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Item: 221656

Securock® Brand UltraLight Glass-Mat Sheathing Firecode® X

High-performing, lightweight 15.9 mm (5/8") sheathing that’s designed to give your productivity a boost


Securock® Brand UltraLight Glass-Mat Sheathing Firecode X (UL Type USGX) is a lightweight, noncombustible, moisture- and mould-resistant panel available in 15.9 mm (5/8") that is designed for use under exterior cladding where conventional gypsum sheathing products have traditionally been used. Formulated to achieve all the strength and performance characteristics as standard Securock® Glass-Mat Sheathing at a significantly reduced weight, these panels are warranted for up to 12 months after application. These panels are coated with a glass-mat face and back to provide exceptional water resistance and maximize coverage of air/water barrier systems. This product can be used in any UL Type Design where Type USGX is specified.

Main Features

  • The lightest 15.9 mm (5/8")Type X glass-mat sheathing available—up to 15% lighter than other glass-mat sheathings
  • Improved coated fiberglass facer mat to maximize coverage of air/water barrier systems
  • Treated gypsum core, combined with fiberglass face and back, offers exceptional water resistance
  • Score and snap easily for quick installation
  • For use in most exterior systems when properly detailed by the exterior finish manufacturer
  • Meet or exceed the requirements of ASTM C1177
  • UL Type Designation USGX


  • Administrative Offices
  • Auditoriums and Gymnasiums
  • Bars Restaurants and Dining Areas
  • Department Stores and Boutiques
  • Dormitories
  • Exterior Soffits and Indoor Parking Garage
  • Guest Rooms and Suites
  • Health and Fitness
  • Traditional Offices


Submittal Sheet PDF 243.7 KB


  • Mould & Mildew Resistance No
  • ASTM E84
    • Flame Spread 5
  • ASTM Type ASTM C1177; ASTM D3273-10; ASTM E84
    • Flame Spread 5

Physical Data

  • Thickness (in.) 5/8
  • Color White
  • Edge Square Edge
  • Panel Size 4 ft. x 8-12 ft.


Documents & Files

Data/Submittal Sheets & Specifications

Data/Submittal Sheet (English) PDF 243.7 KB

White Papers

Sell Sheet (English) PDF 585.4 KB

Installation & Technical Manuals

Installation Guide (English) PDF 635.1 KB

SDS, Certifications & Reports

SDS (French) PDF 118.3 KB
SDS (English) PDF 88.2 KB
evaluation-reports (English) PDF 213.2 KB
evaluation-reports (French) PDF 213.2 KB


Warranties (English) PDF 161.0 KB


Product Attribute Report (English) PDF 885.1 KB

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