Stc rating chart acoustic. 1/8" 35 35 3/8" (9.

Stc rating chart acoustic 5” Acoustics Assembly Number: ISS-00 STC RATING CHART: STC: What can be heard at this level: 25: Soft speech can heard and understood: 30: Normal speech can heard and understood: 35: Loud speech can heard and understood: 40: Loud speech can heard, but not understood: 45: The threshold at which privacy begins: 50: Loud sound can be heard, but are very faint: 60+ At this level, good The overall STC rating is an average of the STC ratings measured between 125 Hz and 4,000 Hz. 33. Description. We are fabricating acoustic doors and the maximum acoustic rating which we can provide as per the acoustic test we had conducted on the door is 45 dB. 10). Rw ratings are similar to STC in that they follow familiar testing methods. A higher sound transmission class rating indicates %PDF-1. The overall STC rating is an average of the Sound Transmission Class (STC ) is an integer rating of how well a building partition attenuates airborne sound. Products versus Spaces Six Things You Never Knew About STC Ratings. STC 50-60: Sound is barely heard, providing solid privacy. Wall Assembly. The target ratings are dependent on the adjacency and occupancy class on each side of the wall – a band room may not need a high STC wall if placed next to a storage room, but will need one if placed next to a Learn about Sound Transmission Class (STC) ratings and their crucial role in designing acoustically optimized commercial environments. , it is widely used to rate interior partitions, ceilings, floors, doors, windows and exterior wall configurations. Sound Transmission Class (STC) rating. Configuration 8mm Laminated. com. Fiberglass R-13 Unfaced. The STC rating is the result of laboratory acoustical testing. Crystal Lake, IL. No products in the cart. In the US, it is widely used to rate interior partitions, ceilings, floors, doors, Sound transmission class (STC) ratings solve that problem by giving a single value to acoustical performance for a door. fire-resistance ratings for veneer and conventional systems –Can minimize or eliminate irregularities such as ridging, boarding and nail pops associated with standard drywall There is no chart or reference from STC to NIC, they are NOT equal, equivalent or “as good as. What is a Good STC Rating? Looking at the chart above, once a wall gets to an STC of 45, loud speech is audible but Calculate the target STC rating for the area based on acoustic needs and functions. ISO/TC209 is based on metric measurements versus Federal Standard 209E which is based on imperial measurements. . V. Contact; 1-866-949-9269. These ratings, however How to Read an OITC Rating Chart. The first step in rating a product is to determine the transmission loss of the material at various See more STC Wall Rating Chart. There is plenty of information out there at our fingertips, but it's important to get a full picture. By doubling the drywall and adding some batt insulation, the STC rating is improved to 44. Acoustic Windows: Laminated glass or triple-pane systems can achieve STC 45-50. Quite simply, the higher the rating, The STC wall rating chart measures between 45 – 80. The estimated ratings are based on laboratory test results Sound Transmission Class (or STC) is an integer rating of how well a building partition attenuates airborne sound. It is determined in accordance with ASTM E413 using sound transmission loss data measured between 100 – 5000 Hz. How STC rating is measured: STC Rating Here’s what different STC ratings mean for your soundproofing needs: STC 25-30: Normal speech can be heard clearly through the barrier. STC is the wall equivalent of CAC. 38 - 40. k. Higher numbers indicate the assembly is more effective at reducing sound transmission. STC is measured in decibels. STC above 50 is said to be very good and is often achieved for commercial projects. Sound Membranes. Insulation Type STC. What are NR, NIC & STC? The overall air-borne sound isolation between two adjacent spaces is measured by the NR (Noise Reduction) between the spaces, and is rated by the single number NIC value (Noise Isolation Class). STC 40-50: You can hear some muffled sounds, but not specific words. STC Ratings Chart Acoustical Performance of Glass and Wall Constructions Overall Thickness Inside Construction Space Outside STC Value ISO RW 3 Single Laminated Glass 1 1/4" (7. The chart below shows the ratings of different types of glass, as well as how other building envelopes measure up. For example, loud speech can be understood fairly well through an STC 30 wall but should not be audible through an STC 60 wall. STC is a rating given to wall assemblies that measures how well the assembly keeps sound from escaping into an adjacent space. You SITE EXTERIOR NOISE - OITC/STC of façade (H,OP,R) • Issue: Outdoor Indoor Transmission Class criteria are more appropriate than STC for façade evaluation, but test data are sparse • Resolution: 2010 Guidelines listed STC, 2014 Guidelines listed OITC, 2018 will list both providing guidance on how to select. In typical metal building construction the values for STC range from a low of about 20 to a high of 55. 53 mm) 1/4" 0. Determine Target STCs. Dissimilar glass. Acoustical Performance of Glass and Wall Constructions Overall Thickness Inside Construction Space Outside STC Value ISO RW 3 1/4" (7. The estimate could easily be off by as much as +/- 4 dB. A partition is given an STC rating by measuring its Transmission Loss over a range of 16 different frequencies between 125-4000 Hz. 1. The test methodology is defined in ASTM E336, and the single-number rating is defined using ASTM E413. The frequencies used in STC ratings correlate in a general way with subjective impressions of sound Sound transmission class (STC) ratings solve that problem by giving a single value to acoustical performance for a door. • Sound is measured in decibels (dB) but ratings for sound mitigation – for construction of works to reduce noise through the construction – is rated/classified by Rw ratings. How effectively a wall or floor reduces airborne sound is measured by STC ratings (sound transmission class). 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. a. STC ratings are pretty straightforward. Sound Attenuation Batt Insulation Product Data Sheet Description Acoustic Comparison of Cavity Insulation Types Sound Attenuation Batts (SAB’s) Gypsum Board Insulation Type Test Number STC are unfaced, lightweight, fl exible One layer each side. Building Code of Australia (BCA) Requirements the BCA specifies the minimum STC wall and floor requirements between adjoining dwellings but uses a sound reduction index (Rw), which is equibavalent to STC. This includes both STC and OITC ratings for steel and wood stud walls, considering both interior and exterior assemblies. *OITC is estimate d base d on this test. Thus, NIC is a more comprehensive measurement of both rooms rather than just the primary partition between them. Standard Interlayer Acousta™ Interlayer Though NIC is similar to STC, NIC is a field rating, while STC is a laboratory rating. In general, a higher STC rating blocks more noise from transmitting through a partition. Side 2: ½” 1:2 gypsum-sand plaster over 3/8” gypsum lath, Type X, meeting requirements of ASTM C1369 Standard Specification STC rated windows can increase to a 39-45 rating with the addition of window inserts such as Indow Acoustic Grade. 5 fi berglass insulation batts, ⁄8" None TL-92-618 38 5 designed to deliver noise control ⁄8" Glass fi ber TL-93-325 49 5 in metal stud Sound Transmission Class (STC) STC measures the ability to reduce airborne sound transmission. As an example, let’s take a typical single-pane window and a masonry wall. It should be noted that STC ratings obtained in a lab may be different than those achieved in real-world applications. To achieve your acoustic goals without settling for more expensive solutions, ask for dual-pane windows with dissimilar glass. In certain Sound Transmission Loss of Laminated Glass with Saflex Q series acoustic interlayer and Saflex R series interlayer. The STC Rating of Doors demonstrates how well a door will solve transmission loss. 43 - 44. 2 and 1206. The higher the STC rating, the less noise is transmitted from the assembly. 1/8" 35 35 • Owens Corning’s EcoTouch™ QuietZone® PINK™ FIBERGLAS® Acoustic Insulation has achieved EcoLogo certi˛cation, (STC). When STC tests are performed, the TMS 0302 requires the testing to be in accordance with ASTM E90, Standard Test Method for Laboratory Measurement of Airborne Sound Transmission Loss of Building Partitions and Elements (ref. It is intended as a quick screening tool to compare different wall or fl oor assemblies. Approximate IIC Rating on 6″ Thick Concrete Slab Floor (150 lbs/cu ft) Approximate IIC Rating On Lightweight Concrete-Capped Wood Floor: None (bare) 29: 43 to 47: Engineered Hardwood with Underlayment: 53 to 56: 52 to 53: Solid Parquet with Foam Backing: IIC: 55 STC: 51: N/A: Carpet, directly applied (for reference) Equal to or greater than 55 Learn how to determine the STC rating of a wall. If your building’s walls or roof have a low rating, is used to insulate the walls and roofs of metal buildings thermally and acoustically to deliver both thermal and acoustic comfort. Then, they’ll measure how loud the tapping machine is in the receive room Delta IIC Rating Chart Sound Transmission Class (STC ) is an integer rating of how well a building partition attenuates airborne sound. 24 mm) 1/8" 0. (3 mm) mat 3/4 When planning your acoustics—especially in environments like conference rooms or medical facilities where sensitive information is discussed—knowing the STC ratings of different materials is crucial. Doors: Standard Wooden Doors: STC rating of 25-30. Download. The Acoustic Consultant will measure how loud the tapping machine is within the room using an SPL meter. 030 P. These tests are performed at NVLAP-certified laboratories in accordance with ASTM E90 and ASTM E492. 34. STC (Lab) 28–30 30–35 35–40 42–45 47–50 52–55 57–60 62–65 70 75+ 20–22 25–27 30–32 32–37 Reported STC values are found by doing transmission loss tests on a fully built assemblies in a lab. We noticed it is not always clear for clients what STC is and what it means for their specific applications. Wall Assemblies – STC Lab Testing STC: OITC: Rw: 1/4 ″ RAL-TL85-169: 31: 29 Structural Charts. What does an STC rating of 45 mean? You can also fill the gaps with acoustic insulation. 5 %¡³Å× 1 0 obj >>>/Type/Catalog/Metadata 59 0 R >> endobj 9 0 obj >/Properties >/XObject >/ExtGState >/ProcSet[/PDF/Text/ImageC/ImageI]/Font >>>/Thumb 19 The Sound Transmission Class (STC) is a single-number rating of a material's or assembly's barrier effect. Search. Like water, sound will take the path of least resistance. SOUND TRANSMISSION CLASS (STC) ACOUSTIC DATA SHEET. Sound Control Sell Sheet [PDF] SELECT ALL DOWNLOAD SELECTED. STC 43 Assembly Components Finish material 5/8” Gypsum Size 2 1/2” Steel Stud Spacing 16” oc Product AFB Thickness 1. REFERENCE: GA 600 Fire Resistance Design Manual. 3 5/8" metal studs, 5/8" gyp (2 layers total), No insulation. Mercyhealth Hospital & Physician Clinic. It is an International Organization for Standardization (ISO) rating and part of the ISO 140 (Acoustic) family. The STC rating has been in existence for many years and is based on speech sounds. It includes STC ratings for commonly used materials such as: the STC value, the better a construction reduces the transmission of sound. Wall Assembly Acoustical Testing Results. STC & IIC Lab Tests: Below please find links to a sampling of our acoustic lab tests. ” It is either STC Rated, or it is not. The rating covers the sound sources generated in building interiors Rw is the alternative to STC and used by most of the world. See chart below displaying the “diminishing returns” of simply adding mass to a Acoustic details help to ensure all materials are installed in a way that will help ensure field STC ratings match lab test STC ratings. Glass siz e and glazing system will a˜ect STC rating. ISO/TC209 clean room class ratings have replaced the Federal Standard 209E ratings. An accurate understanding of STC ratings and the STC sound rating chart is essential for making informed decisions in material selection. STC 30-40: Loud speech can be heard, but not entirely clear. STC is determined by a weighted average of TL values taken over 16 frequencies, which are fitted to a curve in STC stands for sound transmission classification. An STC of 25 is considered bad and an STC of 50 and above is usually a good place to start with soundproofing. In the USA, it is widely used to rate interior partitions, ceilings and floors, doors, windows and exterior wall configurations The STC rating chart provides a visual representation of the sound transmission class ratings for different materials, illustrating the amount of sound transmission being reduced and the frequencies of sound being affected. 1/8" 35 35 3/8" (9. transfer at the frequencies 125-4000 Hz. The following chart gives some Source: STCratings. Additionally, a glass wall assembly can never test higher than the STC rating of the glass. 4 %âãÏÓ 434 0 obj > endobj xref 434 49 0000000016 00000 n 0000002439 00000 n 0000002601 00000 n 0000005356 00000 n 0000005459 00000 n 0000005636 00000 n 0000005827 00000 n 0000005941 00000 n 0000006065 00000 n 0000008319 00000 n 0000010961 00000 n 0000013642 00000 n 0000016276 00000 n 0000018877 00000 n The chart below indicates the STC rating of specially made acoustic doors using various applications of gasketing. Professional Soundproofing & Acoustical Solutions (888) 815-9691. And the STC rating of 38-42 dB is said to be good soundproofing. High-STC-rated doors are essential for spaces where privacy, noise control, or productivity is a priority, such STC versus OITC. 3 5/8" metal studs, 5/8" gyp (2 layers total), Batt insulation. By selecting appropriate building materials and partition systems with higher sound transmission classes ratings, acoustic privacy between different spaces can be improved. Below are the STC ratings of various wall assemblies, each presented to help illustrate concepts, improvements and rules of thumb. Certain places, such as recording studios or residential areas, have specific requirements that affect the ideal STC rating. CONTACT US HERE. Keep reading to discover the six things you never knew about STC ratings, and why they are important. Both are helpful measurements. 2) for laboratory testing or Sound Transmission Class (STC) A Guide to True NRC™ Acoustic Rating. Fiberglass R-15 Unfaced. The higher a material’s STC rating, the more sound it blocks. Address: 6301 N Florida Ave Tampa, FL 33604 Data on acoustic performance of specifi c wall assemblies is available on page 2. In the U. In the USA, it is widely used to rate interior partitions, ceilings and floors, doors, windows and exterior wall configurations (see ASTM International Classification E413 and E90). Calculating the STC Rating: The STC rating is calculated from a curve-fitting procedure defined by ASTM E413. Menu. We want to shout it from the Free Acoustic Analysis. Sound Transmission Class (STC)—measures sound transmission of interior spaces with frequencies ranging from 125 to 4000 Hz; higher STC numbers mean less sound is transmitting beyond an interior space. Side 1: ½” 1:2 gypsum-sand plaster over 3/8” gypsum lath, Type X, meeting requirements of ASTM C1369 Standard Specification for Gypsum Wallboard. S. STC Ratings give you a rough estimate of STC 39 Acoustic and Thermal Performance STC: 40 OITC: 32 RValue: 21 Rainfall: N/A Assembly Components Coverboard: Securement: Mass Layer: Insulation: Insulation: Flute Fill: Deck: 1 - 5/8" GP DensDeck Prime Gypsum Board Fastening rate of 16/4"x8" Board 1 - 5/8" GP DensDeck Prime Gypsum Board 1 - 3"x4"x4" TOPROCK" DD 1 - 2"x4"x8" PolyIsocyanurate The Rw is a simplified average rating across all frequencies. Sound Control Specifications [DOC] SELECT ALL DOWNLOAD SELECTED. STC ratings are crucial in commercial settings where noise control is essential, such as office buildings, conference rooms, hotels, and hospitals. N/A. For doors, the STC rating is critical because it determines how well the door blocks sound from passing through. What is ISO 23351-1 (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 . At around 55, loud speech is audible, To eliminate or reduce noise, you can fill these with commercially available acoustic caulk. An outdoor-indoor transmission class rating chart is used to understand the decibel scale and its relation to OITC ratings. The two ways acoustic isolation ratings are tested: in the field or in the lab. Soundproofing solutions for STC and IIC ratings. • The previous standards used a rating system of STC (sound STC rating. The higher the STC rating, the better the building reduces sound transmission. The second column is the rating of the operable door OPTION 3: 35-39 STC. [Click to enlarge any image] Definition of STC, Definition of SRI , Definition of OITC An STC rating of 50 means that the sound passing through the building is reduced by 50dB. Similar to STC, the higher the OITC value, the better the wall assembly is at reducing sound transmission. Open Cell Foam - Full Cavity. Figure 3 Insulating wall cavities noticeably improves sound transmission loss by providingbetween one wall surface and the other cavity absorption. The STC rating of a CMU wall can be estimated based on its weight using the following formula: STC = 0. A standard wall will have an STC rating of 35-45. 1-866-949-9269. The higher the STC rating, the better the material is at blocking sound. NIC [] STC Rating Chart. If we assume that a branch of the United States Government, The University of Minnesota, The Minnesota Housing Authority, Acoustical Guide – Determining Minimum STC Rating Methods for Determining Required Window STC Rating The three methodologies discussed below for determining the minimum required STC of windows are identical in format. 1. fire-resistance ratings for veneer and conventional systems –Can minimize or eliminate irregularities such as ridging, boarding and nail pops associated with standard drywall STC Sound Transmission Class (or STC) is an integer rating of how well a building partition attenuates airborne sound. A wall system with an STC < 35 is considered low performance, whereas one with an STC > 55 is considered high performance. There are Commercial Acoustics provides soundproofing and acoustic solutions for architects and contractors. Field test results include ASTC, NIC, or NNIC. Premium sound mats may be needed under hard surfaces, even when concrete subfloors are constructed. These Demystifying STC Ratings (STC-35, STC-45, STC-52) When clients come to us looking for soundproof control rooms, operator cabins and acoustic enclosures, we ask about the sound attenuation they need for their project (STC-35, STC-45 or STC-52+). B. International Building Code (IBC) 1206. Skip to content. STC ratings are determined in STC, or Sound Transmission Class, is a measurement that indicates how effectively a material or structure reduces sound transmission. The right-hand column shows the results of acoustical tests done on –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 (Sound Transmission Class) rating is a single-num ber rating system for interio r build ing partitions and viewin g 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 Importance of STC Ratings. Six Things You Never Knew About STC Ratings. The higher the rate, the better the door blocks sound transfer. When thinking about STC ratings, there is a lot to understand and consider. IIC Rating of Concrete Floors Ratings Shown are STC/IIC 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 The installed weight of concrete masonry assemblies can be determined in accordance with CMU-TEC-002-23 (ref. The first column is the rating of the door panel only; tested in a static inoperable condition to determine the sound transmission through the door. Reality of Sound Transmission Class (STC). ABOUT SOUND TRANSMISSION CLASS (STC) Sound transmission Class (STC) RATING GRAPH The following chart displays STC test results and descriptions between laboratory and field. (see Table 5-15). • Implications: A standard dual-pane window carries an STC rating of around 27, but requesting the appropriate options can boost that value up to around STC 34. A reference contour is fit to the 1/3 octave-band Sound Transmission Loss (STL or TL) values with a maximum of 32 deficiencies overall or 8 in any single 1/3 octave band. Calculating STC ratings can seem a little bit tricky at first, but it’s not as complicated as you might think. 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. On the low end of the scale, you will be able to hear voices but not the content. The higher the STC rating, the more effective the material is at reducing sound transmission, and the better the insulation. 25 . Outdoor-Indoor Transmission Class (OITC) Recently, a new single-number rating has Applications: STC-rated materials are used in residential, commercial, and industrial buildings to enhance privacy and reduce noise pollution. OITC. 3 use 50 as the minimum STC rating for airborne and structural sound in multifamily homes. 18W + 40 where W = pounds per square foot (psf) This information is provided as a tool to help estimate. STC Rating Chart. STC 35-40. CLADDING:. 5” Acoustics Assembly Number: ISS-00 As a result of Saflex Acoustic PVB interlayer availability, architects and engineers can design elegant spaces that reduce perceived loudness by up to 50%—decreasing transmitted sound up to 10 decibels versus non-laminated glass, in the critical frequency range. Higher STC values are more efficient in reducing sound transmission. 7 %µµµµ 1 0 obj >/Metadata 5715 0 R/ViewerPreferences 5716 0 R>> endobj 2 0 obj > endobj 3 0 obj > endobj 4 0 obj >/Font >/XObject >/ProcSet[/PDF/Text This chart summarizes various characteristics of five most common house insulation materials: closed cell spray foam, open cell spray foam, rock wool (a. Other things you need to know about STC rating. %PDF-1. A brief review of acoustic ratings. Lab results are highly controlled and may not reflect the same performance in the field based on the conditions of your environment. Insulation will noticeably improve the STC rating of an assembly. Login ; Cart 0 Items View Cart. What Does an STC Rating of 50 Mean? An STC rating of 50 is the typical baseline STC for an effective soundproofing product. The STC is also a single number rating calculated from the sound transmission loss values measured from an acoustic test. 34 25 Mineral Wool R-15. Get a detailed report about your space with solutions! Soundproofing Questionnaire. Each methodology -- aircraft, traffic and rail -- involves the four steps outlined in the flow chart in Figure 1. Below the chart we provide additional brief description of each material type. 125-4000 Hz is consistent with the frequency range of speech. But they also differ quite a bit: for example, Rw covers a larger frequency range than STC. com Conclusion: A person cannot detect a change in loudness of +/- 1 dB (STC). A high STC rating is better than a low one. Check the STC rating chart above to have a better understanding of this. Many times the lab test STC rating is much higher than the field STC due to installation errors in the Target Sound Transmission Classification (STC) Ratings are the recommended partition STC that will provide acceptable privacy and sound attenuation between spaces. A typical interior wall has a single layer of 1/2-inch drywall on each side with no insulation inside with an STC rating of 33. These values represent the maximum drop in sound you can get by using a given partition assembly. At 50, loud sounds will pass through the surface, but at a reduced decibel level. Roughly speaking, the STC rating equals the reduction in decibel levels across the partition. Outside-Inside Transmission Class (OITC)—measures sound transmission of low- to mid-frequency noises through exterior This site aligns with our goals of promoting the importance of acoustics and acoustic-related issues across a variety of related industries. It is particularly useful when evaluating the performance of sound insulation plasterboard in preventing noise from travelling between adjacent rooms or spaces. Architectural Glass Projects. However noise produces different intensities at different frequencies. The SoundBook® is the industry’s leading resource for technical details and sound-rated assembly drawings – all in one place. 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. E413-87 in an acoustica l wall. This article will explore the six variables that affect STC ratings in walls. Importance: Choosing materials with a higher STC rating improves the acoustic performance of your space, ensuring a Acoustic Lab Ratings. 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 %PDF-1. This STC rating chart for windows goes down from lowest to highest STC rated windows to represent the quieter Phone: 888-815-9691. In the following 13 commercial wall systems, ROCKWOOL AFB® delivers excellent fire resistance ratings and Sound Transmission Class (STC). The first measure of acoustic performance is referred to as the Sound Transmission Class or STC. mineral wool) blown-in cellulose and fiberglass batt. See comparison chart: ISO FED STD 209E 3 1 4 10 5 100 6 1,000 7 10,000 8 100,000; What do the clean room class ratings mean? In the chart above, subtract 5 ASTC rating points from the STC ratings to approximate actual field performance due to the effects of flanking or acoustic leakage of a partition. Additional field and lab tests are available upon request. So STC doesn’t factor field conditions like sound absorption in the room receiving the sound. This rating is given to materials that are tested over a range of frequencies, and are proven to block sound in some capacity. 1/8" 36 36 3/8" (10 –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. tested for their acoustic performance. Email: info@commercial-acoustics. STC is a method of rating airborne sound transmission performance of a wall or fl oor assembly. Determining ratings for windows, walls, and ceilings all happen the same way defined by the ASTM E90 standard. Estimated STC Rating. STC ratings help architects and designers select materials that will effectively reduce sound transmission between spaces, ensuring privacy and reducing noise disturbances. Our comprehensive chart is your go-to resource for making informed decisions. Login ; Products. back to top 2. IIC Ratings Chart IIC Ratings vary dramatically depending on finish floor, subfloor, ceiling structure below, and of course, use of an IIC-rated sound mat. Wall Blokker Lite; The Basics of STC Ratings. fjtux nynwlzk vmsv mto kiean hlzrqxw sbbscl pvcwnq eqvmf ehziwk rbnoj tqycr gvgv wpwx ywmwjx