Stc rating wall assemblies. WORKS FOR INTERIOR PROJECTS.

Stc rating wall assemblies Similar to STC, the higher the OITC value, the The U. This is ideal to use in a factory to sperate office space from loud manufacturing areas. Revit, CAD, and construction details for fire rated wall assemblies can be downloaded for planning and material estimation. Bullet & Forced Entry. STC 43 Assembly Components 16 ROCKWOOL Acoustic Wall Assemblies Catalog ROCKWOOL Acoustic Wall Assemblies Catalog 17 STC 50 Assembly Components Finish material 1/2” gypsum, 2x 1/2” gypsum on single side The SoundBook® is the industry’s leading resource for technical details and sound-rated assembly drawings – all in one place. 5 STC values are logarithmic values and cannot simply be added. REFERENCE: USG SA-100 Fire Resistive Assemblies. Side 1: 5/8” Gypsum wallboard, Type X, meeting requirements of ASTM C1369 Standard Specification for Gypsum Wallboard. Insulation Type STC. STC STC STC STC STC STC. Stud Spacing 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. The higher the STC rating, the better the material or assembly is at reducing noise. Department of Housing and Urban Development offers resources and information on housing programs, policies, and assistance for individuals and communities. Similar to STC, the higher the OITC value, the better the wall assembly is at reducing sound transmission. 1 15-1. (STC). Fire Rating: 1 hours: System STC: 53 System Thickness: 7. Acceptable Solutions. PDF. Any partial or total reproduction of this information without consent is unauthorized˜ 3315 E Division St Arlington, TX 76011 Phone: (817) 640-4900 www. Revit PDF. 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 not understandable. Accessories. 27 Feb. So, whether you’re building a new home or renovating an office, knowing your STC rating is crucial for achieving the right level of soundproofing. Penetrations Through Rated Wall and Floor Assemblies. Author: Myers, Beverlee A. High STCs may also be achieved by using a vinyl barrier (such as mass loaded vinyl) in the wall to improve soundproofing performance, especially with metal stud wall assemblies. com Browse Similar Articles. WS4-1. For example, loud speech can be understood fairly well through an STC 30 wall but should not be audible through an STC 60 wall. to confine and isolate fire within a zone comprised of fire resistance-rated walls, ceiling and floor assemblies. 82 KB PDF) but STC should not be misconstrued as an exact measure of the number of decibels of sound an assembly can stop. Understanding STC Ratings for Drywall. Determine Target STCs. Product Features. Assemblies. Standard Amvic ICF Interior Wall2 Amvic ICF Please consult the actual fire resistance directory or test report for complete information. All USG 1- and 2-hour rated floor assemblies are designed to meet the current International Building Code (IBC) and feature USG Levelrock® Brand and USG Durock™ Brand underlayments and USG Levelrock® sound attenuation products. General Information. 33 25 Closed Cell Foam - Full 16 USG Acoustical Assemblies Partitions Steel Framed A Non-loadbearing Acoustical Performance Fire Performance Reference Construction Detail Description STC Test Number Rating Test Number ARL Index wt. unblocked joist First, select the hourly rating needed; Second, choose the type of design you are seeking (example – Walls/Partitions (steel framed), Floor/Ceiling (wood framed), etc. Mass: An extra layer of gypsum board on one or both sides of a wall assembly will increase the STC rating. com Page 7 of 7 AN: 22. 18W + 40 where W = pounds per square foot (psf) This information is provided as a tool to help estimate. Consensus on MLV and Soundproofing Membranes: Ultimately, Mass-Loaded Vinyl and other soundproofing membranes can be most effective when used in tested assemblies where STC performance is critical. ID: 1024. The estimate STC Ratings for Various Wall Assemblies Home. The 1-800-NATIONAL ® Construction Services team, construction design managers and field sales representatives answered a wide variety of questions from architects, contractors, installers, dealers and specifiers in 2024. Skip to content 813-980-1400 Call Us! | sales@acoustiblok. 34 25 Mineral Wool R-15. Any products manufactured by persons other than Georgia-Pacific Gypsum are presented for illustration only. STC 43 Assembly Components 16 ROCKWOOL Acoustic Wall Assemblies Catalog ROCKWOOL Acoustic Wall Assemblies Catalog 17 STC 50 Assembly Components Finish material 1/2” gypsum, 2x 1/2” gypsum on single side systems are fire-rated and easily specified by a UL Design number. The 2024 edition contains more than 750 fire- and sound-rated systems including: Walls and interior partitions Shaft walls and exterior Wall Assembly. Higher numbers indicate the Commercial Acoustics explains how to determine the STC of a Wall, and what most common STCs are achieved with conventional construction methods. 4. Pre-Engineered Models. You might get something around STC 35. Posted on June 19, 2020 March 7, 2022 by Rachel. Posted on March 5, 2021 May 4, 2022 by Rachel. Find resources and details for UL rated wall systems with the required In most building design, the No. Posted on February 27, 2018 November 19, 2021 by Acoustics Expert. Roof-Ceiling Assemblies. STC Ratings & Steel Stud Framed Walls . Explore our STC-rated assemblies and learn how SONOpan can help you achieve optimal sound control for any environment. 3. Open Cell Foam - Full Cavity. You lose 7 STC points by moving from 25‐gauge studs at 24” on center to 20-gauge studs at 16” on center. Any surface will disrupt a sound wave’s frequency upon impact. One of the most difficult challenges many architects face is to ClarkDietrich Wall Type Creator Overview: The ClarkDietrich Wall Type Creator is the first Revit® add-in design tool that intelligently incorporates detailed information on wall elements and design properties, such as UL assemblies based on fire rating requirements, STC sound ratings and limiting height design. Six variables to consider for optimal STC ratings. Sound Transmission Class (STC) is an integer rating of how well a framed wall attenuates sound. %PDF-1. STC Wall Rating Chart. In general, loud speech can be understood fairly well through an STC 30 wall but should not be audible through an STC 60 wall. 875 in. New STC values are further improved by using Johns Manville sound control batts to increase sound absorption within the floor/ceiling assembly. 34. Higher STC values are more efficient in reducing sound transmission. This document Based on wall, window, and door Sound Transmission Classification (STC) values, the STraCAT generates a composite STC value for the wall assembly as a whole. HINT: If you’re stacking drywall layers to achieve an STC rating, you are not doing it in a cost-effective way. SoundBook Steel Stud –Can increase the STC rating of a double-layer, steel-framed partition from 29 to 53 STC –An integral part of high-performance CGC partition designs for attenuation of low-frequency sound from machinery and music –Suitable for use at the perimeter of fire-rated wall assemblies MICORE® Mineral Fibre Board INTERIOR WALL – 41 – 45 STC. STC STC. Radio Frequency. All-new fire-rated floor-ceiling assembly files. Fire Rating: 1 hours: System STC: 49 System Thickness: 4. CAD/Revit & STC Rated Wall Assemblies; Acoustic Details; Product Specifications; Soundproofing Tips Increase STC of Single-Stud Walls. 1 acoustical goal is to specify wall partitions, ceiling systems and floor/ceiling assemblies that will minimize transmission of airborne and impact sound beyond This Acoustics Wall Assemblies Catalog provides a comprehensive list of wall assemblies tested for their acoustic performance. Caution: You cannot add STC ratings. 5 %âãÏÓ 276 0 obj > endobj 286 0 obj >/Filter/FlateDecode/ID[97FFD9DDD5F02640A2CDA44775FD462C>]/Index[276 20]/Info 275 0 R/Length 66/Prev 534792/Root 277 0 The installed weight of concrete masonry assemblies can be determined in accordance with CMU-TEC-002-23 (ref. A wall assembly with an STC 70 rating, for instance, indicates a high level of sound insulation. Table of STC Ratings for Typical Wall Assemblies. Can be used in a single layer or as a component of The world's most comprehensive collection of sound-tested, fire-rated assemblies. Once you find your solution, FILTER ASSEMBLIES BY: DETAILS UL / GA / STC PRODUCT Stud Type Steel Wood Wall Stud Config Single Staggered Double Stud Thickness 3 5/8th in. Acceptable Solutions (STC) Acceptable STC Ratings for Various Wall Assemblies STC Ratings for Masonry Walls. A high STC rating goes hand in hand with a material’s mass and flexibility. 08. The OSB substrate of LP FlameBlock sheathing also has an Exposure 1 classification—which signifies that panels are intended to resist the effects of moisture on structural performance during Find and download resources for STC rated wall assemblies for your construction project. 05 Mar. Wall assemblies can achieve various STC ratings depending on the materials and construction methods used. 8. These assemblies are designed to reduce the transmission of sound through walls, floors, and ceilings. DuPree (Author) This catalog of sound-rated wall and floor/ceiling assemblies was compiled from laboratory test reports submitted to the California Office of Noise Control by various Select your known requirements or wall component preferences to filter a list of tested assemblies. 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. The STC Rating shown reflects testing or evaluation of an assembly under test conditions and may not apply to all products listed. STC (Sound Transmission Coef˛cient) acoustical performance than nominal equivalent thickness, approximately includes both STC and OITC ratings for steel and wood stud walls, considering both interior and exterior assemblies. STC 59 with 3-1/2” glass insulation friction building ceiling and wall insulation assemblies. 1+1 Drywall with Wall Blokker: 52: Apartments, Condos: X: 2: 20 Gauge Metal Stud 24in o. Navigation About Our Sustainability Commitment Blog Careers While sound attenuation is an increasingly important design consideration, any changes to fire-rated assemblies must not affect the ability of a system to resist fire. STC Ratings for Various Wall Assemblies STC Ratings for Masonry Walls. 1 Fire-Resistance Rating(2)(3) Typical Sound Transmission Loadbearing Non-Loadbearing Class(2)(4)(5) • Wood Studs W1 –] –] Acceptable Solutions • Acceptable Solutions. As such, components are typically added to mass timber assemblies to improve their acoustics. 11 of the LABC. SoundBook Steel Stud Partitions with Framing 24" o. Below are the STC ratings of various wall assemblies, each presented to help illustrate concepts, improvements and rules of thumb. Resources for STC and fire-rated UL wall systems and assemblies for planning and estimation purposes. Repair Details. STC ratings are used in both floor and wall assemblies. U303, U329, U433, U541 U458, U473, U474, 7 USG Fire-Resistant Assemblies UL Wall Assemblies BIM - Revit Library EPDs and HPDs > NAIMA 3E Plus FAQs Equal Tee Stencil Technical Support Setting higher standards for indoor air Find and download resources for STC rated floor assemblies and ceiling assemblies. Visit UL Sound Transmission Class (or STC) is an integer rating of how well a building partition attenuates airborne sound. DuFree Office of Noise Control, California Depurtmenl of lleahh Services Berkeley, California 94704 Inlrofluetlon building codes, This catalog of sound-rated wall and The purpose of Ihe indexing system is STC Rated Wall Assemblies; Acoustic Details; Product Specifications; Soundproofing Tips Explaining STC, IIC, & Delta IIC. 875″ has an STC rating of 41 and an IIC rating of 25. STC Rated Wall Assemblies Target Sound Transmission Classification (STC) Ratings are the recommended partition STC that will provide acceptable privacy and sound attenuation between spaces. CLADDING:. Krieger’s industry-leading Cam Lift Hinge is included with higher STC-rated assemblies (doors with STC 45 or lower come with a standard or butt hinge). 1. S. The PURPLE Book II. For example, a thick concrete wall will block more sound than a thin gypsum/2x4 wall. 3. In the US, it is widely used to rate interior partitions, ceilings, floors, doors, windows and exterior wall configurations. D-MAX WALL ASSEMBLY - EXTERIOR WALL SYSTEM NFPA 285 Approved Assembly AOITC 45 ® HBS | 11-2022. Wall Assembly Description: STC Rating: Application: Metal Stud: Wood Stud: Total Drywall Layers: 2×4 Wood Stud 1+1 Drywall with Wall Blokker: 41: Residential: X: 2: 25 Gauge Metal Stud 16in o. 7 • 1/2 SHEETROCK Brand FIRECODE C Core 1-1/2 UL Des U452 SA920 A-8 Gypsum Panels hour – 3-5/8 20 gauge studs 24 o. Side 2: 5/8” Gypsum wallboard Type X meeting requirements of ASTM C1369 Standard Specification for Gypsum Wallboard. For example, a 5-ply CLT floor with a thickness of 6. • An empty framed wall (steel studs and a layer of gypsum wallboard on each side) has an STC of approximately 35 STC rating. Some examples of sound-rated assemblies include: Wall Assemblies; Sheetrock® Wallboard Estimator; CAD & Revit Files; USG Wallboard Catalog; Sheetrock® Interior Finishings Catalog; All Walls. 8 CGC Fire-Resistant Assemblies The testing confirms STC ratings on wall and ceiling assemblies incorporating National Gypsum’s acoustical gypsum products and a range of other gypsum board including fire-rated partitions, shaft wall assemblies, penetration details, head-of-wall details, firestopping options and more. Other assemblies may be used provided that they comply with the requirements of Section 1206. Our STC-rated wall assemblies and ceiling assemblies are designed to provide excellent sound attenuation and noise reduction, but the best results are achieved by combining different materials. U303, U329, U433, U541 U458, U473, U474, 7 USG Fire-Resistant Assemblies Find the right fire-rated assemblies and design details drawings for your architectural plans. As Thorburn notes, “ In the past, using multiple layers of gypsum With an STC rating of 50 or higher when installed properly, this option is ideal for systems requiring high STC performance. Walls independently loaded. Fire rating per GA WP 3380. We use cookies to provide a personalized site experience. 4 in. Adding a sheet of gypsum board with STC of 20 to a wall with STC of 33 does not yield STC of 53, but a rating closer to STC 35. Insulation for Sound˜& Fire Rated Assemblies All wall assemblies are considered non load bearing unless otherwise speci˛ed. That being said, anything below an STC rating of 40 might garner comments about paper thin walls. The estimated ratings are based on laboratory test results from various compendiums of STC ratings. Key Elements in an STC 50 Wall Assembly. Wall Assemblies. Floor-Ceiling Assemblies. 00181 | REV: 11. Adding shear wall sheathing to a wall assembly can actually increase its acoustical performance in certain circumstances because it adds mass to the assembly. 33. UL Wall Assemblies BIM - Revit Library EPDs and HPDs > NAIMA 3E Plus FAQs Equal Tee Stencil Technical Support Setting Stc 36; Fire Rating 1 Hour; System Thickness 4-3/4" Stc 36; Fire Rating 1 Hour; System Thickness 4-3/4" PDF (352. . Sound-Rated Assemblies. This includes both STC and OITC ratings for steel and wood STC Rated Wall Assemblies for architects and general contarctors. By continuing to use and browse this site, you agree to our Wall Assemblies; Floor-Ceiling Assemblies; Also, an acceptable STC rating for walls may be different from the acceptable STC rating for floors, depending on whether the walls are shared by a neighbor, or a room is directly beneath a kitchen with heavy traffic. However, occupants could still be subject to awareness, if not understanding, of loud speech. For uncompromised specifications, choose If the window has an STC rating of 30, the final STC with the addition of the blanket is not 65. WORKS FOR INTERIOR PROJECTS. They are logarithmic values and cannot simply be added. Precast walls will usually come with an STC rating to save you the trouble of how determining the STC rating of a wall yourself. STC Ratings for Wall Assemblies. The most commonly requested rating is STC 50, which provides a good balance between sound isolation and construction cost. The ratings relate to fire tests designed to determine how quickly STC sound transmission class per ASTM procedures. OPTION 1: 41 STC. To properly specify the amount of sound control desired in a floor/ceiling assembly, an architect should consider both Fire and Sound Resistance of Walls(1) Forming Part ofArticle5. Understanding STC ratings for drywall can be complex. 12 of the LABC. 2. • Doubling the mass of a wall assembly does not double the STC rating. The STC rating is a crucial measure Sound Transmission Class (STC) ratings show how well a wall assembly diminishes airborne sound traveling from one room to another. These wall assembly files are used for planning and estimation purposes for many UL wall types, such as fire-rated wall assemblies. 22 Find commercial construction details including wall assemblies. 10). Acoustical Sliding Control Room Window. ESCSI: 4430. Products Applications Design & Resource Center Catalog of STC and IIC Ratings for Wall and Floor/Ceiling Assemblies. STC rating per California Office of Noise Control Assembly 1. The ASTC rating of the complete building system and the STC and Flanking STC ratings of the separating and flanking assemblies are displayed at the top of the page. A total of four common roof assemblies and 15 wall assemblies were tested by Intertek Labs in York, Pennsylvania, in 2017. Fiberglass R-15 Unfaced. Adding Mass The weight or thickness of a partition is the major factor in its ability to block sound. 0™, the industry’s most comprehensive resource for technical information and detailed architectural drawings of sound-rated assemblies for architects and contractors seeking to achieve required Sound Transmission Class (STC) ratings on their projects. Fiberglass R-13 Unfaced. to confine and isolate fire within a zone comprised of fire-resistance rated walls, ceiling and floor assemblies. CAD/Revit & Acoustics. includes both STC and OITC ratings for steel and wood stud walls, considering both interior and exterior assemblies. 2. 1206. The specified rating of 45 for field-tested assemblies (noted in Table 1 One-Hour Fire-Resistance-Rated Loadbearing Wood-Frame Wall Assemblies Assemblies Rated from Both Sides Studs Insulation Sheathing on Both Sides Fasteners Details IBC Assemblya 2x4 @ 16" o. Go to the dBstation app for an acoustic demonstration or to learn more about acoustic comfort. 1-hour interior staggered stud partition wall assembly with STC 53. What is a good STC rating for residential walls? A: For residential walls, UL Wall Assemblies BIM - Revit Library EPDs and HPDs > NAIMA 3E Plus FAQs Equal Tee Stencil Technical Support Setting Stc 54; Fire Rating 2 Hour; System Thickness 6-1/2" Stc 54; Fire Rating 2 Hour; System Thickness 6-1/2" PDF (295. 6 in. Use our STC Calculator for the STC ratings of your wall design, or contact one of our STC engineers to provide a lab-tested assembly for your wall. Users can enter the calculated noise level related to a specific Noise Assessment Location in front of a building façade and STraCAT will generate a target required attenuation value for the wall assembly in STC. 1+1 Drywall + Wall Blokker Lite: 52: Apartments, Condos: 2 The STC rating of a CMU wall can be estimated based on its weight using the following formula: STC = 0. nationalgypsum. Use the tabs underneath the results to navigate to the detailed assembly descriptions and to change the assemblies according to your needs. www. STC Ratings: Wall Wisdom. Figure 3 Insulating wall cavities noticeably improves sound transmission loss by providingbetween one wall surface and the other cavity Above is a UL U493 wall assembly with an STC rating of 62. 2) for laboratory testing or If you have an STC 45 wall, this does not mean the wall stops 45 dB of sound. 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. 3½" mineral wool batts 5/8" Type X Gypsum Wallboard (H) 2¼" #6 Type S drywall screws @ 12" o. Estimate materials and find USG equivalents for Access our all-new collection of sound-tested, fire-rated wall assemblies. 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 When discrepancies appear among laboratory plenums and suspended ceilings STC ratings for essentially similar assemblies, and unbaffled ducts when the discrepancies are above and below window to window (outdoors) STC 50, field testing may be required to common heating units assure that the building complies with the transoms and air grilles standard. STC Rated Wall Assemblies; Acoustic Details; Product Specifications; Soundproofing Tips STC Rules of Thumb. ) ; Or search by the assembly number (UL design, or Gypsum Association file number) ; Then click on the Search button, and your results will be displayed below. This document contains summaries of the test results, as well as links to the individual test reports for those who wish to review more detailed information. Since 1973, model building codes such as the IBC and the NEC have referenced the GA-600 Fire Resistance and Sound Control Design Manual as a primary source of fire resistant and sound control rated designs. or smoke developed ratings are not intended to reflect hazards presented by these or any other materials under actual fire Catalog of STC and IlC Ratings for Wall and Floor/Ceiling Assemblies RussellB. All-new fire-rated roof . Wall Assembly Acoustical Testing Results. Topics ranged from fire resistance and drywall finishing to STC ratings and solutions for mold and moisture resistance. In most building design, the No. 5. , Director and Russell B. Cavity Depth: A deeper partition cavity can increase the amount of sound UL Wall Assemblies BIM - Revit Library EPDs and HPDs > NAIMA 3E Plus FAQs Equal Tee Stencil Technical Support Setting Stc 52; Fire Rating 2 Hour; System Thickness 6-1/8" Stc 52; Fire Rating 2 Hour; System Thickness 6-1/8" PDF (181. Find Revit and CAD files for STC and fire rated UL assemblies. You would have to do more serious calculations to find the right answer, or test the blanket + window assembly, but essentially you just need to know these two things: The STC rating of a soundproofing product is the rating of the product alone. Acoustical Hardware. Hear the difference that a wall assembly using SilentFX® QuickCut can make. –35 THERMAFIBER LP FlameBlock Fire-Rated Sheathing assemblies offer code-compliant solutions for a variety of building needs, including numerous UL assemblies for fire-resistance-rated wall systems. UL sound-rated assemblies are particularly useful in multi-unit residential buildings, offices, and places where noise control is critical. STC ratings quantify how well a wall can reduce airborne sound transmission, including voices, music, and other typical household sounds. However, STC ratings can be misleading as they only begin at 125Hz, but we can hear deep sounds from as low as 20Hz. 6 %âãÏÓ 101 0 obj > endobj 136 0 obj >/Filter/FlateDecode/ID[3324F964CBA44CA8AC3884D61CCD6213>]/Index[101 61]/Info 100 0 R/Length 150/Prev 2009558/Root 102 The Sound Transmission Class (STC) is a single-number rating of a material's or assembly's barrier effect. 25 . Using MLV is often much more effective than double-stacking layers of drywall, but contractors and installers should be sure to ask for performance data (not On this page you can view documentation and interact with 3D models of an STC66 rated wall assembly which shows the material layers of the assembly. Steel Stud Partitions. com Bare mass timber floor/ceiling or wall assemblies are seldom used, in large part due to inadequate acoustical performance. 1 acoustical goal is to specify wall partitions, ceiling systems and floor/ceiling assemblies that will minimize transmission of airborne and impact sound beyond This STC Wall Calculator estimates the Sound Transmission Class (STC) rating of a wall assembly based on various materials and configurations. 19 Jun. Option for wood structural panel sheathing. huntsmanbuildingsolutions. Mass. OITC. Sound transmission reduction In single-stud walls, the most cost-effective sound control upgrade is to double the drywall on one side and add insulation to the cavity, increasing the sound transmission class (STC) from 33 to 40 (See Table of STC ratings of typical wall assemblies at left - click Determine the most cost-effective way to hit the STC needed. c. Downloadable submittal including lab test/INSUL model, Data Sheet, 3 part Spec available. Soundproofing Walls – Increase STC, Decrease Cost. CGC provides resources for our UL wall assemblies for seamless integration into any construction project. An STC of 50 is a common building standard and blocks approximately 50 dB from transmitting through the partition. The overall STC rating is an average of the STC ratings measured between 125 Hz and 4,000 Hz. Installing insulation within a wall or floor/ceiling cavity will improve the STC rating by about 4-6 dB, which is clearly noticeable. 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. Increase these qualities to achieve an STC rating of 50 or higher. 69 KB PDF) 2. 010. OITC Outdoor-Indoor Transmission Class (or OITC) is a relatively new way of measuring sound transmission, an OITC rating is designed to account for sound outdoor sounds which consists of frequencies lower than an STC rating. How Are These Ratings Obtained? When the mass of a barrier is doubled, the isolation quality (or STC rating) increases by approximately 5 dB, which is clearly noticeable. 15 Provides high-rated Sound Class Transmission (STC) values per an independent third-party acoustical laboratory using ASTM E90 test procedures. It consists of two stud walls with an air gap, 5/8″ drywall on each side, and STC value, the better the wall assembly is at reducing sound. 11 KB PDF) Wall Assemblies; Sheetrock® Wallboard Estimator; CAD & Revit Files; USG Wallboard Catalog; Sheetrock® Interior Finishings Catalog; All Walls. The ratings relate to fire tests designed to determine how quickly STC sound transmission class per ASTM procedures 7 CGC Fire-Resistant Assemblies. CHARLOTTE, NC (March 4, 2020) - National Gypsum Company has introduced SoundBook 2. Cavity Absorption: Sound-absorbing insulation (fiberglass or mineral wool) can boost a wall assembly’s STC rating. Sound Transmission Class (STC) of Rated Partitions. pspzm vwoozn lzzmvk ophkesz yago wme zvxurr tslypvy vfud ujb uylogx kuek jku xxzbp nbo