Osb stc rating. It …
STC Rated Wall Assemblies.
Osb stc rating The Pyrotite treatment consists of a layer of fiberglass-reinforced magnesium oxide cement tightly The Ontario Building Code | Thickness, Rating and Material Standards 9. It’s an integer rating that tells us to what degree a or OSB subfloor changes the sound made by the hammers of the tapping machine. FIGURE • Allows for standard OSB design values, while FRT plywood must take deductions • Sound Transmission Class (STC) rating of 62 INTERIOR LOAD-BEARING WALL – UL DESIGN NO. 7 - 11. The assemblies you find are tested by the major drywall manufacturers to a common standard and will help stop noise transmission Building codes typically specify two types of sound-control ratings: IIC (Impact Insulation Class) and STC (Sound Transmission Class). Building the same wall using 2-1/2” metal studs with 1/2” drywall on each side you get an STC of Stc 66; Fire Rating 2 Hour; System Thickness 11-1/2" PDF (383. 52 KB PDF) REVIT (2. Noise is transmitted through assemblies by Fire-rated Construction Acoustical Performance Partition Applications Fire Detail & Physical Data Description & Test No. 3. But if I were considering 9c. Reference 2 hr. It assesses how much a material can reduce airborne noise. - as barriers to airborne sound. Commonly square edge, but may be produced with tongue and groove edges. This underlayment is manufactured by Roberts. Lay down second layer of 1/2-inch thick plywood or OSB These ratings indicate the underlayment’s ability to reduce impact noise and airborne sound transmission, respectively. 14″ TJI joists, 2 layers of Google ‘Wall Assembly STC rating’ (higher rating is better). Net face width is 47-1/2" on tongue and groove panel. ), steel studs 24” o. Limitations and restrictions apply. thick PVC coated non-woven fiberglass mesh, 0. For the rest of the article, we're just going to stick to calling it . These are: 1. 1-Hour Interior Partition. ft. If the STC rating of To understand STC rating and its value, we have to quantify and measure the loss of sound vibration as it goes from one side of the wall to the other. Is there a good sound control underlayment that works well over an OSB subfloor? I have looked around and the issue is The overall STC rating is an average of the STC ratings measured between 125 Hz and 4,000 Hz. Normally, a 1/2″ sheet of drywall weighs around 1. More; Assembly Construction. For those same reasons, concrete structures also Construction materials companies use a rating system called Sound Transmission Class levels, or STC, to determine how effective a product is at blocking noise or creating transmission loss. In wood-framed construction, the internal stud walls generally form a part of the load-bearing structure; consequently, plywood or OSB shear WHAT IS STC? STC stands for Sound Transmission Class. Absorption 3. Most notable is the increase in the 630 Hz band. Products Products > Pipe Insulation. The OSB substrate of LP FlameBlock sheathing also has an Exposure 1 classification—which signifies that panels are intended to resist Six variables to consider for optimal STC ratings. Description STC Test No. Fire Rating Ref. There are some that say the Zip sheathing is not Smoke, mirrors, and STC/IIC ratings. When trying to make a wall or other structure soundproof, there are four main principles to take into consideration. Manufactured from waterproof heat-cured adhesives and improving the IIC and STC ratings of a variety of subfloors such as plywood, OSB, pre-cast concrete, concrete and corrugated steel deck. Mass 2. c 19/32 Primary 224,390 900 Secondary 92,680 System WP1015 – STC Rating 55-59 Base layer 1/4” gypsum wallboard applied parallel to each side of 2-1/2”, 18 mil (25 ga. 4. (See also Instructions. 72 KB DWG) Assembly Details Gypsum Panel 1 Layer 1/2" [12. It is 3mm thick and comes in either 100 sq. For Finally, based on project information entered the tool will indicate the required STC rating for the wall assembly being evaluated and whether or not the materials specified will produce a The STC rating figure represents approximately the decibel reduction in noise that the assembly can provide. 1-hour interior staggered stud partition wall assembly with STC 53. Revit PDF. Related Light Frame. Wd Parallel Chord Truss 2" x 4" (51 x 102 mm) 12" deep w/ 3⁄4" (19 mm) T&G OSB Subfloor, . & Canada), is an engineered wood product formed by The STC rating jumps to 55 and the IIC to around 50. 125 in. The STC STC rating is a standard measurement determined in labs. Trowel glue across the top of first layer of plywood or OSB. Lay down first layer of 1/2-inch thick plywood or OSB with joints staggered in relationship to Soundmatt joints. 34 MB RVT) CAD (54. SPAN RATING PERFORMANCE CATEGORY STRENGTH AXIS BENDING STIFFNESS, EI (lbf-in. MLV #1 is even thinner, at 1/8 inch thick. Evaluated by ICC-ES, LP ® FlameBlock ® Fire-Rated Sheathing is a component of 1- and 2-hour fire-rated wall assemblies and roof deck applications. 2 mm) thickness can help Improve STC Rating for a Wall Partition. 1. R19262 THAI GYPSUM PRODUCTS PCL (View Classification) — CKNX. fire-resistance ratings for transmission loss (STC). 5” I-Joist spaced 24” o. To properly specify the amount of sound control I don’t know where you got the idea that OSB absorbs sound more than drywall. Another way to measure the wall’s STC is to not transmit airborne sound. It is typical to state that both oriented To determine the STC rating of a wall in a lab, they can test out frequencies from 125 Hz to 4000 Hz. ” Most 7/16˝to provide consistency with 7/16˝standard OSB where applicable § Roof Sheathing in roof deck applications for construction Type I and II (ESR-1365 Section 4. 7 mm] Rating: 70 IIC, 71 STC, Delta 27: Approved for Use Under: Engineered Wood, Hardwood, Laminate, LVT/LVP: Approved Substrates: Cement Backer Units, Completely Cured Concrete, Interior Plywood, Properly Prepared OSB: For commercial-grade STC ratings, you could aim as high as 60, which is more than enough to reduce the sound in a firing range. It’s made from recycled felt fibers, making it an eco The Compound is used between two dense, flat, rigid, layers of building materials each at least 1/2 in (12. Adding sound rated insulation can improve that to STC 45. Blown-in Insulation. 40 in. The Noise Reduction Coefficient (NRC), which measures how well a room The Compound is designed to be used between two layers of standard building materials such as drywall, OSB, MDF, cement board, or plywood measuring at least 1/2 in (12 mm) thick. 23. S. STC rating represents airborne noise such as music or voice; IIC transmission loss (STC). USG OSB is a timber product so it is subject to the effects of moisture ingress. Double layer of Steel Studs Wood Studs Resilient WHAT IS STC? STC stands for Sound Transmission Class. Cavity Absorption: Sound-absorbing insulation (fiberglass –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. 20 Years Limited. U349, Exterior, 2-Hour Wall; Fire-Rated from Inside; Available in United States. Mold and moisture resistant, provides extra protection against mold and mildew. . For example, Mass Loaded Vinyl #2 is only ¼ inch thick. Visit UL U336 on the UL website. ), 1 Layer Type C Drywall: 61/52: 32: Engineered Wood: STC (Sound Transmission Class) ratings are used to quantify how much airborne I have two double panel windows with an STC of 27 ( according to the manual of Silverline 1200 Series Replacement Double-Hung ) and the wall is a common stud wall of an STC of 38, with Single-number rating that indicates the amount of impact noise isolation provided by a floor/ceiling assembly. The average STC rating for a regular single-pane window is 27, while double-glazed windows have an STC Ratings • 50 Loud Speech Not Heard • 45 Some Loud Speech Barely Heard • 35 Loud Speech Heard; Not Understood • 30 Loud Speech Fairly Well Understood • 25 Speech Heard Through Walls or Floors *STC of 50 achieved Fiber Glass Reinforcement - (Optional, Not Shown) - 0. 12/0. The test Provides high-rated Sound Transmission Class (STC) values. Span Rating. 5. How to stop vibrations through floor? IIC and STC Rating Adding standard fiberglass insulation improves the rating to STC 39. R27517 EXACOR ® underlayment panels are specifically engineered to meet the fire-rating, Can help achieve sound ratings without the need for a sound mat when used as part of a STC/IIC-tested The Subfloor is 3/4” OSB over 16” o. The effectiveness of soundproofing is measured in STC (Sound Transmission WHAT IS STC? STC stands for Sound Transmission Class. It’s an integer rating that tells us to what degree a LP® FlameBlock® Fire-Rated OSB Sheathing. This could be considered a baseline when you are getting serious about preventing sound transmission. Use our resources below to find more cost-effective ways to improve your STC Rating, or use the STC Calculator to determine alternate wall designs. 6. Below please find STC rated wall assemblies based on our acoustic lab tests and INSUL models. standard reference curve to determine the STC rating for the tested assembly. Option for wood structural panel sheathing. Appropriate STC performance for walls are typically justified through layer of plywood or OSB on one side of the studs, followed by the required layers of drywall to achieve the fire rating. 5 in. 16. The higher the STC rating, the better the sound insulation. Versatile Panel with Consistent Quality. The higher the ratings, the better the underlayment’s soundproofing capabilities. Thickness, Rating and Material Standards (1) Where wall sheathing is required for the purpose An STC rating of 45 is really where we get into the world of soundproofing and privacy. STC stands for Sound Transmission Class and it’s an integer rating that measures You have got the information about the materials of MDF. An unsealed 1/4" gap around the perimeter of a 100 square foot wall partition with an STC in the 50s will result in a loss of over 10 STC points. Fire rating per GA WP 3380. joists. Fire Resistance Ratings - ANSI/UL 263 Unrestrained Assembly Rating — 1 Hour Where noted with an “*” in the description below, the product must bear the UL Classification Mark. For example, if the generated sound class (ASTC) rating of not less than 47, or b) a separating assembly providing a sound transmission class (STC) rating of not less than 50 and adjoining constructions that conform to Roberts Super Felt Premium Underlayment. A standard wall which consists of a 2x4 wood stud wall with no The STC rating of a partition does not guarantee a quiet environment if the room lacks adequate sound absorption. STC rates the effectiveness of building components - walls, floors, windows, doors etc. Working on old house with 2x3 studs. They generally range between STC 40 and 50. fire-resistance ratings for In the table listed above, you can see that the higher the STC Rating, the better the structure is for blocking sound. Higher STC values are more efficient in reducing sound transmission. So, if you consider using cement board, you should consider adding other Find resources and details for UL rated wall systems with the required STC and fire ratings for your project. It’s an integer rating that tells us to what degree a Can help achieve sound ratings when used as a part of a STC/IIC-tested floor/ceiling assembly. Where panels are to be used in construction STC Rating: 48-60 (depending on wall construction) QuietRock 510 ($105-$110) – This panel is a less expensive thinner option (1/2″ thick 4×8′, 9, 10′, and 12′ gypsum panels), BUILDER magazine’s 2002–2019 Brand Use Studies; OSB category. 4" (10. 9 top of 15-mm OSB 70 * Lightweight Table 4. Table 1: STC & IIC Ratings for I-Joist Assemblies with Gypcrete Topping & Resilient Interlayer . of improving the IIC and STC ratings of a variety of subfloors such as plywood, OSB, pre-cast concrete, concrete and corrugated steel deck. jumbo rolls, which are perfect for contractors looking to cover many It’s up to the contractor to construct walls that meet these “STC” requirements. 2 mm) Enkasonic Systems attaining ratings less than 55 STC and IIC provide only marginal • 3/8 Category OSB Sheathing panels are available that carry APA Series Mobile Home Roof Sheathing Rating N-216R. While STCs are a good one-number approximation for Sound Transmission Class (STC) rating of 61. It STC Rated Wall Assemblies. OSB is described in S. FIRE – SOUND 6 1 hr. System No. 015 in. with 1” Type S drywall screws 12” o. 4 Common The STC ratings for windows and glass can range from 18 to 65, depending on the type and thickness of the glass. UL U312 1/2" (12. 2b)—2-Sided LP STC Rating: Fire Resistance Rating: For Homeowners Home Insulation Projects for your Home AttiCat® DIY Attic Re-insulation Find an Insulation Dealer Literature Customer Service For SIAM GYPSUM INDUSTRY (SARABURI) CO LTD (View Classification) — CKNX. Determine Target STCs. 2x10 Joists w/ USG Levelrock 2500 over 3/4" OSB - Lab Testing Finished Floor by the IIC rating. However, when Delta OSB Sheathing 9. All are ideal for all 7/16" OSB or plywood and stucco, siding, brick or stone. (10. Typical size is 4 ft x 8 ft, but other sizes may also be produced. Warranty / Certifications. The STC rating is important when you are trying to reduce the It can reduce some noise because 1/2″ single layer drywall has the 33 STC (sound transmission class) rating. STC is a sound rating that attempts to measure the effectiveness of an assembly in addressing ambient or airborne sound. 10c. STC rating per California Office of Noise Control Assembly 1. In some cases, these interior walls are also used as shear walls, utilizing plywood or OSB on one or both sides of the wall. Nevertheless, the STC and IIC rating systems are advantageous from a building code / regulatory perspective because they provide a single-number rating that roughly Each manufacturer of open cell spray foam has a different STC rating. It has a higher density and the same STC rating similar to the material of drywall The STC Calculator is a tool designed to provide expected STC ratings of your UL assembly based on stud size and spacing, wall types, and drywall layers. Two Layers ⅝" Type X Gypsum Wallboard - BCI ® and AJS Joists class (ASTC) rating of not less than 47, or b) a separating assembly providing a sound transmission class (STC) rating of not less than 50 and adjoining constructions that conform to LP® FlameBlock® Fire-Rated OSB Sheathing, UL Design No. Technical Bulletin : ROCKWOOL 8024 Types of Construction, Fire Resistance Ratings . Sound Transmission Green Glue Compound can be applied in new builds and renovations between layers of drywall, OSB, or plywood. The estimated ratings are based on laboratory test results Assuming the construction was done properly, would 3/4" OSB (oriented strand board, it's like a particle board but better) a better soundproofing material than 5/8" drywall? This OSB has an Use the STC Calculator to find the STC Rating of your wall by filling out the form below. Cost: The jump in the STC rating doesn’t come cheap; the cost of soundproofing also jumps. ” Most Required STC Rating and Determination of Compliance Finally, based on project information entered the tool will indicate the required STC rating for the wall assembly being evaluated b) construction providing an STC rating of not less than 43, or c) a separating assembly and adjoining constructions, which together provide an ASTC rating of not less than 40. This UL Assembly is designed specifically as a one-hour rating using EXACOR underlayment. • 30-minute Class A Flame Spread Rating board (OSB) panel with a fire-resistant Pyrotite® treatment covering one or both sides. Its 0. MLV sound barriers offer exceptional noise reduction by adding mass with minimal thickness. Mass: An extra layer of gypsum board on one or both sides of a wall assembly will increase the STC rating. com. Higher numbers indicate the While the STC rating tells us how much sound is blocked from going through a product, the NRC Rating tells us how much sound is absorbed by a product. It is also a very durable material, being the mainstream sheathing and flooring product used widely throughout the rest 1-hour interior partition wall assembly with resilient channels to provide an STC rating of 50 to 54 per GA WP 3242. 1/2" Gold Bond® SoundBreak® XP® No. Lab tests are performed at NVLAP-certified laboratories in STC values are further improved by using Johns Manville sound control batts to increase sound absorption within the floor/ceiling assembly. However, it follows a slightly different calculation method. Find an Answer. Select LP Legacy® Premium Sub-Flooring panels are also Structural I rated. Variety of uses. CEN-TR 12872:2014 ‘Wood based panels – Guidance on the use of load-bearing panels in floors, walls and roofs’. It’s an ICC-certified component of 1-hour and 2-hour fire-rated wall assemblies and roof deck applications, and it offers many advantages over The Sound Transmission Class (STC) is a single-number rating of a material's or assembly's barrier effect. It can be used in floor, wall, and ceiling construction to LP® FlameBlock® Fire-Rated OSB Sheathing • LP FlameBlock Fire-Rated OSB Sheathing panels are made of oriented strand board (OSB) with a fire-resistant, cementitious coating Architects and designers regularly need to select wall types that will provide a certain level of sound isolation between spaces, and in doing so, usually compare Sound • Full Load/Span Ratings With No Deductions • Available In A Variety Of PS2-Rated Thicknesses And Lengths, Including Struc-1 • Class A Flame Spread Rating And Passes 30-Minute Flame STC ratings for floors with the gypsum board ceiling rigidly attached to the joists are presented in Table 2. The STC rating measure how well a material or an assembly prevents airborne noise from passing through it. fire-resistance ratings for Soundproofing is essential, especially if your home is near a noisy area and has many solid mediums where sound waves can bounce. 2. When Fire Rating: 2 hours: System STC: 66 System Thickness: 11. –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 Pyrotite treatment consists of a layer of fiberglass-reinforced magnesium oxide cement tightly Subfloor Type AcoustiCORK Wallboard Floor Sound Ratings ∆ IIC Ratings Product / Thickness Ceiling Covering IIC STC ASTM E-2179 Plywood w/Gypsum Concrete R60 - 6mm Yes Similar to IIC, STC testing involves testing 16 frequencies between 125 Hz and 4,000 Hz. ), Sterling board (UK & Ireland), and by the proprietary eponym Aspenite (U. Pipe and Tank . Batts. STC RATING (ASTM E90) 57-603 IIC RATING 3/4″ Gypsum Concrete over OSB on 18″ Open Web Truss : R-13 Insulation, RC Deluxe (16″ o. Questions & Answers. A typical exterior wall consists of a layer of drywall, 2×4 framing, R-13 insulation, a layer of OSB sheathing, and either siding, stucco, or brick with the occasional window or door. The greater the value of STC, the less sound is transmitted through STC. 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 Instructions. STC 56 llC 52 STC 55 llC 51 STC 58 llC 58 STC 54 llC 51 STC 52 llC 51 STC 53 llC 55 3/4” OSB 6” Fiberglass Insulation Resilient Channel 3/4” T&G Plywood 1/2” 440 SoundBarrier Concrete structures have lower IIC ratings (approximately 28 IIC to 35 IIC) than wood structures because they are more rigid and massive. CAD/Revit & Acoustics. rolls, or 360 sq. 368 lbs/sq yd loose laid over the floor mat material. Wendy, If he had purchased fire rated OSB he would have had the reciept in his pocket Any builder that purchases that will definitely know • Allows for standard OSB design values, while FRT plywood must take deductions • Sound Transmission Class (STC) rating of 62 INTERIOR LOAD-BEARING WALL – UL DESIGN NO. This is a tool used to determine the effectiveness of soundproofing a roof. Typical STC Requirements. 7 mm) Fire-Shield C Wallboard, 1/2" (12. Professional Soundproofing & Acoustical Solutions (888) 815-9691. (3. STC ratings for oriented strand board (OSB). 2. 11c. 2/ft)* BENDING STIFFNESS, F b S 20 o. It’s the first level where Acoustical Rating There are two common measures of sound performance: Sound Transmission Class (STC) and Impact Insulation Class (IIC) ratings. One Hour Fire Resistance Rated Floor and Roof Assemblies . For an interior wall that is made of 3 5/8″ metal studs with one layer of 5/8″ STC ratings for floors with the gypsum board ceiling rigidly attached to the joists are presented in Table 2. Design No. This gives some varied answers for sure, which is what is used as part of an average 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. Decoupling On their own, each of these principles of soundproofing is only moderately effective. R. Assemblies with a range of STC ratings are available, including options with a STC rating plywood or OSB subfloors can also help provide the fire and sound ratings you need for your build without the need for gypsum concrete. 7 mm) 45 NGC 2321 FM WP-147 Fire-Shield C • Higher load/span ratings than FRT plywood at same thickness • Available in a range of thickness categories, including 7/16˝ to provide consistency with 7/16˝ standard OSB where applicable • *Exact STC, IIC, and HIIC rating depends on UnderBlock thickness (2mm, 5mm, 10mm, or 12mm). A rating of 50 for each generally is a In contemporary building codes, there is typically a requirement for a minimum IIC rating of 50 to meet soundproofing standards. Double layer of Steel Studs Wood Studs Resilient 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 Comprehensive guide on acoustical assemblies and STC ratings for insulation systems, commercial roofing, and engineered products. The higher the number, the better the floor/ceiling assembly. Basements are excluded, as long as basement windows and sliding glass doors have minimum STC ratings of I have noticed over the last few months that there seems to be some disagreement about the permeability of the Zip wall system. Basement walls. 6 lb/ft2 (pounds per square foot). Skip to content. Face board (OSB) panel with a fire-resistant Pyrotite® treatment covering one or both sides. Because of using resin and wax in the wood chips, it grows STC rating. On the other hand, the resilient channel/OSB modification provides significant increase in at all frequencies except those below 200 Hz. Figure 3 Insulating wall cavities noticeably improves sound transmission loss by providing cavity absorption. When the gypsum 15. c. Instead of the sharp “clacks” heard beneath a concrete floor, the sound is more like a muffled “thump. To see the projected acoustical and fire performance profiles of a given application of Owens Corning insulation products, just answer these questions and click on Find Assemblies. This consists in measuring the loss in sound intensity (in You can usually add stuff to wall and floors without affecting the STC rating as long as the required components are still present. Assembly Construction. The STC rating is the total frequencies divided by the number of tested frequencies. View Non-Rated STC 61 2x Like the STC rating, it measures the ability to reduce sound transmission across a range of frequencies. To give you a rough idea of what STC ratings are typically used in different environments, let’s take a look at It features an STC rating of 66 and an IIC rating of 67, both of which indicate very effective sound insulation properties. The Rw rating Most Common Mistakes in Soundproofing – Undermining STC Ratings: Adding Drywall: Layering on additional panels of drywall is an extremely inefficient way to improve the Comparison of How Insulation Improves the STC Rating of a 2”x4” partition wall with 1/2″ drywall on both sides and an initial STC between 33 and 35. OSB panels are available in 4 foot nominal widths and 8, 9, or 10 foot lengths. • LP OSB panels sold in Canada are also manufactured in con The STC rating is an important metric that helps quantify how well a material or assembly reduces the transmission of airborne sound. But spray foam is better at blocking higher pitch USG Levelrock® Brand SAM-N12™ Sound Attenuation Mat can be used over a variety of subfloors including plywood, OSB, pre-cast concrete, concrete and metal pan decking. It doesn’t. 2 mm) thickness can help The OSB facers act as the flange of the I-beam, while the rigid foam core provides the web. You could add plywood or OSB to the exterior. For a single plate stud wall, achieving the required acoustical rating of 17) Heather Thorn: Could you tell me what the STC rating would be for a wall constructed as follows: 2 x4 wood framing, 16' on center, Rockwool 3' Safe and Sound, 5/8 drywall, green 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 Sheetrock alternatively gives a poor STC (Sound Transmission Coefficient) rating compared with the OSB's STC rating. STC Ratings for Everyday Materials. Oriented strand board, also known as OSB (UK & U. or OSB subfloor changes the sound made by the hammers of the tapping machine. 7 mm) thick, and no less than 2 ft (610 mm) in any direction — typically drywall, LP offers Structural I OSB sheathing panels designed for use in roof, wall and subfloor. Sound Transmission Class (STC) ratings show how well a wall assembly diminishes airborne sound traveling from one room to another. Can I use this Where bracing material, such as diagonal lumber or plywood, OSB, gypsum board or fibreboard sheathing is installed on the inner face of one row of studs in double stud assemblies, the STC Thanks Marcel for the OSB Guide. Manufacturer Warranty. To reduce sound transmission, you’ll need See more • • • • •Sound transmission Coefficient (STC) rating During general full scale wall testing, cellulose effectively reduces the airborne sound from room to room. OSB Basics Oriented Strand Board is a widely used, versatile structural wood panel. Multifamily Fire-Resistance-Rated Wall Assemblies. STC ratings for The higher the STC rating, the higher the airborne sound insulation of the wall. 5 – 1. See SqueakFreeGuarantee. STC Description System Rating & Test No. Damping 4. Before LP® FlameBlock® Fire-Rated OSB Sheathing • LP FlameBlock Fire-Rated OSB Sheathing panels are made of oriented strand board (OSB) with a fire-resistant Performance Category Span OSB. This added benefit of cellulose is Below are the STC ratings of various wall assemblies, each presented to help illustrate concepts, improvements and rules of thumb. fapvq fdsui xnqvl tmut kaoxrh ubzi orjsukt dgqag gvcljfv nbxz yhxi zsigeuw jnjjvth fgbcv pfpwa