1、Designation: C 1280 09Standard Specification forApplication of Gypsum Sheathing1This standard is issued under the fixed designation C 1280; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in pare
2、ntheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers the minimum requirements forand methods of application of gypsum sheathing for use as asubstrate for exterior wall claddin
3、g.1.2 Details of construction for a specific assembly toachieve the required fire resistance shall be obtained fromreports of fire-resistance tests, engineering evaluations, orlistings from recognized fire testing laboratories.1.2.1 This specification shall govern where it is morestringent (size or
4、thickness of framing and size and spacing offasteners) than the fire-rated construction.1.3 Where sound control is required for a gypsum sheathingassembly, the details of construction shall be in accordancewith the acoustical test report of an assembly that has met therequired acoustical value(s).1.
5、3.1 This specification shall govern where it is morestringent (size or thickness of framing and size and spacing offasteners) than the sound-rated construction.1.4 Where resistance to racking loads or shear is requiredfor a gypsum sheathing assembly, the details of constructionshall be in accordance
6、 with the racking or shear test report ofan assembly that has met the required racking or shear value(s).1.4.1 This specification shall govern where it is morestringent (size or thickness of framing and size and spacing offasteners) than the racking or shear-tested construction.1.5 The values stated
7、 in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.6 The text of this standard references footnotes whichprovide explanatory material. These footnotes shal
8、l not beconsidered as requirements of the standard.1.7 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of
9、regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C11 Terminology Relating to Gypsum and Related Build-ing Materials and SystemsC 954 Specification for Steel Drill Screws for the Applica-tion of Gypsum Panel Products or Metal Plaster Bases toSteel Studs from 0.033 in. (0
10、.84 mm) to 0.112 in. (2.84mm) in ThicknessC 955 Specification for Load-Bearing (Transverse andAxial) Steel Studs, Runners (Tracks), and Bracing orBridging for Screw Application of Gypsum Panel Productsand Metal Plaster BasesC 1002 Specification for Steel Self-Piercing TappingScrews for the Applicati
11、on of Gypsum Panel Products orMetal Plaster Bases to Wood Studs or Steel StudsC 1007 Specification for Installation of Load Bearing(Transverse and Axial) Steel Studs and Related Accesso-riesC 1063 Specification for Installation of Lathing and Furringto Receive Interior and Exterior Portland Cement-B
12、asedPlasterC 1396/C 1396M Specification for Gypsum Board2.2 U.S. Department of Commerce Publication:PS20 American Softwood Lumber Standard33. Terminology3.1 Definitions: Definitions shall be in accordance withTerminology C11.3.2 Definitions of Terms Specific to This Standard:3.2.1 exterior cladding,
13、 na permanent material or systemthat impedes the transmission of environmental elements to thesheathing.3.2.2 fastener, nnails, staples, or screws used for applica-tion of the sheathing.3.2.3 framing member, nstuds, headers, bracing, andblocking that serve to receive the sheathing.1This specificatio
14、n is under the jurisdiction of ASTM Committee C11 onGypsum and Related Building Materials and Systems and is the direct responsibilityof Subcommittee C11.03 on Specifications for theApplication of Gypsum and OtherProducts in Assemblies.Current edition approved May 1, 2009. Published May 2009. Origin
15、allyapproved in 1994. Last previous edition approved in 2007 as C 1280 07.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe
16、ASTM website.3Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.1*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 1
17、9428-2959, United States.3.2.4 horizontal application, na synonym for perpendicu-lar application.3.2.5 parallel application, ngypsum sheathing appliedwith the edges parallel to the framing members; a synonym forvertical application.3.2.6 perpendicular application, ngypsum sheathing ap-plied with the
18、 edges at right angles to the framing members; asynonym for horizontal application.3.2.7 require, vto mandate by a force outside this speci-fication, such as a building code, project specification, contract,or purchase order.3.2.8 specified, adjpertaining to a mandatory requirementof this specificat
19、ion or a referenced requirement.3.2.9 specify, vto mandate by an obligation of this stan-dard or a referenced document.3.2.10 vertical application, nsynonym for parallel appli-cation.3.2.11 weather resistive barrier, na temporarily exposedprotective membrane that is intended to impede the penetratio
20、nof environmental elements until the installation of a permanentexterior cladding.4. Exposure After Installation4.1 Gypsum sheathing board is a substrate that shall becovered by an exterior cladding or other weather-resistivebarrier and is not intended for long-term exposure. It shall notbe exposed
21、to the elements for more than 30 days after it hasbeen installed. Gypsum sheathing shall be covered with aweather-resistive barrier within 30 days if the exposure timewill be more than 30 days.NOTE 1Some building codes require an additional weather-resistivebarrier. The exterior face paper of the sh
22、eathing shall be dry prior toapplication of the additional weather-resistive barrier.5. Materials and Manufacture5.1 Gypsum SheathingSpecification C 1396/C 1396M.5.1.1 Type X (Special Fire-Resistant) Gypsum SheathingGypsum sheathing that provides a greater degree of fireresistance than regular gypsu
23、m sheathing as defined in Speci-fication C 1396/C 1396M.5.2 FastenersFasteners shall be as described in 5.2.1through 5.2.3. The fastener length shall be not less than thatspecified in Table 1.5.2.1 NailsNails shall be not less than 12-gaugegalvanized,716-in. (11.1-mm) diameter head.5.2.2 Screws:5.2.
24、2.1 Screws for fastening gypsum sheathing to woodframing members, and to steel framing members less than0.033 in. (0.84 mm) in thickness, shall meet the requirementsof Specification C 1002.5.2.2.2 Screws for fastening gypsum sheathing to steelframing members from 0.033 to 0.112 in. (0.84 to 2.84 mm)
25、 inthickness shall meet the requirements of Specification C 954.5.2.2.3 Trim-head screws shall not be permitted for theattachment of gypsum sheathing.5.2.2.4 Screws for fastening self-furred metal lath overgypsum sheathing as described in 8.2.7 shall be as specified inSpecification C 1063.5.2.3 Stap
26、lesStaples shall be of galvanized steel, not lessthan 16-gauge,716-in. (11.1-mm) wide crown outside measure-ment. Legs shall have divergent points.5.3 Framing Members:5.3.1 Wood FramingWood framing members shall con-form to PS20.5.3.2 Steel FramingLoad-bearing steel framing shallmeet the requirement
27、s of Specification C 955.6. Substrate, Surface Preparation6.1 The maximum spacing for framing members for gyp-sum sheathing shall be not more than 24 in. (610 mm) oncenter on walls.6.1.1 Wood framing shall be straight and true, attachedsecurely following accepted engineering practices and asrequired
28、 for the intended design. The surfaces to whichabutting edges or ends of gypsum sheathing are to be attachedshall be not less than 112-in. (38-mm) wide. The bearingsurface shall be not less than34 in. (19 mm) for internalcorners or angles.6.1.2 Load-bearing metal framing members shall be of theprope
29、r size and design for their intended use and shall beinstalled in accordance with Specification C 1007.7. Framing Alignment7.1 Framing members shall be installed so that the surfacewill be in an even plane, unless otherwise specified, after thegypsum sheathing has been applied.8. Cutting and Applica
30、tion of Gypsum Sheathing8.1 Cutting Gypsum Sheathing:8.1.1 The gypsum sheathing shall be cut by scoring andbreaking or by sawing, working from the face side. The facepaper shall be cut with a sharp knife or other suitable tool whencutting by scoring. The gypsum sheathing shall be broken bysnapping t
31、he gypsum sheathing in the reverse direction or bycutting the back paper with a knife or suitable tool.8.1.2 The cut edges and ends of gypsum sheathing shall betrimmed to obtain neat fitting joints when installed.8.1.3 Holes for pipes, fixtures, or other small openings shallbe scored on the face pap
32、er before removing the cutout with asaw or special tool designed for this purpose.8.1.4 Where gypsum sheathing meets projecting surfaces,the gypsum sheathing shall be scribed and cut neatly.8.2 Application of Gypsum Sheathing:8.2.1 Gypsum sheathing shall be fitted snugly around allwindow and door op
33、enings.TABLE 1 Minimum Fastener LengthsFramingTypeFastenerTypeSheathingThickness, in. (mm)MinimumFastenerLength, in. (mm)Wood nails12 (12.7) 112 (38)58 (15.9) 134 (45)screws12 (12.7) 114 (32)58 (15.9) 114 (32)staples12 (12.7) 112 (38)58 (15.9) 134 (45)Steel screws12 (12.7) 1 (25)58 (15.9) 114 (32)C
34、1280 0928.2.1.1 Sheathing joints shall be offset a minimum of 4 in.(100 mm) from the edge of any opening.8.2.1.2 Gypsum sheathing shall be flashed at openings sothat water intrusion will not contact the sheathing.8.2.2 All vertical end and edge joints shall abut over thecenters of framing members an
35、d shall be offset a minimum ofone framing space between adjacent rows of gypsum sheath-ing.8.2.3 Control Joints:8.2.3.1 Control joints shall be provided in wall runs exceed-ing 30 ft (9100 mm) in length. The distance between controljoints shall be not more than 30 ft (9100 mm).8.2.3.2 Control joints
36、 shall be installed in walls whereverthere is a building construction joint or where required.8.2.3.3 The location of the control joints shall be as requiredby either the building design or the exterior cladding specified.8.2.3.4 Control joints, other accessories, and metal plasterbase shall be fast
37、ened through gypsum sheathing to framingmembers.8.2.4 Gypsum sheathing, 4-ft (1220-mm) wide, shall beapplied either parallel or perpendicular to framing members.8.2.4.1 Square edge gypsum sheathing applied perpendicu-lar to framing members shall be covered with a weather-resistive barrier, or horizo
38、ntal joints shall be sealed.8.2.5 Tongue and groove gypsum sheathing shall be appliedwith the long dimension perpendicular to framing members,with the grooved edges down, interlocking the tongue of thepanel below without forcing.8.2.6 Fasteners shall be spaced not more than 8 in. (203mm) on center a
39、long vertical ends or edges and intermediatesupports. The length of fasteners shall be as indicated in Table1.8.2.6.1 Fasteners shall be located not less than38 in. (9.5mm) from the ends and edges of the gypsum sheathing.8.2.6.2 Gypsum sheathing shall be held tight against theframing when driving fa
40、steners.8.2.6.3 Fasteners shall be driven so that the heads are at orslightly below the surface of the gypsum sheathing withoutbreaking the face paper or fracturing the core.8.2.6.4 Screws shall be driven without stripping the framingmember around the screw shank.8.2.6.5 Staples shall be driven with
41、 the crown parallel to theframing member.8.2.7 Application of Gypsum Sheathing Under Self-FurredMetal LathWhere fire resistance or shear resistance is notrequired, and when metal lath and portland cement plaster areto be applied as the exterior cladding over gypsum sheathinginstalled over framing me
42、mbers spaced not more than 16 in.(406 mm) on center, and the metal lath shall be installed inaccordance with Specification C 1063 within 24 h after thegypsum sheathing, the gypsum sheathing shall be permitted tobe applied as specified in 8.2.7.1 and 8.2.7.2, and fastening ofthe gypsum sheathing shal
43、l be completed with the attachmentof the self-furred metal lath.8.2.7.1 For 2-ft (610-mm) wide sheathing installed in ac-cordance with 8.2.5, vertical ends of gypsum sheathing shall befastened in accordance with 8.2.6. Gypsum sheathing shall befastened in place at each intermediate stud with a minim
44、um oftwo fasteners per board spaced not more than 2 in. (50 mm)from opposite edges.8.2.7.2 For 4-ft (1220-mm) wide sheathing installed inaccordance with 8.2.4, vertical ends or edges of gypsumsheathing shall be fastened in accordance with 8.2.6. Gypsumsheathing shall be fastened in place at each int
45、ermediate studwith fasteners spaced not more than 24 in. (610 mm) on center.9. Keywords9.1 exterior walls; gypsum; sheathingSUMMARY OF CHANGESCommittee C11 has identified the location of selected changes to this specification since the last issue,C 1280 04, that may impact the use of this specificat
46、ion. (Approved May 1, 2009)(1) Added new paragraphs 5.2.2.3 and 5.2.2.4.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of
47、 any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments ar
48、e invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not rec
49、eived a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).C 1280 093
