ASTM C1278/C1278M-17

Standard Specification for Fiber-Reinforced Gypsum Panel

ABSTRACT
This specification covers fiber-reinforced gypsum panel. The physical properties, dimensions and tolerances, and edges of interior fiber-reinforced gypsum panels, water-resistant fiber-reinforced gypsum backing panels, exterior fiber-reinforced gypsum soffit panels, water-resistant exterior fiber-reinforced gypsum sheathing panels, interior fiber-reinforced gypsum underlayment panels, and fiber-reinforced gypsum roof board panels are presented in details. The surfaces of the fiber-reinforced gypsum panels shall be true and free from imperfections that would render the panels unfit for use with or without decoration.
SCOPE
1.1 This specification covers fiber-reinforced gypsum panels described in 1.1.1 – 1.1.4.  
1.1.1 Interior Fiber-Reinforced Gypsum Panels  
are designed to be used for walls, ceilings, or partitions and affords a suitable surface to receive decoration.  
1.1.2 Water-Resistant Fiber-Reinforced Gypsum Backing Panels  
are designed primarily to be used as a base for the application of ceramic or plastic tile on walls or ceilings. This product is also suitable for decoration.  
1.1.3 Exterior Fiber-Reinforced Gypsum Soffit Panels  
are designed for use on exterior soffits and carport ceilings that are completely protected from contact with liquid water.  
1.1.4 Water-Resistant Exterior Fiber-Reinforced Gypsum Sheathing Panels  
are designed for use as sheathing on buildings.  
1.1.5 Interior Fiber-Reinforced Gypsum Underlayment Panels
are designed for use as a base for application of finished flooring materials.  
1.1.6 Fiber-Reinforced Gypsum Board Panels
are designed for use in roofing systems.  
1.2 Specifications applicable to all fiber-reinforced gypsum panels are located in Sections 1 – 4 and 11 – 13 except as modified by applicable product sections. Specifications applicable to specific panels are located in the following sections:    
Interior Fiber-Reinforced Gypsum Panels  
5  
Water-Resistant Fiber-Reinforced Gypsum Backing Panels  
6  
Exterior Fiber-Reinforced Gypsum Soffit Panels  
7  
Water-Resistant Exterior Fiber-Reinforced Gypsum Sheathing
Panels  
8  
Interior Fiber-Reinforced Gypsum Underlayment Panels  
9  
Fiber-Reinforced Gypsum Roof Board Panels  
10  
1.3 The values stated in either inch-pound units or SI (metric) are to be regarded separately as the standard. Within the text, the SI units are shown in brackets. The values stated in each system shall be used independently of the other. Values from the two systems shall not be combined.  
1.4 The text of this specification references notes and footnotes that provide explanatory material. These notes and footnotes shall not be considered as requirements of the standard.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 30-Apr-2017
• ICS: 91.100.10 - Cement. Gypsum. Lime. Mortar
• Technical Committee: C11 - Gypsum and Related Building Materials and Systems
• Drafting Committee: C11.01 - Specifications and Test Methods for Gypsum Products

Relations

• Replaces: ASTM C1278/C1278M-07a(2015) - Standard Specification for Fiber-Reinforced Gypsum Panel
• Effective Date: 01-May-2017
• Refers: ASTM E96/E96M-24 - Standard Test Methods for Gravimetric Determination of Water Vapor Transmission Rate of Materials
• Effective Date: 01-Mar-2024
• Refers: ASTM E84-23d - Standard Test Method for Surface Burning Characteristics of Building Materials
• Effective Date: 01-Dec-2023
• Refers: ASTM E96/E96M-23 - Standard Test Methods for Gravimetric Determination of Water Vapor Transmission Rate of Materials
• Effective Date: 15-Nov-2023
• Refers: ASTM E84-23c - Standard Test Method for Surface Burning Characteristics of Building Materials
• Effective Date: 01-Sep-2023
• Refers: ASTM E119-19 - Standard Test Methods for Fire Tests of Building Construction and Materials
• Effective Date: 01-Oct-2019
• Refers: ASTM C473-19 - Standard Test Methods for Physical Testing of Gypsum Panel Products
• Effective Date: 01-Oct-2019
• Refers: ASTM E84-19b - Standard Test Method for Surface Burning Characteristics of Building Materials
• Effective Date: 01-Jul-2019
• Refers: ASTM E84-19a - Standard Test Method for Surface Burning Characteristics of Building Materials
• Effective Date: 15-Apr-2019
• Refers: ASTM E84-19 - Standard Test Method for Surface Burning Characteristics of Building Materials
• Effective Date: 01-Mar-2019
• Refers: ASTM E119-18c - Standard Test Methods for Fire Tests of Building Construction and Materials
• Effective Date: 01-Nov-2018
• Refers: ASTM E119-18ce1 - Standard Test Methods for Fire Tests of Building Construction and Materials
• Effective Date: 01-Nov-2018
• Refers: ASTM E84-18b - Standard Test Method for Surface Burning Characteristics of Building Materials
• Effective Date: 01-Oct-2018
• Refers: ASTM C11-18a - Standard Terminology Relating to Gypsum and Related Building Materials and Systems
• Effective Date: 01-Oct-2018
• Refers: ASTM E119-18b - Standard Test Methods for Fire Tests of Building Construction and Materials
• Effective Date: 01-Sep-2018

Overview

ASTM C1278/C1278M-17: Standard Specification for Fiber-Reinforced Gypsum Panel is an international standard developed by ASTM International. This specification establishes the minimum requirements for fiber-reinforced gypsum panels used in a variety of building applications, including interior walls, ceilings, partitions, exterior soffits, sheathing, underlayment for flooring, and roofing systems. Fiber-reinforced gypsum panels provide enhanced strength, durability, and water resistance compared to conventional gypsum panels. The standard outlines physical properties, dimensions and tolerances, edge profiles, and provisions for both inch-pound and SI measurement units.

Key Topics

• Scope and Types of Panels: Covers a range of gypsum panels including:

  • Interior fiber-reinforced gypsum panels
  • Water-resistant backing panels (for tile substrates)
  • Exterior soffit panels
  • Water-resistant exterior sheathing panels
  • Interior underlayment panels (for finished flooring)
  • Roof board panels

• Physical and Mechanical Properties: Includes criteria for:

  • Flexural strength and resistance to breaking loads
  • Nail pull resistance
  • Humidified deflection and dimensional tolerances
  • Water absorption and resistance
  • Surface burning characteristics (flame spread index)
  • Mold resistance (when specified)

• Dimensional and Quality Requirements:

  • Specified thicknesses and tolerances
  • Panel width, length, and end squareness
  • Edge types: square, beveled, featured, tapered, and combinations
  • Surface quality to ensure suitability for decoration or finishing

• Fire-Resistant (Type X) Panels:

  • Panels identified as Type X meet enhanced fire resistance criteria, suitable for use in applications where additional protection is required.

Applications

Fiber-reinforced gypsum panels specified by ASTM C1278/C1278M-17 are used in many construction and remodeling projects due to their reinforced structure and versatility. Typical applications include:

• Interior Walls and Ceilings: Provides increased strength and superior surface for paint or wallpaper in homes, offices, and commercial buildings.
• Tile Backing Boards: Serves as a durable, water-resistant base for tile installations in bathrooms, kitchens, and utility rooms.
• Exterior Soffits and Sheathing: Utilized in protected outdoor ceiling and wall areas, including soffits and carport ceilings, as well as in wall assemblies that require moisture resistance.
• Floor Underlayment: Offers a stable, smooth base for finished flooring materials such as vinyl, laminate, or carpet tiles in high-traffic areas.
• Roof Decks: Applied in flat or low-slope roofing systems where a gypsum board substrate is required for fire resistance and dimensional stability.

By adhering to ASTM C1278/C1278M-17, designers, builders, and contractors ensure the use of high-quality, reliable materials that meet the demands of modern construction and align with internationally recognized best practices.

Related Standards

The following ASTM standards are referenced within ASTM C1278/C1278M-17 and are relevant for testing, installation, and terminology:

• ASTM C11 - Terminology Relating to Gypsum and Related Building Materials and Systems
• ASTM C22/C22M - Specification for Gypsum
• ASTM C473 - Test Methods for Physical Testing of Gypsum Panel Products
• ASTM C645 - Specification for Nonstructural Steel Framing Members
• ASTM C1264 - Specification for Sampling, Inspection, Packaging, Marking, Shipping, Handling, and Storage of Gypsum Panel Products
• ASTM D1037 - Test Methods for Evaluating Properties of Wood-Base Fiber and Particle Panel Materials
• ASTM D3273 - Test Method for Resistance to Mold Growth
• ASTM E84 - Surface Burning Characteristics of Building Materials
• ASTM E96/E96M - Water Vapor Transmission of Materials
• ASTM E119 - Fire Tests of Building Construction and Materials

Keywords: fiber-reinforced gypsum panels, gypsum board, ASTM C1278, wall board, water-resistant panels, fire-resistant board, roof deck, construction material standards, building codes compliance.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: C1278/C1278M −17
Standard Specification for
Fiber-Reinforced Gypsum Panel
This standard is issued under the fixed designation C1278/C1278M; the number immediately following the designation indicates the
year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last
reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope* 1.4 The text of this specification references notes and
footnotes that provide explanatory material. These notes and
1.1 This specification covers fiber-reinforced gypsum pan-
footnotes shall not be considered as requirements of the
els described in 1.1.1 – 1.1.4.
standard.
1.1.1 Interior Fiber-Reinforced Gypsum Panels are de-
1.5 This international standard was developed in accor-
signed to be used for walls, ceilings, or partitions and affords
dance with internationally recognized principles on standard-
a suitable surface to receive decoration.
ization established in the Decision on Principles for the
1.1.2 Water-Resistant Fiber-Reinforced Gypsum Backing
Development of International Standards, Guides and Recom-
Panels are designed primarily to be used as a base for the
mendations issued by the World Trade Organization Technical
application of ceramic or plastic tile on walls or ceilings. This
Barriers to Trade (TBT) Committee.
product is also suitable for decoration.
1.1.3 Exterior Fiber-Reinforced Gypsum Soffıt Panels are
2. Referenced Documents
designed for use on exterior soffits and carport ceilings that are
completely protected from contact with liquid water. 2.1 ASTM Standards:
1.1.4 Water-Resistant Exterior Fiber-Reinforced Gypsum C11 Terminology Relating to Gypsum and Related Building
Materials and Systems
Sheathing Panels are designed for use as sheathing on build-
ings. C22/C22M Specification for Gypsum
C473 Test Methods for Physical Testing of Gypsum Panel
1.1.5 Interior Fiber-Reinforced Gypsum Underlayment
Products
Panelsaredesignedforuseasabaseforapplicationoffinished
C645 Specification for Nonstructural Steel Framing Mem-
flooring materials.
bers
1.1.6 Fiber-Reinforced Gypsum Board Panels are designed
C1264 Specification for Sampling, Inspection, Rejection,
for use in roofing systems.
Certification, Packaging, Marking, Shipping, Handling,
1.2 Specifications applicable to all fiber-reinforced gypsum
and Storage of Gypsum Panel Products
panels are located in Sections1–4 and11–13 except as
D1037 Test Methods for Evaluating Properties of Wood-
modified by applicable product sections. Specifications appli-
Base Fiber and Particle Panel Materials
cable to specific panels are located in the following sections:
D3273 TestMethodforResistancetoGrowthofMoldonthe
Interior Fiber-Reinforced Gypsum Panels 5
Surface of Interior Coatings in an Environmental Cham-
Water-Resistant Fiber-Reinforced Gypsum Backing Panels 6
ber
Exterior Fiber-Reinforced Gypsum Soffit Panels 7
Water-Resistant Exterior Fiber-Reinforced Gypsum Sheathing 8 E84 Test Method for Surface Burning Characteristics of
Panels
Building Materials
Interior Fiber-Reinforced Gypsum Underlayment Panels 9
E96/E96M Test Methods for Water Vapor Transmission of
Fiber-Reinforced Gypsum Roof Board Panels 10
Materials
1.3 The values stated in either inch-pound units or SI
E119 Test Methods for Fire Tests of Building Construction
(metric) are to be regarded separately as the standard. Within
and Materials
the text, the SI units are shown in brackets. The values stated
in each system shall be used independently of the other. Values
3. Terminology
from the two systems shall not be combined.
3.1 Definitions—Definitions of terms shall be in accordance
with Terminology C11.
This specification is under the jurisdiction of ASTM Committee C11 on
Gypsum and Related Building Materials and Systems and is the direct responsibility
of Subcommittee C11.01 on Specifications and Test Methods for Gypsum Products. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved May 1, 2017. Published May 2017. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 1994. Last previous edition approved in 2015 as C1278/ Standards volume information, refer to the standard’s Document Summary page on
C1278M – 07a (2015). DOI: 10.1520/C1278_C1278M-17. the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1278/C1278M − 17
3.1.1 nominal thickness, n—the manufacturer-stated frac- 5. Interior Fiber-Reinforced Gypsum Panels
tional value of thickness of the gypsum panel product ex-
5.1 Physical Properties of Interior Fiber-Reinforced Gyp-
pressed in decimal value to the nearest one-thousandth (0.001)
sum Panels:
of an inch.
5.1.1 Flexural Strength—The specimens shall be tested face
up and face down. The average breaking load shall be not less
4. Materials and Manufacture
than the following:
4.1 Fiber-reinforced gypsum panels shall consist essentially
Thickness, in. [mm] Method B, lbf [N]
of gypsum with fibers dispersed throughout.
⁄2 [12.7] 110 [490]
4.1.1 Gypsum—Specification C22/C22M.
⁄8 [15.9] 155 [690]
4.1.2 Fibers—Cellulose, derived from paper, paperboard
5.1.2 Humidified Deflection—The specimens shall have an
stock, wood, or other organic material.
average deflection of not more than the following:
4.2 Thebacksurfaceoffoil-backedfiber-reinforcedgypsum
Thickness, in. [mm] Deflection, eighths of an inch, [mm]
panels shall in addition be covered with aluminum foil. ⁄2 [12.7] 3 [10]
⁄8 [15.9] 2 [6]
4.3 Water-resistant fiber-reinforced gypsum panels shall be
5.1.3 Nail Pull Resistance—The specimens shall have an
treated with a material that imparts water resistance through-
average nail pull resistance of not less than the following:
out.
Thickness, in. [mm] Method B, lbf [N]
4.4 Fiber-reinforced gypsum panels, mold resistant, desig-
⁄2 [12.7] 120 [535]
⁄8 [15.9] 145 [645]
nates fiber-reinforced gypsum panels having not more than
20 % mold growth, based on surface area coverage, when
5.2 Dimensions and Tolerances of Interior Fiber-Reinforced
tested in accordance with Test Method D3273.
Gypsum Panel:
5.2.1 Specimens shall be taken from samples in accordance
4.5 Fiber-reinforced gypsum panels, type X (special fire-
with Specification C1264.
resistant)designatesfiber-reinforcedgypsumpanelscomplying
with this specification that provide not less than 1-h fire 5.2.1.1 Specimens shall be tested in accordance with Test
5 3
Methods C473.
resistance rating for panels ⁄8-in. [15.9-mm] thick or ⁄4-h fire
1 5
resistance rating for panels ⁄2-in. [12.7-mm] thick, applied 5.2.2 Thickness—The thickness shall be ⁄2 or ⁄8 in. [12.7 or
parallel with and on each side of load bearing 2 by 4 wood
15.9 mm] with tolerances of 60.015 in. [60.40 mm], and with
studs spaced 16 in. [406 mm] on center with 6d coated nails, a local tolerance of 60.030 in. [60.80 mm].
7 1
1 ⁄8-in. [48-mm] long, 0.0915-in. [2.3-mm] diameter shank, ⁄4-
5.2.3 Width—The width shall be up to 54 in. [1370 mm],
in. [6.4-mm] diameter heads, spaced 7 in. [178 mm] on center
with a tolerance of ⁄32 in. [3 mm] under the specified width.
with fiber-reinforced gypsum panel joints staggered 16 in.
5.2.4 End Squareness—Corners shall be square with a
[406 mm]oneachsideofthepartitionandtestedinaccordance
tolerance of 6 ⁄8 in. [63 mm] in the full width of the panel.
with Test Methods E119.
5.3 Edges—The edges shall be either square, beveled,
NOTE 1—Consult producers for independent test data on assembly
featured, tapered, or featured and tapered.
details and fire resistance ratings for other types of construction. See fire
5.4 Foil-Backed Fiber-Reinforced Gypsum Panels:
test reports or listings from recognized fire testing laboratories for
assembly particulars, materials, and ratings.
5.4.1 Foil-backedfiber-reinforcedgypsumpanelsshallmeet
all of the requirements for fiber-reinforced gypsum panels. In
4.6 Fiber-reinforced gypsum panels shall have a flame
addition, aluminum foil shall be bonded to the back surface.
spread index of not more than 25 when tested in accordance
5.4.2 When tested in accordance with Test Methods E96/
with Test Method E84.
E96M, the permeance of foil-backed fiber-reinforced gypsum
4.7 Physical Properties, Dimensions, and Tolerances of
panels shall be not more than 0.30 perm [17 ng/Pa·s·m ]
Gypsum Panel:
(DesiccantMethod)fortheconditionof50 %relativehumidity
4.7.1 Specimens shall be taken from samples obtained in
on the face of the panel and 0 % relative humidity on the
accordance with Specification C1264.
foil-covered back side of the panel.
4.7.1.1 Specimens shall be tested in accordance with Test
Methods C473.
6. Water-Resistant Fiber-Reinforced Gypsum Backing
4.7.2 Core, End, and Edge Hardness—The specimens shall
Panels
have an average hardness of not less than 20 lbf [90 N] when
tested in accordance with Method B. 6.1 PhysicalPropertiesofWater-ResistantFiber-Reinforced
4.7.3 Edges and Ends—The edges and ends shall be
Gypsum Backing Panels:
straight.
6.1.1 Flexural Strength—The specimens shall be tested face
4.7.4 Length—The nominal length shall be from 6 to 24 ft
up and face down. The average breaking load shall be not less
[1830 to 7320 mm], with a tolerance of 6 ⁄4 in. [6 mm] from
than the following:
the specified length.
Thickness, in. [mm] Method B, lbf [N]
4.7.5 Tapered Edge Depth—The average thickness of the ⁄2 [12.7] 110 [490]
⁄8 [15.9] 155 [690]
edge of recessed or tapered edge shall be not less than 0.020 in.
[0.51 mm] but not more than 0.090 in. [2.29 mm] less than the 6.1.2 Humidified Deflection—The specimens shall have an
average thickness of the fiber-reinforced gypsum panel. average deflection of not more than the following:
C1278/C1278M − 17
7.2.3 Width—The width shall be up to 54 in. [1370 mm],
Thickness, in. [mm] Deflection, eighths of an inch, [mm]
⁄2 [12.7] 3 [10]
with a tolerance of ⁄32 in. [3 mm] under the specified width.
⁄8 [15.9] 2 [6]
7.2.4 End Squareness—Corners shall be square with a
6.1.3 Nail Pull Resistance—The specimens shall have an
tolerance of 6 ⁄8 in. [63 mm] in the full width of the panel.
average nail pull resistance of not less than the following:
7.3 Edges—The edges shall be either square, beveled,
Thickness, in. [mm] Method B, lbf [N]
featured, tapered, or featured and tapered.
⁄2 [12.7] 120 [535]
⁄8 [15.9] 145 [645]
6.1.4 Water Resistance—The specimens shall have an aver- 8. Water-Resistant Exterior Fiber-Reinforced Gypsum
age water absorption of not more than 5 weight percentage Sheathing Panels
after 2-h immersion.
8.1 Physical Properties of Water-Resistant Exterior Fiber-
6.1.5 Surface Water Absorption—The specimens shall have
Reinforced Gypsum Sheathing Panels:
anaveragefacesurfacewaterabsorptionofnotmorethan1.6 g
8.1.1 Flexural Strength—The specimens shall be tested face
after two hours of elapsed time.
up and face down. The average breaking load shall be not less
6.2 Dimensions and Tolerances of Water-Resistant Fiber-
than the following:
Reinforced Gypsum Backing Panel:
Thickness, in. [mm] Method B, lbf [N]
6.2.1 Specimens shall be taken
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: C1278/C1278M − 07a (Reapproved 2015) C1278/C1278M − 17
Standard Specification for
Fiber-Reinforced Gypsum Panel
This standard is issued under the fixed designation C1278/C1278M; the number immediately following the designation indicates the
year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last
reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope*
1.1 This specification covers fiber-reinforced gypsum panels described in 1.1.1 – 1.1.4.
1.1.1 Interior Fiber-Reinforced Gypsum Panels are designed to be used for walls, ceilings, or partitions and affords a suitable
surface to receive decoration.
1.1.2 Water-Resistant Fiber-Reinforced Gypsum Backing Panels are designed primarily to be used as a base for the application
of ceramic or plastic tile on walls or ceilings. This product is also suitable for decoration.
1.1.3 Exterior Fiber-Reinforced Gypsum Soffıt Panels are designed for use on exterior soffits and carport ceilings that are
completely protected from contact with liquid water.
1.1.4 Water-Resistant Exterior Fiber-Reinforced Gypsum Sheathing Panels are designed for use as sheathing on buildings.
1.1.5 Interior Fiber-Reinforced Gypsum Underlayment Panels are designed for use as a base for application of finished flooring
materials.
1.1.6 Fiber-Reinforced Gypsum Board Panels are designed for use in roofing systems.
1.2 Specifications applicable to all fiber-reinforced gypsum panels are located in Sections 1 – 4 and 11 – 13 except as modified
by applicable product sections. Specifications applicable to specific panels are located in the following sections:
Interior Fiber-Reinforced Gypsum Panels 5
Water-Resistant Fiber-Reinforced Gypsum Backing Panels 6
Exterior Fiber-Reinforced Gypsum Soffit Panels 7
Water-Resistant Exterior Fiber-Reinforced Gypsum Sheathing 8
Panels
Water-Resistant Exterior Fiber-Reinforced Gypsum Sheathing 8
Panels
Interior Fiber-Reinforced Gypsum Underlayment Panels 9
Fiber-Reinforced Gypsum Roof Board Panels 10
1.3 The values stated in either inch-pound units or SI (metric) are to be regarded separately as the standard. Within the text, the
SI units are shown in brackets. The values stated in each system shall be used independently of the other. Values from the two
systems shall not be combined.
1.4 The text of this specification references notes and footnotes that provide explanatory material. These notes and footnotes
shall not be considered as requirements of the standard.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
C11 Terminology Relating to Gypsum and Related Building Materials and Systems
C22/C22M Specification for Gypsum
C473 Test Methods for Physical Testing of Gypsum Panel Products
C645 Specification for Nonstructural Steel Framing Members
This specification is under the jurisdiction of ASTM Committee C11 on Gypsum and Related Building Materials and Systems and is the direct responsibility of
Subcommittee C11.01 on Specifications and Test Methods for Gypsum Products.
Current edition approved Dec. 1, 2015May 1, 2017. Published December 2015May 2017. Originally approved in 1994. Last previous edition approved in 20112015 as
C1278/C1278M – 07a (2011).(2015). DOI: 10.1520/C1278_C1278M-07AR15.10.1520/C1278_C1278M-17.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1278/C1278M − 17
C1264 Specification for Sampling, Inspection, Rejection, Certification, Packaging, Marking, Shipping, Handling, and Storage of
Gypsum Panel Products
D1037 Test Methods for Evaluating Properties of Wood-Base Fiber and Particle Panel Materials
D3273 Test Method for Resistance to Growth of Mold on the Surface of Interior Coatings in an Environmental Chamber
E84 Test Method for Surface Burning Characteristics of Building Materials
E96/E96M Test Methods for Water Vapor Transmission of Materials
E119 Test Methods for Fire Tests of Building Construction and Materials
3. Terminology
3.1 Definitions—Definitions of terms shall be in accordance with Terminology C11.
3.1.1 nominal thickness, n—the manufacturer-stated fractional value of thickness of the gypsum panel product expressed in
decimal value to the nearest one-thousandth (0.001) of an inch.
4. Materials and Manufacture
4.1 Fiber-reinforced gypsum panels shall consist essentially of gypsum with fibers dispersed throughout.
4.1.1 Gypsum—Specification C22/C22M.
4.1.2 Fibers—Cellulose, derived from paper, paperboard stock, wood, or other organic material.
4.2 The back surface of foil-backed fiber-reinforced gypsum panels shall in addition be covered with aluminum foil.
4.3 Water-resistant fiber-reinforced gypsum panels shall be treated with a material that imparts water resistance throughout.
4.4 Fiber-reinforced gypsum panels, mold resistant, designates fiber-reinforced gypsum panels having not more than 20 % mold
growth, based on surface area coverage, when tested in accordance with Test Method D3273.
4.5 Fiber-reinforced gypsum panels, type X (special fire-resistant) designates fiber-reinforced gypsum panels complying with
5 3
this specification that provide not less than 1-h fire resistance rating for panels ⁄8-in. [15.9-mm] thick or ⁄4-h fire resistance rating
for panels ⁄2-in. [12.7-mm] thick, applied parallel with and on each side of load bearing 2 by 4 wood studs spaced 16 in. [406 mm]
7 1
on center with 6d coated nails, 1 ⁄8-in. [48-mm] long, 0.0915-in. [2.3-mm] diameter shank, ⁄4-in. [6.4-mm] diameter heads, spaced
7 in. [178 mm] on center with fiber-reinforced gypsum panel joints staggered 16 in. [406 mm] [406 mm] on each side of the
partition and tested in accordance with Test Methods E119.
NOTE 1—Consult producers for independent test data on assembly details and fire resistance ratings for other types of construction. See fire test reports
or listings from recognized fire testing laboratories for assembly particulars, materials, and ratings.
4.6 Fiber-reinforced gypsum panels shall have a flame spread index of not more than 25 when tested in accordance with Test
Method E84.
4.7 Physical Properties, Dimensions, and Tolerances of Gypsum Panel:
4.7.1 Specimens shall be taken from samples obtained in accordance with Specification C1264.
4.7.1.1 Specimens shall be tested in accordance with Test Methods C473.
4.7.2 Core, End, and Edge Hardness—The specimens shall have an average hardness of not less than 20 lbf [90 N] when tested
in accordance with Method B.
4.7.3 Edges and Ends—The edges and ends shall be straight.
4.7.4 Length—The nominal length shall be from 6 to 24 ft [1830 to 7320 mm], with a tolerance of 6 ⁄4 in. [6 mm] from the
specified length.
4.7.5 Tapered Edge Depth—The average thickness of the edge of recessed or tapered edge shall be not less than 0.020 in. [0.51
mm] but not more than 0.090 in. [2.29 mm] less than the average thickness of the fiber-reinforced gypsum panel.
5. Interior Fiber-Reinforced Gypsum Panels
5.1 Physical Properties of Interior Fiber-Reinforced Gypsum Panels:
5.1.1 Flexural Strength—The specimens shall be tested face up and face down. The average breaking load shall be not less than
the following:
Thickness, in. [mm] Method B, lbf [N]
⁄2 [12.7] 110 [490]
⁄8 [15.9] 155 [690]
5.1.2 Humidified Deflection—The specimens shall have an average deflection of not more than the following:
C1278/C1278M − 17
Thickness, in. [mm] Deflection, eighths of an inch, [mm]
⁄2 [12.7] 3 [10]
⁄8 [15.9] 2 [6]
5.1.3 Nail Pull Resistance—The specimens shall have an average nail pull resistance of not less than the following:
Thickness, in. [mm] Method B, lbf [N]
⁄2 [12.7] 120 [535]
⁄8 [15.9] 145 [645]
5.2 Dimensions and Tolerances of Interior Fiber-Reinforced Gypsum Panel:
5.2.1 Specimens shall be taken from samples in accordance with Specification C1264.
5.2.1.1 Specimens shall be tested in accordance with Test Methods C473.
1 5
5.2.2 Thickness—The thickness shall be ⁄2 or ⁄8 in. [12.7 or 15.9 mm] with tolerances of 6 0.015 in. [6 0.40 60.015 in. [60.40
mm], and with a local tolerance of 6 0.030 in. [6 0.80 60.030 in. [60.80 mm].
5.2.3 Width—The width shall be up to 54 in. [1370 mm], with a tolerance of ⁄32 in. [3 mm] under the specified width.
5.2.4 End Squareness—Corners shall be square with a tolerance of 6 ⁄8 in. [6 3 [63 mm] in the full width of the panel.
5.3 Edges—The edges shall be either square, beveled, featured, tapered, or featured and tapered.
5.4 Foil-Backed Fiber-Reinforced Gypsum Panels:
5.4.1 Foil-backed fiber-reinforced gypsum panels shall meet all of the requirements for fiber-reinforced gypsum panels. In
addition, aluminum foil shall be bonded to the back surface.
5.4.2 When tested in accordance with Test Methods E96/E96M, the permeance of foil-backed fiber-reinforced gypsum panels
shall be not more than 0.30 perm [17 ng/Pa·s·m ] (Desiccant Method) for the condition of 50 % relative humidity on the face of
the panel and 0 % relative humidity on the foil-covered back side of the panel.
6. Water-Resistant Fiber-Reinforced Gypsum Backing Panels
6.1 Physical Properties of Water-Resistant Fiber-Reinforced Gypsum Backing Panels:
6.1.1 Flexural Strength—The specimens shall be tested face up and face down. The average breaking load shall be not less than
the following:
Thickness, in. [mm] Method B, lbf [N]
⁄2 [12.7] 110 [490]
⁄8 [15.9] 155 [690]
6.1.2 Humidified Deflection—The specimens shall have an average deflection of not more than the following:
Thickness, in. [mm] Deflection, eighths of an inch, [mm]
⁄2 [12.7] 3 [10]
⁄8 [15.9] 2 [6]
6.1.3 Nail Pull Resistance—The specimens shall have an average nail pull resistance of not less than the following:
Thickness, in. [mm] Method B, lbf [N]
⁄2 [12.7] 120 [535]
⁄8 [15.9] 145 [645]
6.1.4 Water Resistance—The specimens shall have an average water absorption of not more than 5 weight percentage after 2-h
immersion.
6.1.5 Surface Water Absorption—The specimens shall have an average face surface water absorption of not more than 1.6 g
1.6 g after two hours of elapsed time.
6.2 Dimensions and Tolerances of Water-Resistant Fiber-Reinforced Gypsum Backing Panel:
6.2.1 Specimens shall be taken from samples obtained in accordance with Specification C1264.
6.2.1.1 Specimens shall be tested in accordance with Test Methods C473.
1 5 1
6.2.2 Thickness—The nominal thickness shall be ⁄2 or ⁄8 in. [12.7 or 15.9 mm] with tolerances of 6 ⁄64 in. [6 0.4 [60.4 mm],
and with a local tolerance of 6 ⁄32 in. [6 0.8 [60.8 mm].
6.2.3 Width—The width shall be up to 54 in. [1370 mm], with a tolerance of ⁄32 in. [3 mm] under the specified width.
6.2.4 End Squareness—Corners shall be square with a tolerance of 6 ⁄8 in. [6 3 [63 mm] in the full width of the panel.
6.3 Edges—The edges shall be either square, beveled, featured, tapered, or featured and tapered.
7. Exterior Fiber-Reinforced Gypsum Soffit Panels
7.1 Physical Properties of Exterior Fiber-Reinforced Gypsum Soffıt Panels:
7.1.1 Flexural Strength—The specimens shall be tested face up and face down. The average breaking load shall be not less than
the following:
Thickness, in. [mm] Method B, lbf [N]
⁄2 [12.7] 110 [490]
⁄8 [15.9] 155 [690]
7.1.2 Humidified Deflection—The specimens shall have an average deflection of not more than the following:
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