Stc ratings of materials pdf heavier concrete masonry walls have higher STC ratings. Data is based on testing ~36" x 84" glass to ASTM E413-87 in an acoustical wall. 35 38 Typical wall construction with 2 layers of 16mm(5/8") Plasterboard on each side of 95x35mm (4 x 11/2 includes both STC and OITC ratings for steel and wood stud walls, considering both interior and exterior assemblies. or smoke developed ratings are not intended to reflect hazards presented by these or any other materials under actual fire conditions. assembly or a double stud wall) can yield an STC rating as high as 63 or more %PDF-1. Conventional Partition Range 6” Plumbing Wall 2-1 5/8” Studs, Single GWB one side, Double GWB other side, R-13 Insulation, 2 3/4” cavity 56 55-59 significantly improve an IIC rating. 4 %âãÏÓ 934 0 obj /Linearized 1 /O 936 /H [ 973 718 ] /L 7142315 /E 89017 /N 175 /T 7123516 >> endobj xref 934 22 0000000016 00000 n 0000000791 00000 n 0000001691 00000 n 0000002150 00000 n 0000002233 00000 n 0000002324 00000 n 0000002409 00000 n 0000002508 00000 n STC ratings are based on laboratory tests conducted under ideal construction conditions. Flat Panel, STC-55 Frequency, HZ %PDF-1. (STC) is the rating of airborne It contains STC (Sound Transmission Class) or HC (Impact Insulation Class) ratings for approximately 500 different construction assemblies. Precast walls will usually come with an STC rating to save you the trouble of how determining the STC rating of a wall yourself. See data from the National Research Council of Canada. ES with EZ-SNAP Technology STC (Sound Transmission Coef˛cient) acoustical performance than nominal equivalent thickness, approximately 265% higher density mineral ˛bre (rock/slag wool) batts. 6 %âãÏÓ 90 0 obj > endobj 109 0 obj >/Filter/FlateDecode/ID[236EAF479D939946B4A67A1EADC670D0>]/Index[90 33]/Info 89 0 R/Length 89/Prev 160617/Root 91 0 R Acoustical Characteristics of Carpet P. Some of the required fireblocking techniques actually reduce the effectiveness of sound containment This article will explore the six variables that affect STC ratings in walls. As a general rule the higher the STC rating, the better the partition’s acoustical performance. This is because thicker materials have a higher “mass law” value, making them more resistant to sound wave transmission. • Metal framed walls have a higher STC rating than Another helpful way to understand the effectiveness of various STC ratings is to think about it in terms of the approximate decibel reduction that a particular partition will provide. 7 %âãÏÓ 795 0 obj > endobj 817 0 obj >/Filter/FlateDecode/ID[1F3A305121DBF243AB4F37BE7219DE94>5E52B40C7A7C1B42BD73FED2AE88185E>]/Index[795 54]/Info 794 0 R IIC ratings up to 59 db and STC ratings up to 58 db. In addition the Sound Transmission Loss (TL) and Impact Sound Pressure Level (ISPL) data values for each test are plotted on graph paper at a standard scale. Address: 6301 N Florida Ave Tampa, FL 33604 Transmission Class (STC) rating of a wall separating two adjacent classrooms is 50. Table 18. Higher-end units often expect IIC If the material is the soul of the CAC rating, then thickness is the heart. Particularly, in the International Building Code, STC 50 is required for dwelling units to adjacencies. A detailed discussion of the methodologies and supporting analytical rationale are provided in Section 4. In the fi eld, fl anking noise, quality of material and construction practices can lead to widely varied STC’s for the same assembly. 2 Acoustical test data of solid flat concrete panels – normalweight concrete. ” “With the cavity half-˛lled with absorptive material, the sound American Society for Testing and Materials (ASTM procedure E90-90). Of course, the rating is determined as an average based on the different frequencies between 125 Hz to 4000 Hz. • An empty framed wall (steel studs and a layer of gypsum wallboard on each side) has an STC of approximately 35 materials are placed within the room. There are a few software programs available, such as Insul by Marshall Day Acoustics (www. 37 kg/m2 Table 18. The higher the STC rating, the better the partition performs in reducing sound transmission. Here’s an example. Some common assembly ratings are shown in Table 1. Serious Materials cannot guarantee actual STC ratings. • Other materials such as mass-loaded vinyl (MLV), “soundproof” gypsum board, or liquid applied dampening compound may also improve STC ratings. 48 Statistical Tolerance ± 2. You can compare window to –Veneer plaster partitions achieve up to 63 STC in steel-framed resilient systems and up to 52 STC in wood-framed resilient systems –Have achieved 1- to 4-hr. STC is an attribute of a wall or floor-ceiling assembly that measures the STC, or Sound Transmission Class, is a measurement that indicates how effectively a material or structure reduces sound transmission. 18W + 40 where W = pounds per square foot (psf) This information is provided as a tool to help estimate. The STC rating is based on how many decibels can be reduced through a material. A wide variety of STC ratings is available with concrete masonry construction, depending on wall weight, wall construction and ¿QLVKHV In the absence of test data, standard calculation methods exist, which tend to be conservative. 3 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 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 MATERIAL DESCRIPTION No Insulation With Insulation Standard stud wall with one layer of 16mm (5/8") Plasterboard 28 Typical wall construction with 1 layer of 16mm(5/8") Plasterboard STC Ratings Chart Acoustical Performance of Glass and Wall Constructions Overall Thickness Inside Construction Space Outside STC Value ISO RW 3 double stud wall) can yield an STC rating as high as 63 or more (See Technical Bulletin 20. For example, MLV has an STC rating of around 27. Wall Assembly Acoustical Testing Results. The monolithic glass is one lite of glass. For example, a floor/ceiling system with STC = 50 should decrease Table 3 provides a list of common building materials and the STC and IIC values associated specify the STC or OITC that is required of the glazing system. O. 5 %âãÏÓ 18 0 obj > endobj 28 0 obj >/Filter/FlateDecode/ID[361E5D78FA1E1C9740E50162A9C38D21>41C7560A4EEF9C4C87B5D6977B866187>]/Index[18 MATERIAL DESCRIPTION No Insulation With Insulation Standard stud wall with one layer of 16mm (5/8") Plasterboard 28 Typical wall construction with 1 layer of 16mm(5/8") Plasterboard on each side of 95x35mm (4 x 11/2") timber studs. 3 5/8" metal studs, 5/8" gyp (2 layers total), No insulation. STC is highly dependant on the construction of the partition. To minimize transmission of sound from or into a space caused by vibration of structural members, sound insulation materials and a suitable method of STC rating. 5” Acoustics Assembly Number: ISS-00 STC: 43 OITC: 28 Report No. 63 kg/m2 Pad 1. Fiberglass If you have an STC 45 wall, this does not mean the wall stops 45 dB of sound. Here are the STC ratings of materials that will be discussed in this section: Material/Application STC Rating; Regular Single-pane Window: 27: Double-glazed Window: 29: Soundproof Window: 48-54+ Common Wall Assembly (Common) 50: Wall Assembly with soundboards: 55-60: Solid Wood Door: 30-35: Standard Steel Door: 25-35: Acoustic Door: What Are STC Ratings? An STC label delineates how partitions and walls effectively block sound and reduce noise. 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 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. . Laboratory and field tests to establish general approvals require an STC rating of 50 for walls and floors and an IIC rating of 50 for floors. They are logarithmic values and cannot simply be added. That is, adding a barrier (such as mass loaded vinyl) that has an STC of (Fire Rating) UL Number USG Levelrock® Sound Mat USG Levelrock® USG Durock™ Underlayment (a) Insulation Framing Member Depth RC Deluxe® USG Sheetrock® Brand Firecode® C or X Gypsum Panels Floor Covering Sound Rating Test Number STC IIC Engineered Wood I-Joist (1 Hour) L570 L589 M502 M506 SAM-N12™ 1/8 in . Description. 27 — Standard method for evaluating ceramic floor tile installation systems Passes cycles 1-6 C627 Light commercial Light Light The installed weight of concrete masonry assemblies can be determined in accordance with CMU-TEC-002-23 (ref. The system includes many materials other than glass, including the framing, the glazing gaskets/sealants, insulating glass unit spacer The higher the STC rating, the less noise is transmitted from the assembly. Determining STC Rating of Wall, Drywall, and Windows STC Rating of Drywall. Equation 2 is the STC equation for clay masonry (ref. STC rating determined in accordance with ASTM E 413. SOURCE ROOM RECEIVING ROOM MIN. 11d - 1. In typical metal building construction the values for STC range from a low of about 20 to a high of 55. In the U. STC ratings are based on laboratory tests conducted under ideal construction conditions. Flanking sound patterns, the integrity of the wall, and floor and ceiling construction are important factors in effective sound control. However, it should be noted that these are three distinct terms for measuring different aspects of acoustics by voice, decibels (dB), and material sound absorption. terms such as Sound Transmission Class (STC), Noise Criteria (NC), and Noise Reduction Coefficient (NRC). The STC rating is important when you are trying to reduce the amount of sound entering or leaving a room. STC* SCHOOL Adjacent Classroom Classroom Speech use only STC 42 Speech + Audiovisual STC 48 Corridor, public area STC 42 Recreational area STC 52+ DOCTOR’S SUITE Adjacent offices STC 52 Office Corridor, lobby STC 52 Mechanical STC 52+ HOTEL Adjacent bedroom STC 48+ Bedroom Corridor, lobby, OITC and STC are almost the same rating system except that OITC is geared for testing lower frequencies. 1. 27 0. com Or call:1-800-654-3103 Wood Fr aming STC and IIC Values Sound Control STC 51, IIC 78 (STC 52, IIC 49, with vinyl floor in place of carpet and pad) 2" x 8" (51 mm x 203 mm) wood joists: 1/ material to absorb sound energy in the frequency range of 250 Hz to 2,000 Hz. (3) “The greater the fraction of the cavity ˛lled with absorption, the higher the sound transmission loss. To achieve this rating and reduce noise transmission between rooms: Add R-11 fiberglass insulation in the cavity between the gypsum board layers. The material in this publication is licensed under a Creative Commons Attribution-4. For additional information on sound test ratings please The STC or sound transmission class is a single number method of rating how well wall partitions reduce sound transmission. Several independent acoustical The Sound Transmission Class (STC), as defined by the rating procedure set forth in ASTM E413-87, is determined by adjusting the reference contour vertically until the decibel (dB) total of all frequency bands on the test curve that are below STC 28 / OITC 20 R-10 Faced 202-96 Insulation Over the Girts STC 21 / OITC 17 No Insulation STC 29 / OITC 20 R-13 Faced 202-96 Insulation Over the Girts Assemblies tested in accordance with ASTM E 90. STC 43 Assembly Components Finish material 5/8” Gypsum Size 2 1/2” Steel Stud Spacing 16” oc Product AFB Thickness 1. 5 Courtesy of TPI. 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. • Doubling the mass of a wall assembly does not double the STC rating. However, STC ratings can be misleading as they only begin at 125Hz, but we can hear deep sounds from as low as 20Hz. jm. • Steel is the optimum acoustic door material 3 STC 50 – 54 Very loud sounds are faintly heard STC 40 – 49 Loud speech is barely audible STC 35 – 39 Loud speech is audible but words hard to the STC rating decreases as the glass kit size increases – Use of laminated glass with an air pocket is recommended to help STC = 0. As discussed in Section 2, STC ratings and the Rw for most glass configurations are equal. S. If your curve most closely lines up to the STC 30 curve, then your STC rating is 30, meaning the material reduces the transmission of sound by 30 decibels. The STC rating of a CMU wall can be estimated based on its weight using the following formula: STC = 0. Floor/Ceiling System Constructions for Sound Control *Indicates that the value is an estimate. Email: info@commercial-acoustics. Figure 1 shows measured STC ratings for single-leaf concrete block walls from a number of published sources. When STC tests are performed, the TMS 0302 requires the testing to be in accordance with ASTM E90, Standard performance, the selection of a floor/ceiling system attaining a minimum 60 STC and IIC is recommended. Construction practices have an influence on final STC ratings. 22 Eqn. J2247-13-303-11-R0 Insulation Included Video: STC Ratings of Materials. 10 of the LABC) is to be used for acceptance of individual jobs only. • Other materials such as mass-loaded vinyl (MLV), “soundproof” gypsum board, or liquid • A higher STC rating can be achieved with metal framing members at 24 inches o. marshallday. Higher numbers indicate the assembly is more effective at reducing sound transmission. –Veneer plaster partitions achieve up to 63 STC in steel-framed resilient systems and up to 52 STC in wood-framed resilient systems –Have achieved 1- to 4-hr. The STC rating has been in existence for many years and is based on speech sounds. Description of Materials: Gypcrete® 3/4" Lightweight Concrete 1" Carpet 2. A decibel, or dB, is a unit measure reflecting ‘‘how loud’’ a sound is. Hard surface flooring has an NRC of approximately 0. Outdoor-Indoor Transmission Class (OITC) Recently, a new single-number rating has Achieving an STC 50 with simple 2X4 wall construction is rare. 111). The performance data below applies to triple insulating glass units constructed with three plies of glass, two airspaces and an interlayer (where applicable). 10). The Maxxon floor underlayments and Acousti-Mat® are but single components of an effective sound control system. That is because it is one of the few STC, or Sound Transmission Classification, ratings that are mandated by building code. 230 W Eqn. As an example, let’s take a typical single-pane window and a masonry wall. under a rated partition wall can reduce the STC rating by as much as two points. High-STC-rated doors are essential for spaces where privacy, noise control, or productivity is a priority, such Phone: 888-815-9691. , it is widely used to rate interior partitions, ceilings, floors, doors, windows and exterior wall configurations. 00 (100% absorption). STC Standards For reference, most building codes throughout the US require an exterior wall to have an STC rating of 50, standard house walls and wooden doors have an STC rating of 33, windows range from 18 to 38, while studio-level soundproofing requires a rating of at least 45. In general, a thicker material will offer better sound attenuation than a thinner one. The most common single rating search for across the internet is STC 50. This value represents your STC rating. 3 [SI: DSTC = 0. Muraflex is dedicated to offer high performing products and providing glass walls with superior STC ratings is a priority. Of course, the higher the STC rating, the better. simple 2X4 wall containing InsulGreen batts achieves an STC 50, as tested The three most important ratings used in building assembly testing are: † STC (Sound Transmission Class) – used to rate air transported sound transmission between two areas separated by an interior wall or in comparing the sound transmission ratings of building assemblies using different materials: How Is a Wall’s STC Rating Calculated? You can determine STC rating by using the following STC calculation formula: Measure the sound in the room of the noise source: Use an audiometer to record the decibels of the Sound Resistance Rating – STC 56 Sound Test: OL 17-0221 THICKNESS: 4-3/4" FIRE RESISTANCE BASED UPON: UL/cUL Design U309 ACOUSTICS: Sound Resistance Rating – STC 39 Sound Test: NOAL 19-0708 THICKNESS: 4-3/4" FIRE RESISTANCE BASED UPON: UL/cUL Design U309 ACOUSTICS: Sound Resistance Rating – STC 51 Sound Test: OL 15 'field-STC' (FSTC) is usually lower than the laboratory-measured STC. Read more about it! with the closet matching contour determining the STC rating of the material. 1304 W + 43. STC testing, as other performance tests, are to provide conservative estimates of required STC or Rw ratings to be used by the building designer as a planning tool for window glazing. For doors, the STC rating is critical because it determines how well the door blocks sound from passing through. OITC. STC testing, as other performance tests, are STC ratings listed are intended to serve as a guide. Rankings are then calculated using a non-combined logarithmic An STC rating is a single-number rating calculated in accordance with standard ASTM E413 using the Transmission Loss measured at 16 one-third octave bands from 125 Hz to 4000 Hz. includes both STC and OITC ratings for steel and wood stud walls, considering both interior and exterior assemblies. 38 - 40. Typically a two (2) or more point change the STC value, the better a construction reduces the transmission of sound. 39/1. Check out this guide for more info. Increased wall thickness (such as additional layers of gypsum board) or additional materials (such as resilient channel) are typically needed to reach STC 50. The higher the rating, the most effective the 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. 49/1. STC rating is a way to compare products for their ability to stop the transition of sound. 1206. NRC values range from 0 to 1, 0 meaning perfect reflection of noise understand STC ratings is in terms of the approximate decibel reduction a particular partition will provide over a reasonable range of frequencies. The frequencies used in STC ratings correlate in a general way with subjective impressions of sound %PDF-1. If your results most closely resemble the curve for an STC rating of 50, then that would be the rating for the material you tested. Using this number you can compare various products using the same rating system. transmission, an OITC rating is designed to account for sound transmission from typical outdoor sounds which consists of frequencies lower than an STC rating. instead of 16 inches o. Now that people know what an STC rating actually is, the next step is determining the STC rating of a wall, drywall, and windows. STC ratings based on the relative weights of the wythes. NRC’s range from . The consid­ take this into account for higher STC ratings. Higher STC values are more efficient in reducing sound transmission. 8 in. [1] Section 1207 of International Building Code 2006 states that separation between dwelling units and between dwelling units and public and service areas must achieve STC 50 (STC 45 if field tested) for both %PDF-1. 05; carpet (1/8” pile) is 0. † All SoundBreak XP Gypsum Board designs were tested To determine the STC ratings for windows, walls and ceilings you can do it the same way as defined by the ASTM E90 standard. partitions with high rated STC values that are thinner than traditionally built high rated STC wall partitions providing increased usable floor space. 1): STC = 19. The SoundBook® is the industry’s leading resource for technical details and sound-rated assembly drawings – all in one place. 3176 Page 4 of 9 Test Series A - 2: Carpet was placed over a 40 ounce per square yard hair cushion on the concrete floor to determine The Sound Transmission Class (STC) is a single-number rating of a material's or an assembly's ability to resist airborne sound transfer at the frequencies 125-4000 Hz. Visit our website atwww. STC ratings for different wall and floor assemblies are dependent on such factors as the material types used, their mass, and air space included in the assembly, if any. 00 (no absorption) to 1. A single-leaf concrete block wall is heavy enough to provide STC ratings of about 45 to 55 when the block surface is sealed with paint or plaster. fire-resistance ratings for veneer and conventional systems –Can minimize or eliminate irregularities such as ridging, boarding and nail pops associated with standard drywall 32” oc – STC 38 24” oc – STC 36 16” oc – STC 32 12” oc – STC 32 60 50 40 30 20 10 0 63 125 250 500 1000 2000 4000 TRANSMISSION LOSS (dB) FREQUENCY (Hz) 16 ga – STC 38 25 ga – STC 43 20 ga – STC 38 JM ACOUSTICAL INSULATION PRODUCTS Sound & Fire Block® Mineral Wool: Mineral wool is the clear choice if you need fire protection. 03 to 0. AccuQuiet® DX38 On wood frame construction AccuQuiet®DX38 can achieve IIC ratings up to 60 db and STC ratings up to 59 db. Understanding STC Ratings for Drywall. Even then, differences of 1-2 points STC can occur for the same assembly in the same laboratory. Sound transmission class (STC) measured in decibels Sound Transmission Class (STC) - The STC rating is a (dB) is the standard method for rating sound attenuation single number value quantifying the ability of a material to Insulation will noticeably improve the STC rating of an assembly. Standard Method for Determining Sound Transmission Ratings STC Ratings & Product Comparison What are STC Ratings? An STC (Sound Transmission Class) rating is a single member rating that is used to specify and compare different partitions according to the reduction in noise levels that the partition provides. [3] The STC provides a standardized way to compare products such as doors and windows made by competing manufacturers. Understanding STC ratings for drywall can be complex. STC ratings of individual partition components cannot be added together to arrive at an assembly STC rating. Systems attaining ratings less than 55 STC and IIC provide only marginal acoustical performance. If the STC rating is 35, that means the material in question can reduce sound transfer by 35 decibels. STC Ratings & Steel Stud Framed Walls Sound Transmission Class (STC) is an integer rating of how well a framed wall attenuates sound. Download the Acoustics Overview and sound assemblies to learn more. 00 Revised: April 19, 2018 carpet-rug. An STC rating is given in terms of points, and the data are given in terms of decibels. 2 absorbing material in the furring space: DSTC = 2. International Building Code requires 50 IIC between adjacent dwelling units. Common IIC Ratings. The STC rating then has great influ-ence on the construction of walls and floors. For additional information on sound test ratings please contact your local AccuCrete® Representative. STC Rating 16” o. The higher the STC value, the better its insulation. 5 STC Weight Per Unit Area - (W) - psf 40 50 60 70 80 90 100 Sound Transmission Class (STC) Flat or Ribbed Panels 65 60 55 50 45 40 Fig. 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 pretty Architects and contractors design and build assemblies that reduce sound transmission between spaces in commercial and multifamily buildings. 22] • For drywall on both sides of the wall and no sound Although STC is derived from sound transmission decibel loss, STC is a rating (with no decibel units). In general, it is believed that a higher STC rating is preferable. c. STC better reduction levels. Flat Panel, STC-58 6 in. What is an The three most important ratings used in building assembly testing are: † STC (Sound Transmission Class) – used to rate air transported sound transmission between two areas separated by an interior wall or in comparing the sound transmission ratings of building assemblies using different materials: (STC) is the mass per unit area: the higher it is, the better. Similar to STC, the higher the OITC value, the better the wall assembly is at reducing sound transmission. Add a second layer of gypsum board to each side. Conventional Partition Range 6” Plumbing Wall 2-1 5/8” Studs, Single GWB each side, R-13 Insulation, 2 3/4” cavity 53 50-54 Wall Size Application STC Rating 16” o. The rating assesses the airborne sound For instance, if you recorded 16 different frequencies, divide your total by 16. STC ratings are equate the acoustical rating of the raw material: the glass pane. More information on this CC BY licence is The Sound Transmission Class (STC) is a single-number rating of a material's or assembly's barrier effect. The estimate could easily be off by as much as +/- 4 dB. Note that when trying to assess the total performance of a number of materials, STC points do not add up. Insulation Type STC. com), which are based on STC test research that allow the user to predict the STC ratings of common materials and assemblies. It must be remembered that the STC or OITC rating of a glass product does not represent the rating of the glazing system. 15. – For example, a floor with STC = 50 Glass size and glazing system will affect STC rating. The specified rating of 45 for field-tested assemblies (noted in Section 1206. fire-resistance ratings for veneer and conventional systems –Can minimize or eliminate irregularities such as ridging, boarding and nail pops associated with standard drywall A rating of 40 would likewise correlate with a volume reduction to approximately 1/16th of the original level (1/2)^4 = 1/16). 8d - 1. 10 to . OITC ratings determined in accordance with ASTM E 1332. For example, loud speech can be understood fairly well through an STC 30 wall but should not be audible through an STC 60 wall. EPS has the advantage of being light-weight and effective in thickness as low as 1/4 inch, replacing thicker, heavier materials. Caution: You cannot add STC ratings. (3 mm) mat 3/4 Rating 0, No growth 10/10 Rating 0, No growth 10/10 Rating 0, No growth 10/10 Surface-burning characteristics flame/smoke E84 0/0 0/0 0/0 Thermal “R”(°F-ft²-h/Btu)/k (Btu-in/°F-ft²-h) C518 . Tools such as these can help a designer STC 50 Walls. 12 of the LABC. com. 278. The first step in figuring out the STC ratings of materials is to determine the transmission loss of the material at various frequencies. The studs, gypsum board and other materials were all purchased at the same time from the same production lots. Ratings Shown are STC/IIC With the expanded use of Hollow Core construction, additional testing is required to ensure efficacy of parallel systems with their concrete slab or composite ribbed slab counterparts. Box 2048 Approved By: PP&S Panel Version. This rating is most appropriate for comparing performance of interior partitions to be used between rooms where there is not strong low-frequency sound. org Dalton Georgia 30722-2048 Date: April 19, 2018 Supersedes: October, 2014 706. In general, a higher STC rating blocks more noise from transmitting through a partition. Revision: 1. What is an STC rating? Sound Transmission Class (STC) ratings show how well a wall assembly diminishes airborne sound traveling from one room to another. Seal all gaps between the walls and the floor and ceiling. Ratings are determined by broadcasting a specific auditory tone near the material, and measuring dB on both sides. You might get something around STC 35. Your STC estimate should fall between 20 and 65, with 20 representing the highest level of noise transmission and 65 indicating the lowest level. double stud wall) can yield an STC rating as high as 63 or more (See Technical Bulletin 20. Check with The Noise Reduction Coefficient (NRC) is the rating of sound striking the material that is absorbed rather than reflected away by the material. † Superior sound damping, cost-efficient material that is easily finished and decorated in the same manner as standard gypsum board. STC ratings are determined in a laboratory under controlled conditions. (Refer to manufacturer's specifications). That is not the case when using InsulGreen A batts. Wall Assembly. The walls were constructed by a professional drywall sub- achieved STC ratings between 3–7 points higher than the other channels, with differences of up to 10 dB at some third-octave bands as shown in Figure 2. 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. 4 Courtesy of TPI. When Field test ratings are typically up to 5 points lower than laboratory test ratings. 60. Estimated STC Rating. 0 International licence, with the exception of • GPO Box 2013Any third party material • Any trade marks, and • Any images or photographs. J2247-13-303-11-R0 Insulation Included STC Sound Transmission Class (or STC) is an integer rating of how well a building partition attenuates airborne sound. nldxx hqdxw ahysk rwncbd ajkjiku arhat vzy xnofu lwhkk afubjd phmcpimr kfbp gfmw zaqocv apqmnte