All Things Gypsum: Keeping Current with Technical Publications
In our March 2008 column, we discussed the ever-growing online library of technical documents published by the Gypsum Association. All of these documents are available via free download from our Web site at www.gypsum.org/download.html. To restate one of the major points made in that column, one of our most important roles in the industry is that of providing the most current technical information on gypsum products to three target audiences: contractors, design professionals, and building officials. To ensure that these audiences are using the most current version of our technical documents, we have included in the latest round of documents language recommending that users check our Web site for a listing of the most recent versions of our technical documents, and we have added a page on our Web site specifically for that purpose at www.gypsum.org/currenteditions.html.
Yet we know that people get busy, especially when trying to drum up business during a tightening economy, and we know that going to our Web site for random updates is probably not among the top ten most important things a drywall contractor sets out to do on any given day. We also know that Walls & Ceilings has a loyal readership comprised of the best informed contractors in the business, so we’re going to use this opportunity to recap the publications we’ve updated during 2008 and touch on the topics these documents cover.
Each of the documents discussed below has been recently reviewed by the Gypsum Association’s Technical Committee and updated to comply with the most current industry standards. The Technical Committee is comprised of technical experts from each of the association’s member companies, several of whom are recipients of PhD degrees in their respective fields. These experts participate in ANSI, ASTM, and other standards writing bodies as well as the model building code process. Before a Gypsum Association technical document is published or updated, it must meet the strict scrutiny of these industry experts who are tasked with ensuring that the document reflects the most current and accurate information available on the topics it addresses. Each document is reformatted to appear in a uniform layout so that users can easily find the information they seek.
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GA-222-08, “Repairing Screw or Nail Pops,” explains that fastener pops are caused by one of several conditions including shrinking lumber, loose attachment of a gypsum panel product, twisted or improperly installed framing, improper fastener length, and improper fastener installation. The document then provides step-by-step instructions for correcting surface irregularities resulting from fastener pops. GA-222-08 also includes graphics that illustrate how wood framing with high moisture content and overly long fasteners can produce fastener pops. The revised version of GA-222 offers new illustrations and metric equivalents.
GA-224-08, “Installation of Predecorated Gypsum Board,” provides essential information regarding pre-decorated gypsum board, including the applicable ASTM and other standards, definitions of terms used throughout the document, delivery, identification, handling, and storage measures, favorable environmental conditions, materials used in building systems that incorporate pre-decorated gypsum board, and proper application methods and procedures. The document also provides additional application, maintenance, and repair information in its appendices. The revised version includes new reference standards and updated metric conversions.
GA-225-08, “Repair of Fire-Rated Gypsum Board Systems,” provides step-by-step instructions and photographic examples of how to properly repair damaged areas smaller than 100 square inches in fire-rated gypsum board assemblies. This document also provides recommendations for repairing damaged areas larger than 100 square inches in gypsum board assemblies, staggering joints in multi-layered systems, and improving the aesthetic appearance of unsightly but structurally sound gypsum board assemblies. The revised version of GA-225 offers new illustrations and updated text.
GA-226-08, “Application of Gypsum Board to Form Curved Surfaces,” describes proper materials and procedures necessary for both dry and wet bending of gypsum board to form either convex or concave curved surfaces. The document also discusses the application of gypsum board in archways and techniques for finishing gypsum board once it has been used to create a curved surface. The revised version of GA-226 offers new illustrations and instructions on preventing unwanted mold growth.
GA-229-08, “Shear Values for Screw Application of Gypsum Board on Walls,” presents shear values achieved using a variety of gypsum board thickness, screw types, and screw patterns. The shear values are displayed in a table that shows board thickness, board orientation, screw type, edge screw spacing, field screw spacing, average ultimate shear, and the applicable test report title. Shear values were determined through a series of tests conducted according to the method set forth in ASTM E 72, “Standard Test Methods of Conducting Strength Tests of Panels for Building Construction.” The document also provides the following conclusions reached after extensive testing of the different attachment configurations: Shear values are comparable for both Type S and W screws; shear values for parallel application exceed those for perpendicular application; shear values for 5/8-inch (15.9 mm) gypsum board exceed those for 1/2-inch (12.7 mm) gypsum board; shear values increase with closer spacing of perimeter fasteners; and when compared to other shear test results, shear values for screws are higher than for nails. The revised version of GA-229 has been reformatted for easier reading.
GA-234-08, “Control Joints for Fire-Resistance Rated Systems,” provides the Gypsum Association’s recommendations for the installation of control joints in the following building systems: the base building structure, uninterrupted walls or partitions, interior ceilings with perimeter relief, interior ceilings without perimeter relief, exterior ceilings and soffits, where ceiling framing changes direction, and surfaces where architectural features occur. GA-234 also provides generic details for control joints in the following conditions: 1-Hour Wall and Partitions Systems, 2-Hour Wall and Partition Systems, and a 1-Hour Floor-Ceiling System with Suspended Ceiling. The revised version of GA-234 offers clarification regarding the distances between joints and metric equivalents.
GA-605-08-08, “Proprietary Gypsum Panel Products for Use in UL Classified Systems,” contains tables listing the proprietary products of participating association members that are mentioned by type in the Underwriters Laboratory Fire Resistance Directory. This document is updated quarterly by the Association and is made available so that contractors, design professionals, and building officials can determine which of the currently available gypsum panel products meets the product requirements set forth in the approved fire resistance-rated designs published in the UL directory. This document was introduced this year in response to requests from design professionals for a quick cross-reference guide for identifying the products called out in the UL directory.
CANADIAN FRENCH VERSIONS
We have also been made aware that several of our technical documents have become required reading in the French-speaking areas of Canada. (Anyone who has driven through Canada lately has observed that highway signs are presented in both English and French, as are product labels.) In response to requests by our Canadian members, we have translated into Canadian French and posted in PDF format on our Web site the following technical documents:
GA-214-07, Niveaux Recommandés De Finition Des Plaques De Plâtre (Recommended Levels of Gypsum Board Finish). This document was first created in the early 1990s to spell out how many coats of joint compound and joint tape are necessary to achieve the desired final gypsum board finish before decorating. Prior to the publication of this document, contractors were expected to provide a “workmanlike finish” with no real guidance beyond that as to how to meet that expectation. Today, this document enables contractors to provide exactly what specifiers call for.
GA-216-07, Pose Et Finition De Plaques De Plâtre (Application and Finishing of Gypsum Panel Products). This document provides the most recent industry recommendations for the application and finishing gypsum panel products, from framing alignment and fastener spacing to multilayer and renovation applications.
GA-801-07, Manipulation Et Entreposage De Plaques De Platre: Un Guide Pour Les Distributeurs, Les Détaillants Et Les Entrepreneurs (Handling And Storage Of Gypsum Panel Products: A Guide For Distributors, Retailers, and Contractors). This document provides guidelines for safely shipping, storing, and handling gypsum panel products in both the supply yard and the job site.
These Canadian French versions can be found on both our download page: www.gypsum.org/download.html, and a page specifically dedicated to Canadian French documents at www.gypsum.org/canadianfrench.html.
As anyone can see, the Gypsum Association has stayed busy getting our online library current during 2008. With 2009 right around the corner, we have several more documents in the works, so stay tuned. W&C