ASTM C931/C931M-98

Standard Specification for Exterior Gypsum Soffit Board

SCOPE
1.1 This specification covers exterior gypsum soffit board, designed to be used for exterior soffits and carport ceilings that are completely protected from contact with liquid water.
Note 1--Specification C840 contains application procedures for exterior gypsum soffit board.
1.2 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.

General Information

• Status: Historical
• Publication Date: 09-May-2001
• 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

• Replaced By: ASTM C931/C931M-01 - Standard Specification for Exterior Gypsum Soffit Board
• Effective Date: 10-May-2001

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: C 931/C 931M – 98
Standard Specification for
Exterior Gypsum Soffit Board
This standard is issued under the fixed designation C 931/C 931M; 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 (e) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope (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
1.1 This specification covers exterior gypsum soffit board,
with exterior gypsum soffit board joints staggered 16 in. (406
designed to be used for exterior soffits and carport ceilings that
mm) on each side of the partition and tested in accordance with
are completely protected from contact with liquid water.
Test Methods E 119.
1.2 The values stated in either inch-pound units or SI
3.3 Gypsum soffit board shall have a maximum flame-
(metric) are to be regarded separately as the standard. Within
spread classification of 25 when tested in accordance with the
the text, the SI units are shown in brackets. The values stated
requirements of Test Method E 84.
in each system shall be used independently of the other. Values
from the two systems shall not be combined.
4. Physical Properties
2. Referenced Documents 4.1 Flexural Strength:
4.1.1 Specimens shall be tested in accordance with Test
2.1 ASTM Standards:
Methods C 473. When tested face up and when tested face
C 473 Test Methods for Physical Testing of Gypsum Panel
down the specimens shall have an average breaking load of not
Products
less than the following:
C 645 Specification for Nonstructural Steel Framing Mem-
Method A Method B
bers
Thickness, Load, lbf (N) Load, lbf (N)
C 1264/C 1264M Specification for Sampling, Inspection,
in. (mm) Load, lbf (N) Bearing Edges Load, lbf (N) Bearing Edges
Rejection, Certification, Packaging, Marking, Shipping, Bearing Edges Parallel to Bearing Edges Parallel to
Across Fiber Fiber of Across Fiber Fiber of
Handling, and Storage
of Surfacing Surfacing of Surfacing Surfacing
E 84 Test Method for Surface Burning Characteristics of
Building Materials ⁄2 (12.7) 110 (489) 40 (178) 107 (476) 36 (160)
⁄8 (15.9) 150 (668) 50 (222) 147 (654) 46 (205)
E 119 Test Methods for Fire Tests of Building Construction
and Materials
4.2 Humidified Deflection:
4.2.1 When tested in accordance with Test Methods C 473,
3. Materials and Manufacture
specimens taken from the gypsum soffit board shall have an
3.1 Gypsum soffit board shall consist of an incombustible
average deflection of no more than the following:
core, essentially gypsum, surfaced with paper bonded to the
Humidified Deflection,
core.
Thickness, in. (mm) Eighths of an in. (mm)
3.2 Exterior gypsum soffit board, Type X (special fire-
⁄2 (12.7) 7 (22)
resistant) designates exterior gypsum soffit board complying
⁄8 (15.9) 4 (13)
with this specification that provides not less than 1-h fire-
5 3
resistance for boards ⁄8-in. (15.9-mm) thick or ⁄4-h fire-
4.3 Core, End, and Edge Hardness:
resistance for boards ⁄2-in. (12.7-mm) thick, applied parallel
4.3.1 When tested in accordance with Test Methods C 473,
with and on each side of load bearing 2 by 4 wood studs spaced
specimens taken from the gypsum soffit board shall have an
16 in. (406 mm) on center with 6d coated nails, 1 ⁄8-in.
average hardness of not less than 15 lbf (67 N) when tested by
Method A and 11 lbf (49 N) when tested by Method B for the
1 core, ends, or edges.
This specification is under the jurisdiction of ASTM Committee C-11 on
Gypsum and Related Building Materials and Systems and is the direct responsibility 4.4 Nail Pull Resistance:
of Subcommittee C11.01 on Specifications and Test Methods for Gypsum Products.
4.4.1 When tested in accordance with Test Methods C 473,
Current edition approved April 10, 1998. Published December 1998. Originally
specimens taken from the gypsum soffit board shall have an
published as C 930–80. Last previous edition C 930–97.
average nail pull resistance of not less than the following:
Annual Book of ASTM Standards, Vol 04.01.
Annual Book of ASTM Standards, Vol 04.07.
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C 931/C 931M
mm), inclusive, with permissible variations of 6 ⁄4 in. (6 mm)
Method A Method B
Thickness, Nail Pull Resistance, Nail Pull Resistanc
...