ASTM WK43453

    Work Item: ASTM WK43453 - Revision of C1063 - 12c Standard Specification for Installation of Lathing and Furring to Receive Interior and Exterior Portland Cement-Based Plaster

    (What is a Work Item?)

    Active Standard: C1063 - 14a

    Developed by Subcommittee: C11.03 | Committee C11 | Contact Staff Manager



    1. Rationale

    Multi-part prevision, including the following rationale: Exterior soffits adjacent to soffit corners where a soffit meets an adjacent exterior wall are defined as weather exposed surfaces in the building code which require weather protection. A soffit drip screed provides the first line of protection at those conditions. Water-related damage and surface staining to the soffit can be minimized with a soffit drip screed. See also the concurrent C926 ballot item for A2.2.3 deleting the obsolete drip edge requirement that this new paragraph 6.33 will replace. Exterior soffits adjacent to soffit corners where a soffit meets an adjacent exterior wall, are defined as weather exposed surfaces in the building code which require weather protection. A soffit drip screed provides the first line of protection at those conditions. Water-related damage and surface staining to the soffit can be minimized with a soffit drip screed. See also the concurrent C926 ballot item for A2.2.3 deleting the obsolete drip edge requirement that this new paragraph 6.33 will replace. This revision replaces ambiguous terminology with accepted terminology for clarity. The word tied in 7.10.1.5 can be misinterpreted to incorrectly mean nailed, screwed or stapled. Throughout C1063, the words tie, tied and ties always require wire, and refers to wire tie and are never associated with or used to describe a staple, nail or screw fastener attachment. This proposed revision simply adds one word to clarify the intent of the word tied to prevent future misinterpretations. 7.11.4.1 only pertains to control joints, defining allowed panel area criteria between control joints. The phrase in parenthesis (expansion and contraction) confuses this paragraph which solely regards control joints. The word expansion as used here may confuse the user by suggesting that this paragraph applies to expansion joints, which is not correct, as it only applies to control joints and also erroneously refers to a contraction joint which is not a defined term or joint type in C1063, and a term which also causes confusion.. By definition control joints are to accommodate shrinkage and curing movements and expansion joints accommodate movement beyond plaster shrinkage and curing. The appropriate cement plaster joint over an expansion joint in the base exterior wall (substrate movement) is an expansion joint, not a control joint. This revision clarifies the purpose of the expansion joint and harmonizes this text with its defined function. Fastening at stated intervals (7 in. (178 mm)) is unnecessary and may cause accessory to fall out of alignment. Accessory is not a structural component of the stucco assembly and therefore does not require an aggressive fastening pattern and can be fastened sufficiently so as to be held in place until it is permanently affixed with cement coatings(s). A physical lath example was made and reviewed by the committee at the meeting in Phoenix. (Item submitted by Albert Carrillo). The placing of any interfering materials is recurring with increasing frequency and will impede the embedment and/or mechanical lock of the materials. This item will provide guidance that may avoid failure of the installation or litigation involving the installer


    Keywords

    ceiling; expansion control joints; lath; plaster; screed; suspended ceiling; walls;
    Citing ASTM Standards
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    Work Item Status

    Date Initiated:
    09-20-2013

    Technical Contact:
    Frank Hendron

    Item:
    009

    Ballot:
    C11 (13-06)

    Status:
    Negative Votes Need Resolution

    Item:
    010

    Ballot:
    C11 (13-06)

    Status:
    Negative Votes Need Resolution

    Item:
    012

    Ballot:
    C11 (13-06)

    Status:
    Negative Votes Need Resolution

    Item:
    013

    Ballot:
    C11 (13-06)

    Status:
    Negative Votes Need Resolution

    Item:
    006

    Ballot:
    COS (14-01)

    Status:
    Ballot Item Approved as C1063-2014A and Pending Publication

    Item:
    007

    Ballot:
    C11 (13-06)

    Status:
    Ballot Item Approved as C1063-2014 and Pending Publication

    Item:
    011

    Ballot:
    C11 (13-06)

    Status:
    Ballot Item Approved as C1063-2013 and Pending Publication