Improving fire protection for homeowners and their families

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1. Kitchen     2. Bedroom
Fire-Resistant Gypsum Panels help address a key homeowner concern – fire safety.
Physical Description
All gypsum panels are fire resistant and produced in a range of thicknesses, core formulations and optional special performance enhancements. The specialty products described on this site are examples of some of these options. For our discussion here we will focus on panels manufactured with a Type X core in a 5/8” (15.9 mm) thickness, widths of 48” (1.2 m) or 54” (1.4 m) and lengths from 8’ (2.4 m) to 16’ (4.9 m) or a Type C core in 1/2” (12.7 mm) or 5/8” (15.9 mm) thicknesses, widths of 48” (1.2 m) or 54” (1.4 m) and lengths from 8’ (2.4 m) to 16’ (4.9 m). In Type X products, the primary core additive is glass fibers. In Type C panels, the core is enhanced with glass fibers as well as other additives to provide an even higher level of fire-resistance than Type X panels. Facer materials for panels may be either enhanced, recycled paper or fiberglass mats. Individual boards are produced with square edges along the width of each panel and tapered edges along the length to simplify joint finishing. The applicable product standard for Fire-Resistant Gypsum Panels is ASTM C1396. Consult your gypsum manufacturer for other available product variations.

Advantages and Benefits
Enhanced fire resistance was one of the first specialty performance characteristics added to standard gypsum panels, but until recently it has been primarily used in commercial and multi-tenant applications. It has much to offer single-family residential design and construction too.

o Fire Resistance – Whether Fire-Resistant Gypsum Panels are produced with Type X or Type C core formulations, they are designed to be used in the construction of wall and floor/ceiling systems that reduce flame spread and smoke generation better than standard gypsum board. Fire-Resistant Gypsum Panels are classified for use in UL assemblies that can deliver fire ratings up to 3 hours in ceilings and as long as 4 hours in wall and column systems. To review a collection of these system assemblies that meet a wide range of design requirements, refer to GA-600 Fire Resistance and Sound Control Design Manual. Any Fire-Resistant Gypsum Panel classified as a Type C or Type X product is approved for use in any fire-rated assembly where the corresponding panel type is specified.

o Construction Efficiency – Fire-Resistant Gypsum Panels are just as easy to install and finish as the standard gypsum panels covering the largest proportion of interior wall and ceiling surfaces in most single-family homes. Score-and-snap cutting and reliable compatibility with a broad range of finishing treatments make them a popular and efficient construction choice to provide enhanced fire safety in new construction as well as remodeling.

o Noise Attenuation – Gypsum drywall panels have long been recognized as an effective material in the construction of interior partitions designed to help control unwanted noise because of their mass and density. Fire-Resistant Gypsum Panels perform this role especially well. To design interior walls and ceilings that meet improved acoustical performance objectives, refer to GA-600 Fire Resistance and Sound Control Design Manual for assemblies with higher tested sound transmission class (STC) values. Fire-Resistant Gypsum Board can be used in any assembly where the corresponding UL-classified 1/2” Type C or 5/8” Type X drywall is approved. more

o Other Specialty Performance Properties – Fire-Resistant Gypsum Panels are also manufactured with a number of added performance characteristics as well. Consult individual gypsum panel manufacturers for other features and combinations of features that may include:

  • Mold/Moisture Resistance
  • Abuse Resistance
  • Impact Resistance
  • Reduced Panel Weight
  • Enhanced Ceiling Span Characteristics

Limitations
To achieve the performance objectives specified for the walls and ceilings of a single-family residential project, a number of important limitations should be followed to ensure success. These recommendations are intended to provide general information only about considerations that are common in this category of special performance gypsum products:

o Fire-Resistant Gypsum Panels are intended for interior use only
o Fire-Resistant Gypsum Panels are nonstructural and are not designed to be a fastener base for mounting other materials to walls or ceilings
o avoid prolonged exposure to temperatures exceeding 125°
o wall and floor cavities must be dry before closing up or applying interior finishes
o not intended for constant exposure to moisture, ponding or cascading water
o to prevent mold and mildew growth, avoid exposure to water during handling, storage, installation and after installation is complete

Refer to GA-216 Application And Finishing Of Gypsum Panel Products for specific guidelines related to the application and finishing of gypsum panel products.

Products vary by brand. For more specific limitations related to the gypsum panel being considered, consult with the product’s manufacturer.

Frequently Asked Questions
Below are answers to typical questions our technical experts address on a routine basis. These answers may provide additional information you are seeking as well. To submit an inquiry of your own, click here.

1. Are 5/8” thick gypsum panels made without a fire-rated Type X core?

This question is often asked by individuals looking to repair to a 5/8” regular board already in place. The short answer is no. At one time, there were 5/8” boards made with a typical core, which is why you will see these in some existing buildings. Their thickness and weight helped enhance sound control of the wall. However, the industry moved away from these in the 1990’s in order to avoid confusion between regular 5/8” panels and Type X panels. Installation of the wrong panel type in areas where Type X was required was seen as a potential fire-safety issue.

If you are repairing a wall that has typical core 5/8” board, you can use the Type X on the market today and create a perfect repair.

For Further Information
To read more about the UL testing procedures to classify the fire-resistance characteristics of this gypsum panel product or wall assemblies where it is approved for use, refer to GA-600 Fire Resistance and Sound Control Design Manual.