UL V497 PDF: A Comprehensive Overview (as of 10/02/2026)
UL V497 details exterior gypsum panel sheathing applications, specifying steel stud gauges, insulation types, and accessibility considerations, readily available as a specification PDF.
UL V497 represents a crucial specification within the construction industry, specifically addressing the safe application of exterior gypsum panel products used as sheathing. This document, accessible as a detailed PDF, outlines stringent requirements for achieving fire resistance and structural integrity in wall assemblies; It’s a cornerstone for builders, architects, and safety inspectors ensuring compliance with building codes.
The UL designation V497 isn’t merely a product standard; it’s a system-level evaluation. It considers the interplay between gypsum panels, steel studs (with minimum 25 gauge requirements), and glass fiber insulation (typically 3-1/2 inches thick). Understanding UL V497 is vital for projects demanding a one-hour fire rating for head of wall constructions, as indicated by UL Designs HW-D-0103 and HW-D-0076. Accessing the complete UL V497 PDF on the UL website provides comprehensive guidance for proper installation and usage.
What is UL and its Role in Safety Standards?
UL, or Underwriters Laboratories Inc., is a globally recognized independent, non-profit organization dedicated to public safety. For over a century, UL has played a pivotal role in developing and upholding rigorous safety standards for a vast array of products, including those detailed in the UL V497 PDF. UL doesn’t mandate compliance, but its standards are widely adopted by regulatory bodies and manufacturers.
UL’s process involves comprehensive testing and evaluation, culminating in certifications like Listed, Classified, and Recognized. These marks signify a product has met specific safety criteria. Regarding construction materials, like those covered by UL V497, UL assesses fire resistance, structural performance, and potential hazards. The UL 796 standard for printed circuit boards and UL 94 flammability testing are examples of their work. Accessing the UL V497 PDF demonstrates UL’s commitment to transparent safety information.
The Significance of the UL V497 Specification
The UL V497 specification is critically important for ensuring fire safety in wall assemblies utilizing exterior gypsum panel sheathing. This UL design, referenced in the UL V497 PDF, provides a tested and verified system for achieving a 1-hour fire resistance rating at the head of wall (UL DESIGN: V497). It details specific requirements for steel stud gauge (minimum 25 gauge), stud spacing (16 o.c. or 24 o.c.), and glass fiber insulation thickness (3-1/2 inches).
Compliance with UL V497 offers assurance to Authorities Having Jurisdiction (AHJ) and building owners. The UL designations HW-D-0103 and HW-D-0076 are directly linked to this specification. Furthermore, related UL design WHI-495-PSV-1325 demonstrates the interconnectedness of UL testing. Consulting the UL V497 PDF is vital for proper installation and use.
Understanding the Core Components of UL V497
The UL V497 PDF outlines gypsum panel, steel stud, and glass fiber insulation requirements, alongside accessibility details, forming the assembly’s core components.
Gypsum Panel Products Covered by V497
The UL V497 PDF specification primarily addresses the application of exterior gypsum panel products utilized as sheathing in wall assemblies. These panels must meet specific performance criteria outlined within the standard to ensure fire resistance and structural integrity. The document details acceptable gypsum panel types, including those with water-resistant cores suitable for exterior exposure.
It’s crucial to consult the latest version of the UL V497 document, as panel formulations and approved manufacturers can change. The standard doesn’t explicitly endorse specific brands but rather defines the necessary properties the panels must possess. Proper installation, as detailed in the specification, is paramount for achieving the intended fire-resistance ratings. The UL design, HW-D-0103 and HW-D-0076, are directly related to these gypsum panel applications.
Furthermore, the PDF emphasizes adherence to manufacturer’s instructions regarding panel cutting, fastening, and joint treatment to maintain the assembly’s overall performance characteristics.
Steel Stud Requirements (Gauge and Size)
According to the UL V497 PDF, steel studs forming the structural framework of wall assemblies are subject to stringent requirements. A minimum steel stud gauge of 25 gauge is mandated for compliance, ensuring adequate strength and stability. The specification details acceptable stud sizes, commonly 3-5/8 inches, though variations may be permitted depending on the specific design and load considerations.
Stud spacing is also critical; UL V497 addresses both 16 o.c. (on center) and 24 o.c. configurations, with fire-resistance ratings potentially differing between the two. The PDF emphasizes the importance of using studs that meet the specified yield strength and coating requirements to prevent corrosion.
Proper fastening of the gypsum panels to the steel studs is crucial, and the UL standard outlines approved fastener types and spacing. Adhering to these guidelines, as detailed in the specification, is essential for achieving the desired fire performance.
Insulation Type Specifications (Glass Fiber)
The UL V497 PDF explicitly details insulation requirements, primarily focusing on glass fiber insulation within specified wall assemblies. A minimum thickness of 3-1/2 inches is generally required for achieving the designated fire-resistance ratings. The specification outlines acceptable densities and thermal conductivity values for the glass fiber insulation, ensuring optimal performance.
It’s crucial that the glass fiber insulation is properly installed, filling the stud cavities completely without compression, to maintain its fire-resistive properties. The UL standard addresses the importance of facing materials, if any, and their compatibility with the overall system.
The PDF also clarifies that alternative insulation types may be permissible, but they must be tested and listed under UL to demonstrate equivalent performance. Strict adherence to these specification guidelines is vital for compliance.
Accessibility Considerations (One-Sided Access)
The UL V497 PDF addresses accessibility limitations, specifically detailing performance expectations for assemblies with one-sided access during installation. This is a critical factor in many construction scenarios where access to the wall cavity is restricted after the gypsum panel is installed.
The specification emphasizes that the fire-resistance ratings achieved under one-sided access conditions may differ from those obtained with full two-sided access. Therefore, careful consideration must be given to the installation method and the specific UL design being followed.
The PDF outlines specific requirements for fastener spacing and joint compound application to ensure adequate performance when one-sided access is the only option. Proper adherence to these guidelines, as detailed in the UL documentation, is essential for maintaining fire safety.
Detailed Technical Specifications within UL V497
The UL V497 PDF meticulously outlines stud spacing, steel gauge, insulation thickness, and joint compound application—critical details for compliant construction.
Stud Spacing (16 o.c. and 24 o.c.)
UL V497 explicitly addresses stud spacing as a crucial element in achieving specified fire-resistance ratings. The PDF document details acceptable configurations, primarily focusing on both 16 inches on center (o.c.) and 24 inches o.c. arrangements. These spacings directly influence the structural integrity and fire performance of wall assemblies utilizing exterior gypsum panel sheathing.
The specification clarifies that the chosen stud spacing must align with the tested and listed assembly details. Deviations from these prescribed spacings can invalidate the fire rating and compromise the overall safety of the construction. The UL design, V497, provides specific guidance on which insulation thicknesses and steel gauges are permissible with each stud spacing. Careful adherence to these guidelines, as outlined in the UL V497 PDF, is paramount for ensuring code compliance and building safety.
Furthermore, the document emphasizes the importance of consistent spacing throughout the entire assembly to maintain uniform performance characteristics.
Minimum Steel Stud Gauge (25 Gauge)
The UL V497 PDF unequivocally establishes 25 gauge as the minimum acceptable steel stud gauge for assemblies covered under this specification. This requirement is fundamental to achieving the documented fire-resistance ratings and structural performance. Utilizing a thinner gauge steel stud compromises the wall’s ability to withstand fire exposure and maintain its load-bearing capacity.
The UL standard dictates that all steel studs employed in UL V497-compliant constructions must meet or exceed this 25-gauge threshold. The specification details how this gauge relates to stud size (3-5/8 inches) and interacts with other components like insulation and joint compound. Deviating from this minimum gauge necessitates re-evaluation and re-testing of the entire assembly to ensure continued compliance.
The PDF serves as a critical reference for builders and inspectors, ensuring consistent material selection and adherence to safety standards. Proper gauge verification is essential for a successful UL certification.
Glass Fiber Insulation Thickness (3-1/2 inches)
According to the UL V497 PDF, a glass fiber insulation thickness of 3-1/2 inches is a non-negotiable component of compliant wall assemblies. This precise dimension is critical for achieving the specified fire-resistance ratings, particularly the 1-hour rating for head of wall constructions (UL DESIGN: V497). Deviations from this thickness invalidate the UL listing and compromise the wall’s protective capabilities.
The specification emphasizes that the insulation must be consistently maintained at 3-1/2 inches throughout the entire wall cavity. Compressing or reducing the insulation’s thickness diminishes its thermal performance and fire-blocking effectiveness. The PDF details how this insulation interacts with the 25-gauge steel studs and joint compound application.
Builders and inspectors rely on the UL V497 document to verify proper insulation installation, ensuring adherence to safety regulations and maintaining the integrity of the fire-rated assembly.
Joint Compound Application (Notched Trowel, 1/4 x 1/4)
The UL V497 PDF mandates a specific joint compound application technique for compliant assemblies: utilizing a notched trowel with a 1/4 x 1/4 inch notch. This precise method ensures consistent material distribution and proper bonding between the gypsum panels and steel studs, crucial for maintaining fire resistance. The specification details that setting-type joint compound is required, not just any standard variety.
This application method isn’t merely about aesthetics; it directly impacts the wall’s ability to withstand fire. The UL testing relies on this specific application to achieve the 1-hour fire rating (UL DESIGN: V497). Improper application, such as using a different notch size or insufficient compound, voids the UL listing.
Inspectors will verify this trowel notch size during construction, referencing the UL V497 document as the definitive guide. Consistent application is paramount for safety and code compliance.
UL V497 and Fire Resistance Ratings
The UL V497 PDF outlines a 1-hour fire rating for head of wall assemblies (UL DESIGN: V497), with designations like HW-D-0103 and HW-D-0076.
Head of Wall Fire Rating (1 Hour, UL DESIGN: V497)
The UL V497 PDF specifically details a 1-hour fire-resistance rating achieved through a defined assembly, designated as UL DESIGN: V497. This rating is crucial for ensuring building safety and compliance with fire codes. The assembly typically involves specific configurations of exterior gypsum panel sheathing, steel studs – often a minimum of 25 gauge – and glass fiber insulation, usually 3-1/2 inches thick.
Achieving this 1-hour rating requires adherence to precise installation guidelines outlined within the UL document. Joint compound application, using a notched trowel with a ¼ x ¼ inch pattern, is also a critical component. This rating applies to the head of wall construction, meaning the area where the wall meets the floor or roof deck. Understanding these parameters, as detailed in the UL V497 specification, is essential for architects, contractors, and building inspectors.
UL Designations: HW-D-0103 and HW-D-0076
The UL V497 PDF references specific UL Designations, notably HW-D-0103 and HW-D-0076, which represent distinct fire-rated wall assemblies. These designations aren’t merely identifiers; they encapsulate detailed construction parameters validated through rigorous testing. Each designation outlines precise requirements for materials – gypsum panels, steel studs, and insulation – and their installation methods.
HW-D-0103 and HW-D-0076 are critical for demonstrating compliance with building codes and ensuring fire safety. The UL report associated with each designation provides comprehensive information, including tested fire-resistance durations and acceptable variations in construction. Consulting the UL V497 document alongside these specific design reports is vital for accurate implementation. These designations confirm that the assemblies meet established safety standards, offering peace of mind to building owners and occupants.
WHI-495-PSV-1325 – Related UL Design
The UL V497 PDF often references WHI-495-PSV-1325 as a related UL design, signifying a connection to broader fire-resistance assembly validations. While V497 focuses on exterior gypsum panel sheathing, WHI-495-PSV-1325 may cover complementary aspects of wall construction or specific system integrations. Understanding this relationship is crucial for comprehensive fire protection strategies.
This related design likely details a complete wall assembly, potentially incorporating elements beyond the scope of V497, such as interior finishes or specific framing configurations. Accessing the WHI-495-PSV-1325 report alongside the UL V497 document provides a holistic view of the tested system. It’s essential to verify compatibility and adherence to both designs when implementing a fire-rated wall assembly, ensuring full compliance and optimal safety performance.
UL Certification and Compliance
UL certification for V497 requires adherence to standards like UL 796 and UL 94, encompassing flammability testing and basic requirements for listed products.
Basic Requirements for UL Certification
Achieving UL certification, crucial for UL V497 compliance, necessitates a rigorous process ensuring product safety and performance. Manufacturers must demonstrate adherence to specific UL standards, primarily focusing on material properties and construction methods detailed within the V497 specification. This involves submitting samples for comprehensive testing, evaluating flammability, structural integrity, and overall system performance under simulated conditions.
Crucially, manufacturers need to confirm their products meet the technical requirements outlined in relevant standards like UL 796 for printed circuit boards, if applicable, and UL 94 for flammability. Documentation, including material specifications, manufacturing processes, and quality control procedures, is essential. The type of UL certification – Listed, Classified, or Recognized – depends on the product’s application and the extent of UL’s evaluation, impacting market access and consumer confidence.
UL 796 Standard for Printed Circuit Boards
While UL V497 primarily concerns wall assemblies, the UL 796 standard for printed circuit boards becomes relevant when evaluating components within systems utilizing those assemblies. This standard assesses the safety of printed wiring boards, focusing on flammability, dimensional stability, and electrical insulation properties. It’s crucial for ensuring that any electrical components integrated into a V497-compliant wall won’t compromise the overall fire resistance or safety.
UL 796 testing evaluates materials used in PCB construction, including laminates, solder masks, and surface coatings. Compliance demonstrates a reduced risk of fire hazards and electrical shock. Manufacturers seeking UL certification for their PCBs must submit samples for rigorous testing, proving adherence to the standard’s stringent requirements. This indirectly supports the safety profile of structures built using UL V497 guidelines.
UL 94 Flammability Testing
UL 94 testing is a critical component of ensuring material safety within the context of UL V497 compliant assemblies, evaluating a plastic material’s flammability characteristics. This testing assesses how materials ignite, burn, and extinguish, assigning a flammability rating based on performance. These ratings – V-0, V-1, and V-2 – indicate the material’s resistance to vertical burning, with V-0 representing the highest level of flame retardancy.
Materials used in UL V497 wall construction, including joint compounds and potentially components within electrical systems passing through the wall, often undergo UL 94 testing. Achieving a favorable rating is essential for meeting fire safety standards and obtaining UL Listing. This testing helps mitigate fire spread and provides crucial data for assessing the overall fire resistance of the wall assembly, directly supporting the V497 specification.
Types of UL Certification (Listed, Classified, Recognized)
UL offers distinct certification types, each signifying a different level of evaluation relevant to UL V497 applications. “UL Listed” signifies comprehensive product testing, evaluating the entire product for safety hazards, and is often applied to complete wall assemblies meeting V497 standards. “UL Classified” verifies properties of a product based on specific standards, potentially focusing on a component within a V497 wall, like a fire-rated sealant.
“UL Recognized” applies to components within a larger product, not for standalone use. While not directly visible to end-users, these components contribute to the overall safety of a UL Listed assembly. Understanding these distinctions is crucial when interpreting UL markings on materials used in UL V497 construction, ensuring compliance and safety.
Applications and Use Cases for UL V497
UL V497 governs exterior sheathing, partition walls, and requires consultation with Authorities Having Jurisdiction (AHJ) for proper installation and product use.
Exterior Gypsum Panel Sheathing
UL V497 provides a standard specification for the application of exterior gypsum panel products utilized as sheathing in wall assemblies. This encompasses detailed requirements for achieving specific fire-resistance ratings, notably a one-hour rating for the head of wall construction – designated as UL DESIGN: V497.
The specification outlines crucial components, including the mandatory use of minimum 25-gauge steel studs spaced at either 16 inches or 24 inches on center (o.c.). Furthermore, it dictates the inclusion of 3-1/2 inch thick glass fiber insulation and the application of setting-type joint compound using a 1/4 x 1/4 notched trowel for optimal bonding.
Compliance with UL V497 ensures that exterior gypsum panel sheathing systems meet stringent safety standards, contributing to the overall fire protection and structural integrity of buildings. Always consult the complete UL V497 document on the UL website for comprehensive details.
Partition Wall Construction
UL V497’s relevance extends to partition wall construction, detailing acceptable configurations for interior, non-load-bearing walls. The specification focuses on achieving fire-resistance ratings, with UL DESIGN: HW-D-0103 and HW-D-0076 being key designations for specific partition wall assemblies.
Similar to exterior sheathing, UL V497 mandates minimum 25-gauge steel studs, spaced at 16 or 24 inches o.c., coupled with 3-1/2 inch glass fiber insulation. Proper joint compound application – utilizing a 1/4 x 1/4 notched trowel – is also critical for performance.
It’s crucial to remember that Authorities Having Jurisdiction (AHJ) must be consulted to ensure installations align with local building codes and specific project requirements. Referencing the complete UL V497 PDF on the UL website is essential for detailed guidance and compliance.
Authorities Having Jurisdiction (AHJ) Consultation
UL V497 provides a framework, but successful implementation necessitates consultation with Authorities Having Jurisdiction (AHJ). Local building codes often supersede or supplement the UL specification, demanding a thorough understanding of regional requirements. The UL document itself emphasizes this need, stating AHJs should be consulted “in all cases.”
This consultation ensures compliance with specific project needs, particularly regarding fire safety and structural integrity. AHJs can clarify acceptable materials, installation techniques, and required inspections. They’ll verify that the chosen UL-listed or classified products meet local standards.
Accessing the complete UL V497 PDF is a starting point, but it doesn’t replace the expertise of local authorities. Proactive engagement with AHJs streamlines the approval process and guarantees a safe, code-compliant construction project.
Resources and Further Information
Access the complete UL V497 specification PDF directly on the UL website for detailed guidance, updates, and to understand listed versus classified products.
Accessing the UL V497 Specification on the UL Website
Obtaining the official UL V497 specification PDF is readily achievable through the UL (Underwriters Laboratories) website. Navigating to UL’s online resources provides direct access to the most current version of this crucial document, ensuring users have the latest information regarding exterior gypsum panel sheathing applications.
The UL website offers a searchable database where you can locate V497 by its designation or keywords related to fire-rated wall assemblies. Downloading the PDF allows for offline access and detailed review of the technical requirements, including steel stud gauge specifications, insulation type guidelines (specifically glass fiber), and accessibility considerations.
Furthermore, the UL website often includes supplementary information, such as related UL Designs (HW-D-0103, HW-D-0076, WHI-495-PSV-1325) and links to relevant standards like UL 796 and UL 94, enhancing a comprehensive understanding of compliance and safety protocols; Regular checks are recommended to stay informed about recent updates and revisions to the specification.
Understanding UL Listed vs. UL Classified Products
When referencing the UL V497 specification, understanding the distinction between UL Listed and UL Classified products is vital. UL Listing signifies a product has been tested to nationally recognized safety standards, representing acceptance of the product’s properties. This applies to complete products, like assembled wall systems meeting V497 requirements.
UL Classification, however, indicates limited testing, often focusing on specific properties like fire resistance or component performance. A component used within a V497 assembly might be UL Classified, but the entire system needs Listing for full compliance.
Authorities Having Jurisdiction (AHJ) generally require UL Listed assemblies for building code adherence. Therefore, verifying that the complete wall assembly, not just individual components, carries a UL Listing related to V497 is crucial for project approval and ensuring public safety. Knowing this difference aids in proper product selection and application.
The Role of UL in Public Safety
UL, the Underwriters Laboratories, plays a critical role in safeguarding public safety through rigorous testing and certification, directly impacting the application of standards like UL V497. As a non-profit, independent organization, UL develops and publishes safety standards for a vast range of products, including those used in building construction, like gypsum panel systems.
The UL V497 specification, when adhered to, contributes to fire resistance and structural integrity, minimizing risks to occupants. UL’s independent verification provides confidence to consumers, builders, and AHJs that products meet established safety benchmarks.
By offering UL Listing and Classification services, UL helps prevent property damage, injuries, and potential loss of life. Their commitment to scientific and objective testing ensures that products perform as expected under various conditions, bolstering overall public well-being and building code compliance.
Recent Updates and Revisions to UL V497 (as of 10/02/2026)
As of October 2nd, 2026, the UL V497 specification remains a crucial document for exterior gypsum panel sheathing systems. While no major overhauls have been implemented recently, ongoing clarifications regarding joint compound application – specifically the 1/4 x 1/4 notched trowel requirement – have been issued to ensure consistent interpretation.
Minor revisions address updated material standards for glass fiber insulation, aligning with current manufacturing practices. Accessing the latest UL V497 PDF on the UL website is vital, as updates are frequently published to reflect evolving industry best practices and safety considerations.
Users are advised to regularly check for addenda and errata to the specification, ensuring compliance with the most current version. Staying informed about these changes is paramount for maintaining safety and code adherence in construction projects.