ASTM C1381/C1381M-23

Standard Specification for Molded Glass Fiber Reinforced Gypsum Parts

ABSTRACT
This specification covers molded glass fiber reinforced gypsum (GRG) parts, which are nonload-bearing, thin-shell, ornamental shapes for architectural embellishment of interior building construction. GRG parts shall be produced using the same materials used to make the composites in conformance with the referenced specification. GRG parts shall be manufactured from the mixed slurry or alpha gypsum cement, potable water and additives, and glass fiber reinforcement using either the hand lay-up or the spray-up process in a mold. GRG parts shall be produced according to approved shop drawings. Shop drawings shall specify part dimensions, quantities, recommended attachment points and methods, reinforcements, embedments, and tolerance. The material shall conform to the required mechanical properties and to the specified dimensions and tolerances of GRG parts.
SCOPE
1.1 This specification covers molded glass fiber reinforced gypsum (GRG) parts, which are nonload-bearing, thin-shell, ornamental shapes for architectural embellishment of interior building construction.  
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.  
1.3 The information presented refers to the molded surface of the part.  
1.4 The text of this standard references footnotes, which provide explanatory material. These 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: 28-Feb-2023
• ICS: 91.060.10 - Walls. Partitions. Facades
• 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

• Refers: ASTM C1355/C1355M-96(2020) - Standard Specification for Glass Fiber Reinforced Gypsum Composites
• Effective Date: 01-Jun-2020

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: C1381/C1381M − 23
Standard Specification for
1
Molded Glass Fiber Reinforced Gypsum Parts
This standard is issued under the fixed designation C1381/C1381M; 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* 3.2 Definitions of Terms Specific to This Standard:
3.2.1 control thickness, n—the thickness of the GRG part
1.1 This specification covers molded glass fiber reinforced
where abutting other GRG parts, other products or at fastening
gypsum (GRG) parts, which are nonload-bearing, thin-shell,
points.
ornamental shapes for architectural embellishment of interior
building construction. 3.2.2 embedments, n—materials encapsulated into the part
for the purpose of suspension, attachment, and stiffening.
1.2 The values stated in either SI units or inch-pound units
are to be regarded separately as standard. Within the text, the 3.2.3 finish surface, n—a surface against a mold.
SI units are shown in brackets. The values stated in each
3.2.4 GRG part, n—an individual molded component used
system may not be exact equivalents; therefore, each system
as architectural embellishment.
shall be used independently of the other. Combining values
3.2.5 GRG product, n—combination of GRG parts used as
from the two systems may result in non-conformance with the
architectural embellishment.
standard.
3.2.6 mock-up, n—a presentation assembly of GRG parts
1.3 The information presented refers to the molded surface
defined by the purchase agreement.
of the part.
3.2.7 part thickness, n—thickness of a part at any measure-
1.4 The text of this standard references footnotes, which
ment point.
provide explanatory material. These footnotes shall not be
considered as requirements of the standard.
4. Materials and Manufacture
1.5 This international standard was developed in accor-
4.1 Materials—GRG parts shall be produced using the same
dance with internationally recognized principles on standard-
materials used to make the composites in conformance with
ization established in the Decision on Principles for the
Specification C1355/C1355M.
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
4.2 Manufacture:
Barriers to Trade (TBT) Committee.
4.2.1 GRG parts shall be manufactured from the mixed
slurry of gypsum cement, potable water and additives, when
2. Referenced Documents
used, and not less than 5 % by weight glass fiber reinforcement
2
2.1 ASTM Standards:
using either the hand lay-up or the spray-up process in a mold.
C11 Terminology Relating to Gypsum and Related Building
4.2.2 GRG parts shall be produced according to approved
Materials and Systems
shop drawings.
C1355/C1355M Specification for Glass Fiber Reinforced
4.2.3 Shop drawings shall specify part dimensions,
Gypsum Composites
quantities, recommended attachment points and methods,
3. Terminology reinforcements, embedments, and tolerance.
3.1 Definitions—Definitions of terms shall be in accordance
5. Mechanical Properties
with Terminology C11.
5.1 GRG parts shall be made from materials to make
1
This specification is under the jurisdiction of ASTM Committee C11 on
composites having properties in accordance with Specification
Gypsum and Related Building Materials and Systems and is the direct responsibility
C1355/C1355M.
of Subcommittee C11.01 on Specifications and Test Methods for Gypsum Products.
Current edition approved March 1, 2023. Published March 2023. Originally
approved in 1998. Last previous edition approved in 2018 as C1381/
6. Dimensions and Tolerances of GRG Parts
C1381M – 97 (2018). DOI: 10.1520/C1381_C1381M-23.
2
6.1 Part Thickness—The thickness of the GRG part shall be
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
3
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
not less than ⁄16 in. [5 mm].
Standards volume information, refer to the standard’s Document Summary page on
5
the ASTM website. 6.2 Control Thickness, shall be not less than ⁄16 in. [8 mm].
*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
1

---------------------- Page: 1 ----------------------
C1381/C1381M − 23
6.3 Straightness—At any point on a line generally along a 10. Rejection and Rehearing
plane, an edge, or a surface, the molded side of the part shall
10.1 Rejection of GRG parts th
...

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: C1381/C1381M − 97 (Reapproved 2018) C1381/C1381M − 23
Standard Specification for
1
Molded Glass Fiber Reinforced Gypsum Parts
This standard is issued under the fixed designation C1381/C1381M; 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 Scope*
1.1 This specification covers molded glass fiber reinforced gypsum (GRG) parts, which are nonload-bearing, thin-shell,
ornamental shapes for architectural embellishment of interior building construction.
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the SI units
are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used
independently of the other. Combining values from the two systems may result in non-conformance with the standard.
1.3 The information presented refers to the molded surface of the part.
1.4 The text of this standard references footnotes, which provide explanatory material. These 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
2.1 ASTM Standards:
C11 Terminology Relating to Gypsum and Related Building Materials and Systems
C1355/C1355M Specification for Glass Fiber Reinforced Gypsum Composites
3. Terminology
3.1 Definitions—Definitions of terms shall be in accordance with Terminology C11.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 control thickness, n—the thickness of the GRG part where abutting other GRG parts, other products or at fastening points.
3.2.2 embedments, n—materials encapsulated into the part for the purpose of suspension, attachment, and stiffening.
1
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 Oct. 1, 2018March 1, 2023. Published October 2018March 2023. Originally approved in 1998. Last previous edition approved in 20132018 as
C1381/C1381M – 97 (2013).(2018). DOI: 10.1520/C1381_C1381M-97R18.10.1520/C1381_C1381M-23.
2
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
1

---------------------- Page: 1 ----------------------
C1381/C1381M − 23
3.2.3 finish surface, n—a surface against a mold.
3.2.4 GRG part, n—an individual molded component used as architectural embellishment.
3.2.5 GRG product, n—combination of GRG parts used as architectural embellishment.
3.2.6 mock-up, n—a presentation assembly of GRG parts defined by the purchase agreement.
3.2.7 part thickness, n—thickness of a part at any measurement point.
4. Materials and Manufacture
4.1 Materials—GRG parts shall be produced using the same materials used to make the composites in conformance with
Specification C1355/C1355M.
4.2 Manufacture:
4.2.1 GRG parts shall be manufactured from the mixed slurry of alpha gypsum cement, potable water and additives, when used,
and not less than 5 % by weight glass fiber reinforcement using either the hand lay-up or the spray-up process in a mold.
4.2.2 GRG parts shall be produced according to approved shop drawings.
4.2.3 Shop drawings shall specify part dimensions, quantities, recommended attachment points and methods, reinforcements,
embedments, and tolerance.
5. Mechanical Properties
5.1 GRG parts shall be made from materials to make composites having properties in accordance with Specification
C1355/C1355M.
6. Dimensions and Tolerances of GRG Parts
3
6.1 Part Thickness—The thickness of the GRG part shall be not less than ⁄16 in. [5 mm].
5
6.2 Control Thickne
...