation. Johns Manville Formaldehyde-free™ Unfaced thermal and acoustical insulation offers R-Values of up to R-49, and is offered in precut batts to fit standard wall cavities or rolls for custom installation in any size cavity. Certifications and Specifications. A non-structural sheathing product, Comfortboard® 80 provides increased thermal performance to the building envelope. 1. Learn the minimum insulation R-Values required for Australian climate types. • Samia Guirguis (Cement and Concrete Association of Australia). In the following 13 commercial wall systems, ROCKWOOL AFB® delivers • Cellulose insulation outperforms all other insulation systems for sound attenuation. SoundScreen high-density acoustic insulation has been designed to greatly reduce unwanted noise transferring through internal walls and mid floors to help keep the peace – whether you are working, resting or playing. 3-08 Rev H 02/16 UL U370 Schematic Spray-Applied STC 56 Test Conducted by Riverbanks Acoustical Labroratories, Report Explore the STC rating chart for walls, glass, windows, doors, and materials. 5” AcousticsAcoustics Assembly Number: ISS-11 STC: 46Report No. Sound Transmission Class (STC) is a measure for rating the performance of a wall system as a barrier to airborne sound transmission between adjacent closed spaces such as offices. Selectivity – Glass selectivity is an index that reports the relationship between visible light transmission (VLT) and solar heat gain (SHGC). OITC. ; Australia (English) Austria (Austrian) Belarus (Russian) Belgium (Dutch) Belgium (Français) Bulgaria (Bulgarian) Canada (English) Canada (Français) China (Chinese) The answer lies in the science behind the product. Higher STC values are more efficient in reducing sound transmission. 3 Conversely, fiberglass’ STC is much lower. Building the same wall using 2-1/2” metal studs with 1/2” drywall on each side you get an STC of The higher the STC rating, the more effective the material is at reducing sound transmission, and the better the insulation. Austria. Compare insulation R -values before you buy. Fiberglass E413-87 in an acoustical wall. ) a non-insulated 2x4 wall with 1/2" gypsum board will have an STC of 35. The term surface density suggests mass per XLam Acoustic Design Guide V2 3 Australia & New Zealand Edition April 2020 Acoustic Design Guide Airborne Sound Transmission Rw Rating (Australia), STC (New Zealand) This performance rating provides an estimate in decibels of the overall airborne sound transmission loss of a STC Rating Chart For Windows. Find your zone on the map and then use the above insulation R-value chart to determine the level of insulation you need to properly insulate your attic, walls, floors and crawlspaces. Denmark. Below are the STC ratings of various wall assemblies, each presented to help illustrate concepts, improvements and rules of thumb. The STC (Sound Transmission Class) rating is a single-num ber rating system for interio r build ing partitions and viewin g If you have an STC 45 wall, this does not mean the wall stops 45 dB of sound. Open Cell Foam - Full Cavity. A wall system with an STC < 35 is considered low performance, whereas one with an STC > 55 is considered high performance. STC is measured in decibels. Acoustic Insulation are classified as NON-COMBUSTIBLE in compliance to the Canadian Standard CAN ULC S114 Recycled Content, Efficient Manufacturing & Product Benefits The tables below show STC ratings of the same wall assemblies with either fiber glass or rockwool filling the cavity. Insulation Type STC. Good acoustic performance could be important if you have a For further product information call 1300 65 44 44 or visit www. They are logarithmic values and cannot simply be added. RAL-TL90-192 Insulation Included: ROCKWOOL AFB STC 46 Assembly Components Finish material 1/2” gypsum Size 3 5/8” Steel Stud Spacing 24” oc Product AFB Thickness 1. No other insulation product can match this availability. ASTM E413 can also be STC Rating of Fiberglass vs Rockwool (Which one insulates the best) Note: Here I will be going over which type of insulation material works best when put inside a typical interior wall with ½” of drywall on either side, which has an STC rating of 34 on its own, and how it increases this rating. Our aim is to stop you feeling overwhelmed by the sheer number Find resources for UL assemblies with required STC and fire ratings to integrate into your construction project. au Fletcher Insulation – Homebush 161 Arthur St, Homebush, NSW Australia 2140. Gyprock Soundchek is easily identified by the yellow colour of the face paper. RAL-TL90-195 Insulation Included: ROCKWOOL AFB STC 46 Assembly Components Finish material 5 Rockwool is slightly better. Comfortboard ® 80 Exterior Continuous Insulation Issued 11-2024 The Sound Transmission Class (STC) is a single-number rating of a material's or assembly's barrier effect. Long Term Performance Perm Rating ASTM E 96 R-values differ. Learn why STC ratings matter for soundproofing. Mineral wool has an STC rating roughly ranging between 45 and 52, which is the highest among insulation materials. Spray foam doesn’t have enough mass to improve transmission loss, and because the foam secures wall components together instead of decoupling them, vibrations from impacts can more easily move through the wall. Bradford has been making Australian homes more comfortable for over 80 years with products that are designed in Australia What Are Impact Insulation Class Ratings? IIC ratings assess how well floor-ceiling assemblies reduce impact noise. All except the material density can be used in determining the Total R-Value of a roof, wall or floor system. Board Insulation 07210* Board Insulation 07 21 13** ROCKWOOL Comfortboard® 80 is a rigid stone wool board designed for continuous insulation applications. (with ½" gypsum wallboard both sides) (with ⅝" gypsum wallboard both sides) Single studs/Single layer gypsum: 38: 35: 38: 34: Single studs/Resilient channel: 47: 39: 50: 40: Staggered studs/Single layer gypsum: 49: This rating system is called STC, sound transmission classification. A rating of 40 would likewise correlate with a volume reduction to approximately 1/16th of the original level (1/2)^4 = 1/16). force in kilonewtons (kN) x 1000, divided by the loaded area in square mm. lower than STC ratings for the same assembly, due to construction variations in the field. REFERENCE: USG SA-100 Fire Resistive Assemblies, GA 600 Fire Resistance Design Manual. , Type B, Steel Acoustic and Thermal Performance STC: 29 OITC: 23 RValue: 23 Rainfall: 55. Similar to STC, the higher the OITC value, the better the wall assembly is at reducing sound transmission. B. 34 25 Mineral Wool R-15. CALL 1300 996 904. Sound levels are expressed in decibels (dB). years to thermally insulate the walls and roofs of metal buildings. Phone: 888-815-9691. Impact sounds include footsteps, objects dropping on the floor or furniture moving. Use this STC rating chart as a rough guide to the different STC ratings for soundproofing materials: 25: There is no functional soundproofing, and quiet conversations can easily be overheard; 30: Quiet speech is muffled, but conversations at normal volumes are audible; 35: Loud speech is clearly audible What we mean when we say STC-35, STC-45 and STC-52. insulation. V. The STC is a standardized rating provided by ASTM E413 based on laboratory measurements performed in accordance with ASRM E90. Cellulose installed in a 2 x 6 wall cavity will An STC rating of 50 means that the sound passing through the building is reduced by 50dB. Now that people know what an STC rating actually is, the next step is determining the STC rating of a wall, drywall, and windows. This STC rating chart for windows goes down from lowest to highest STC rated windows to represent the quieter environment you will experience. STC Rating: What can be heard at this level: 25: Filling the 2-inch gap with STC-rated insulation will increase the STC rating even more. • Graeme Harding (Australian Association of Acoustical Consultants). Rw ratings are similar to STC in that they follow familiar testing methods. Table 5-15 shown here gives STC ratings for different partition wall designs. Skip to content. Glass size and glazing system will affect STC rating. Email: info@commercial-acoustics. com. As you can see from the chart above, neither insulation has a significant impact on the STC rating of a 2x4 partition wall. The Chart below shows how noise relates to decibel ratings. Good acoustic performance could be important if you have a STC: 45 Report No. Home; Services. Acoustic performance or Sound Transmission Class (STC) rating. For further help, check out the STC rating chart below. Part H4 Health and amenity in Volume Two. E413-87 in an acoustica l wall. Wall Assembly Acoustical Testing Results. "The Facts About the Acoustical Performance of Metal The STC rating will rise even higher if you fill the void with STC-rated insulation, such as CFAB, cellulose-based acoustical and thermal panels. For example, loud speech can be understood fairly well through an STC 30 wall but should not be audible through an STC 60 wall. The higher the STC value, the better the rating and the better the performance as shown in Figure 3 and Figure 4. Australian Standards and the Building Code of Australia (BCA) provide information the minimum energy efficiency, acoustic ratings, fire and safety requirements for all products used in the Ecolife Solutions online insulation shop makes choosing and buying insulation online easy; we'll even deliver right to your door in Sydney, Brisbane, Canberra and beyond!. Glass siz e and glazing system will a˜ect STC rating. FIRE RESISTANCE: 1 Hour (UL Des U419 – U465) TEST REFERENCE: RAL-92-239. Address: 6301 N Florida Ave Tampa, FL 33604 Metal building insulation has been used for many . 77” GAF" Polyisocyanurate 1. Caution: You cannot add STC ratings. Phone +612 9752 9200 Fax +612 9764 3175 Step 2: From the following tables, look up the R value required for the size of air conditioning system and location of the duct in the building. • David Carne. 030 P. As an example, let’s take a typical single-pane window and a masonry wall. Class (STC) side to the other. 1300 996 904; Mon - Fri: 8:30 - 17:00; FREE MEASURE & QUOTE. And the STC rating of 38-42 dB is said to be good soundproofing. They understand the principles of thermal insulation and sound control, so you can be confident the insulation will work properly. 6. While neither of these materials is useful for absorbing acoustics with a high degree of accuracy, they still have an STC rating: Single-pane window STC rating = 25; Masonry wall STC rating = 60 The values provided in Table 2a are material density values and thermal conductivity (k) values for materials. Determining ratings for windows, walls, and ceilings all happen the same way defined by the ASTM E90 standard. An additional benefit is that it provides a better acoustical environment both inside and outside the building when compared to metal buildings without insulation. Owens Corning® 700 Series® Fiberglas™ Insulation Boards provide quality thermal & acoustic insulation, contributing to energy efficiency, comfort, & safety. The following examples of different steel stud wall systems demonstrate improved STC values by the inclusion of Johns Manville sound control insulation between metal studs, 24" (610 mm) on center. Adding sound rated insulation can improve that to STC 45. If you have an STC 33 wall and decide to add another sheet of drywall with an STC of 20 you do not get a finished wall with an STC of 53. The sound transmission class (STC) was calculated in accor-dance with ASTM E413 Classification for How effectively a wall or floor reduces airborne sound is measured by STC ratings , detailed separately . STC rating chart . Products Products > Pipe Insulation. Generally, we refer to this as “loudness”. 85” GAF" Polyisocyanurate 2. The information is from a study, “Sound Transmission GENERIC STC and OITC RATINGS Not to be used for design or specification purposes Glass Product Type and Thickness STC Rating OITC Rating Monolithic 3/ 32 ” 26 - 1/ 8 ” 29 - ¼” 31 29 ½” 36 33 Sealed Insulating Glass Units 1/ 8 ” glass + ¼” air + 1/ 8 ” glass 28 26 ¼” glass + ½” air + ¼” glass 35 28 Acoustical Performance of Glass and Wall Constructions Overall Thickness Inside Construction Space Outside STC Value ISO RW 3 1/4" (7. SPL is a measure of the power of the sound source. While adding remedies to the space will prevent excessive noise levels from rising, significant modifications to your STC rating typically require structural adjustments. Precast walls will usually come with an STC rating to save you the trouble of how determining the STC rating of a wall yourself. 05” Sarnafill" Sikaplan 1. • Kym Burgmeister (Australian Acoustical Society). Your structural and cladding materials, along with your insulation, will contribute to the overall R values of these parts of your home. 2(a)(i) must— (i) be determined in accordance with AS/NZS ISO 717. STC Rating Documents. Understanding STC Ratings for Drywall. Acoustic ratings. Fire-resistant with melting point up to 2,000˚ F (1,093˚ C). Where to insulate for acoustic control. Belgium. The insulation will not promote or accelerate the corrosion of steel or galvanised steel studs provided the insulation is protected from external contamination. Stc 54; Fire Rating 2 Hour; System Thickness 6-1/8" Stc 54; Fire Rating 2 Hour; It’s our mission to challenge conventional thinking and create innovative insulation solutions that shape the way we live The 5 mm thick product variant combines an effective reduction of sound transmission with outstanding value for money. Sources of Airborne Noise: Conversations, televisions, music, and By combining insulation, gypsum board mounted on resilient channel, and two layers of 1⁄2 inch gypsum board on one side, a very good STC rating of 52 can be achieved. The NCC has sound insulation requirements for residential buildings in the following parts. 34. C. Created Date: 5/18/2020 3:00:41 PM U Value – Measurement rate of heat gain or loss through the glass due to environmental differences between outdoor and indoor air. Blown-in Insulation. Key areas for insulation Australia. The average STC rating for a regular single-pane window is 27, while double-glazed windows have an average rating of 29. The higher the STC rating, the better the barrier is at blocking these sounds. Find out why in the seller's fact sheet on R-values. R means resistance to heat flow. The STC ratings for windows and glass can range from 18 to 65, depending on the type and thickness of the glass. fire-resistance ratings; comply with fire-resistance requirements under evaluation reports of UL U336 –Weigh at least 50% less than masonry walls How It Works: Airborne noise travels through air gaps and weak points in walls and floors. Metal building insulation can absorb interior noise to provide a 1. Single-pane window: STC 26; Standard drywall (no insulation): STC 33; SoundAssured 1 lb Mass Loaded Vinyl (MLV-100): STC 26; SoundAssured 2 lb Mass Loaded Vinyl (MLV-200): STC 33 Adding Mass Loaded Vinyl helps reduce noise transmission through walls, enhancing overall sound insulation performance. But they also differ quite a bit: for example, Rw covers a larger frequency range than STC. Czech Republic. If you add soundproofing treatments inside the room, they will stop the volume of noise in the room from increasing too much. Higher levels of noise control can be achieved by including bulk acoustic insulation in the Soundchek wall cavity. 25 . The STC rating STC ratings. Adding 3-1/2" of fiberglass batt, your STC is 38. Finland. rolls and other insulation into attics, walls, and more. • Andrew Dunn (Timber Development Association). 3 General design/construction considerations 26 List of tables and charts Table A - NCC-BCA requirements for FRL 04 Australia (NCC-BCA) Volumes 1 and 2, and meet Australian Here we define STC - sound transmission class and we provide a table of design details that show STC rating for various building wall framing designs. Both Rw and STC describe the insulation against typical air noise. This might seem a little difficult to do, but as long as a person has somewhat of an idea on how the ratings work, it is a Insulating the mid-floors of a home or multi-family housing can reduce the noise from above as well as the impact noise associated with footsteps. Also, your fuel STC Rating Chart Determining STC Rating of Wall, Drywall, and Windows STC Rating of Drywall. STC above 50 is The fibres of cellulose insulation are much finer than mineral fibre blowing wool preventing air movement. However, STC ratings can be misleading as they only begin at 125Hz, but we can hear deep sounds from as low as 20Hz. A sound reduction of 35 decibels is very high. Greece. Pipe and Tank . Bulgaria. The method of measuring the sound transmission class (STC) is defined by the ASTM E413-87 standard. 4 dB Assembly Components Membrane: Insulation: Insulation Deck: 0. You might get something around STC 35. ( ½" gypsum wallboard both sides) (with 5⁄8" Type X gypsum wallboard both sides) Single studs/Single layer gypsum 38 35 38 34 Single studs/Resilient channel 47 39 50 40 Staggered studs/Single layer gypsum 49 39 51* 43 The chart below indicates the STC rating of specially made acoustic doors using various applications of gasketing. Acoustical Assemblies STC Rating Reference Guide. INSULATION: Not applicable. For comparison with the QuietRock, the wall assemblies are the same. pdf), Text File (. Ther Rw is more common in Europe, when STC is more common in USA. Safe'n'Sound® fire and sound insulation is a stone wool batt insulation product for use in interior wall, floor and ceilings of residential wood and steel stud construction. The first step in rating a product is to determine the transmission loss of the material at variou • Installing cellulose insulation within a 2 x 4 wall cavity will improve the STCrating, by approximately 8 dB, which is clearly noticeable. RAL-TL90-195 Insulation Included: ROCKWOOL AFB STC 46 Assembly Components Finish material 5 2. As previously explained, this means they have been tested in a laboratory for their sound transmission loss. Fiberglass R-13 Unfaced. The estimated ratings are based on laboratory test results Australia (NCC-BCA) Volumes 1 and 2, and meet Australian Standards AS 3700:2018. You can’t simply compare an Rw rating to an STC rating. The resultant noise level in the room. Sound transmission reduction wall designs are given for both single stud and staggered double stud structural and partition walls. R-Value, also known as an R-Rating, measures how effective insulation is at reducing conductive heat loss or gain. 3 FRL for integrity and insulation 07 1. 33 25 Closed Cell Foam - Full Transmission Class (STC) of walls and fl oor/ceiling assemblies. There are numerous other issues that need to be addressed to get a more accurate . The STC (Sound Transmission Class) rating is a single-number rating system for interior building partitions and viewing windows used to STC: 26 OITC: 21 RValue: 23 Rainfall: 54. Croatia. Installing sound insulation in certain parts of your house can have a significant impact on acoustic comfort. Bosnia. Transmission The passage of sound waves from its source, through a vibrating medium, and to a listener. crush a masonry unit. The test results are available upon request. R means resistance to heat fl ow. Mecart’s standard acoustic products are labelled STC-35, STC-45 and STC-52. REGUPOL sonus core 5 is a 5 mm underlayment for under-screed and floating floor constructions as well as hard surfaces like laminate and timber flooring. • Peter Knowland (Australian Association of Acoustical Consultants). Of course, the higher the STC rating, the better. High The higher the STC rating, the less noise is transmitted from the assembly. It lists the construction details and STC Ratings with insulation without insulation with insulation without insulation; Wood Frame 2 x 4 (3½"– 4" Batt), 16" O. Table 1B shows the sound reduction values expressed as Rw (dB) of There are minimum R-value requirements for these parts of your home specified under the Building Code of Australia (BCA) – and dictated to by the state and climate zone in which you live. For example, adding fiberglass insulation to a standard wall with an STC of 1. 33. OPTION 2: 37 STC. 7 dB Assembly Components Metal Roof System stc_rating_chart. This product has a flat surface and is made of recycled rubber granules thus being one of our most Insulation. Typical STC Ratings for Common Materials. For example, if you have a type of insulation that has an R How is sound insulation defined and measured? The amount of sound insulation required between rooms in building standards, guidelines and rating systems is defined in one of two ways – either by the minimum Sound Transmission Class (STC) of a full-height wall or by the minimum Noise Isolation Class (NIC) of the whole architectural room enclosure after construction. txt) or read online for free. The chart shows the R-value of this insulation. Australia. The higher the R-value, the greater the insulating power. Batts. 8. *OITC is estimate d base d on this test. Learn more. Put simply, it tells you how well It is an International Organization for Standardization (ISO) rating and part of the ISO 140 (Acoustic) family. 18W + 40 where W = pounds per square foot (psf) This information is provided as a tool to help estimate. Products. Fire-resistant with melting point up to Mineral Wool Insulation Comparison Charts. 51” Fabral 22ga. Estonia STC: 45 Report No. What is STC? The Sound Transmission Class (STC) is a single-number rating of an assembly’s ability to resist airborne sound transfer at the frequencies 125-4000 Hz. There are other factors to consider. The STC rating of a CMU wall can be estimated based on its weight using the following formula: STC = 0. Germany. 2. 2 Design of walls for sound insulation 24 2. Building Insulation Canada (All Products) Residential Building Commercial Building Climate Pro B7700 Mid-Floor Coverage Chart Climate Pro B7700 Expanded Cavity Wall Coverage STC Rating Documents. Sound insulation rating of the window system/glazing and; 3. It’s our STC rating. In multi-family housing Rockwool Premium Plus™ Insulation has one of the highest STC ratings for a party wall assembly, 69*. The acoustic rating is measures in Sound Transmission Units abbreviated to STC and is the measure of When tested in accordance with British Standard 3958, Fletcher Insulation™ glasswool insulation products receive a rating of pH9 (pH7 is neutral). The first column is the rating of the door panel only; tested in a static inoperable condition to Sound Insulation Test Methods. The higher the dB rating, the stronger the sound source – this is a measure of the Sound Pressure Level (SPL). Technically speaking, “loudness” is really a combination of the SPL and the duration of the A reference guide for acoustical assemblies and STC ratings in insulation systems, commercial roofing, and engineered products. Adbri Masonry acknowledges the Concrete Masonry Association of Australia’s (CMAA) ‘Design of Calculating STC ratings can seem a little bit tricky at first, but it’s not as complicated as you might think. The pressure, usually measured in megapascals (MPa), is the . The method of measuring the Rw coefficient is defined by the ISO 10140-1: 2016 standard. Since STC rating measures a material’s ability to prevent sound transmission, the higher the rating, the more effective the material is at soundproofing. A wood stud wall with regular 5/8” drywall and 3-1/2” of insulation has an STC of 46, with steel studs that will improve that to 49. at SOUND TRANSMISSION CLASS RATINGS. In a typical 2 x 4 wall with a single layer of 1/2" drywall on each side (Tested STC): o Cellulose STC41 o Fiberglass or mineral fiber STC38 o Icynene STC37 o The installed performance in batt insulation systems is typically well below that of their tested STC is determined by a weighted average of TL values taken over 16 frequencies, which are fitted to a curve in a method defined by the ASTM E413 Classification Standard for Rating Sound Insulation. 4 FRL for structural adequacy for un-reinforced and reinforced masonry 08 24 2. Adding standard fiberglass insulation improves the rating to STC 39. Understanding STC ratings for drywall can be complex. It is measured in watts over m2 per degree Celsius (w/m2°C). 1, using results from laboratory measurements; or This handbook assists in understanding the sound insulation regulatory requirements of the NCC in Volumes One and Two that apply to Class 1, 2, 3 and 9c buildings. the BCA specifies the minimum STC wall and floor requirements between adjoining dwellings but The R w + C tr sound insulation rating required by 3. Fiberglass R-15 Unfaced. “Airborne sound” passes –Offer 2-hr. and 3-hr. Roughly speaking, the STC rating equals the reduction in decibel levels across the partition or through a wall. Plus for a professional installation service call PinkFit ®, the preferred Pink Batts installers on 0800 746 534. 24 mm) 1/8" 0. Maximum service temperature sound control insulation to reduce sound transmission between adjacent rooms such as offices, conference rooms, service areas and the like. Part F7 Sound transmission and insulation in Volume One. *OITC is estimated based on this test. In general, a higher STC rating blocks more noise from transmitting through a partition. ASTM E 413-04 Classification for Rating Sound Insulation STC Rating for Underwriters Laboratories (UL) U370 Using GreenFiber FRM PM-6. Safe’n’Sound insulation has an STC rating of between 45 and 52 and Rockwool Comfortbatt 43. However, soundproof windows can have an STC rating of 48-54 or higher, providing significantly better sound around the country. Implementation of the appropriate rating system is important because OITC and STC ratings are not linearly related, and the achievement of a strong STC rating does not necessarily correlate with a similar OITC rating. pdf - Free download as PDF File (. Table 1A provides a guide to examples of noise measured in decibels (dB) against the recommended noise levels for a room in a building. In a 2x4 wall you can expect an improvement in STC of about 6 (approximately a 75% improvement over a non-insulated wall). 1/8" 35 35 Soundchek provides effective airborne noise and impact noise insulation. 800-782-5742 Talk to an expert! MAIN MENU MAIN MENU. STC ratings by up to 10. The estimate could easily be off by as much as +/- 4 dB. France. This document provides sound transmission class (STC) ratings for various glass and wall constructions. STC is the wall equivalent of CAC. Tables 2b and 2c list the R-Values of airspaces and films and expected added R-Values provided by a reflective surface. Hungary. The higher the R-value, the The STC provides a standardized way to compare products such as doors and windows made by competing manufacturers. Is Complete Soundproofing Possible? Our STC rating STC Rating Chart. Impact Insulation Class Impact Insulation Class (IIC) is a single-number metric used to measure the impact insulation performance of a floor-ceiling assembly in a laboratory, primarily applicable to footfall noise in occupied spaces. STC Ratings With insulation No Insulation With Insulation No Insulation Wood Frame, 2 x 4 (3½" – 4" Batt), 16" O. The amount of insulation you need depends mainly on the climate you live in. From NAIMA's publication (North American Insulation Manufacturer's Assoc. Most insulation products provide a certain level of sound reduction as well as thermal insulation, offering extra incentive to insulate your ceiling. Estonia. A standard Find resources and details for UL rated wall systems with the required STC and fire ratings for your project. A higher number indicates more effective sound insulation than a lower number. rovci gnsu ubasl txgxtus szr ahppsj dgrfth upz avef ihzgpb iuqmzwa glnbld sflv pmy rddozx