Revisiting GA 214: Recommended Levels of Gypsum Board Finish
In 1990, four major trade associations, the Association of Wall and Ceiling Industries International (AWCI), the Ceilings and Interior Systems Construction Association (CISCA), the Gypsum Association (GA), and the Painting and Decorating Contractors of America (PDCA), presented the consensus document Levels of Gypsum Board Finish. The document was created to "precisely describe" the desired finish of walls and ceilings prior to final decoration. This precise description enables contractors to better understand the requirements of architects and building owners in order to enhance the satisfaction of the client. Specifications that include the Levels of Gypsum Board Finish also promote competitive bidding that allows the bidder to consider the correct labor and materials to finish the wall suitably for its final decoration.
The Gypsum Association published GA 214-90: Recommended Specifications: Levels of Gypsum Board Finish. The document has been promoted heavily to specification writers nationwide by local wall and ceiling associations and gypsum manufacturers. As a result of this, GA 214-90 is a Referenced Standard in AIA, MASTERSPEC. The Levels of Gypsum Board Finish are specifically outlined in Section 09255, Gypsum Board Assemblies; Part 3 Execution, in the article titled "Finishing Gypsum Board Assemblies. SPEC System," also references GA 214-90.
A modified version of Levels of Gypsum Board Finish has been incorporated into ASTM C 840, "The Standard Specification for Application and Finishing of Gypsum Board." Included as Appendix X8, The Levels of Finish could even be incorporated into model building codes that utilize ASTM standards as reference documents. Publication in ASTM C 840 will increase the industry's awareness and acceptance of these standards. In 1996, the above-mentioned trade associations published a revised version of the Levels of Gypsum Board Finish, titled GA 216-96: Recommended Levels of Gypsum Board Finish. The revisions are intended to clarify the operations required to fulfill the requirements of each level of finish. Additionally, changes have been made to further define the "skim coat" operation and clearly define "drywall primer".
Many of today's project manuals include references to the Levels of Gypsum Board Finish. Specifiers should be aware of the recommended level of finish required for the final decoration for walls and ceilings and clearly specify this for contract bidders. Bidders should carefully read project specifications to ensure that bidding includes the proper level of finish to meet the standard set for final wall decoration.
Let's review the Levels of Gypsum Board Finish, paying close attention to the document changes:
Level 0
Level 0 is used in temporary construction or if final decoration is undetermined. No taping or finishing is required. Dust walls constructed in mall storefronts are an example of walls finished at level 0. There are no changes in Level 0.
Level 1
A Level 1 finish is recommended in areas that would generally be concealed from view or in areas that are not open to public traffic. In Level 1, "set" has replaced "embedded" so that the first sentence now reads, "All joints and interior angles shall have tape set in joint compound." This was changed to clarify that tape need not be covered with joint compound to fulfill the requirements of Level 1. In Level 1, the surface is left free of excess joint compound. Ridges and tool marks are acceptable for a Level 1 finish. This level is often specified in the plenum area above ceilings, in attics, or in service corridors.
Level 2
In garages, warehouse storage areas and other similar areas where the final surface appearance is not of concern, a Level 2 finish is the recommendation. Level 2 may be specified where moisture resistant gypsum board is used as a tile substrate. Level 2 now reads, "All joints and interior angles shall have tape embedded in joint compound and wiped with a joint knife leaving a thin coating of joint compound over all joints and interior angles". This change is to further differentiate Level 2 from Level 1. Joint compound is applied over all fastener heads and beads. The surface is left free of excess joint compound. Ridges and tool marks are acceptable for a Level 2 finish.
Additionally, Level 2 now includes the following sentence: "Joint compound applied over the body of the tape at the time of tape embedment shall be considered a separate coat of joint compound and shall satisfy the conditions of this level." This sentence also appears in the ASTM C840 Appendix. In the past there has been some confusion as to whether tape pressed into joint compound and covered with joint compound in a single operation fulfilled the requirements of Level 1 or Level 2. This statement is intended to clarify the requirements of Level 2.
Level 3
In areas to be decorated with a medium or heavy texture or where heavy-grade wall coverings will become the final decoration, a Level 3 finish is recommended. Level 3 now states, "All joints and interior angles have tape embedded in joint compound and one additional coat of joint compound applied over all joints and interior angles. Fastener heads and accessories shall be covered with two separate coats of joint compound. All joint compound shall be smooth and free from tool marks and ridges." Before final decoration it is recommended that the prepared surface be coated with a drywall primer prior to the application of final finishes. Level 3 is not recommended where smooth painted surfaces or light- to medium-weight wall coverings become the final decoration.
Level 4
If the final decoration is to be a flat paint, light texture or lightweight wall covering, a Level 4 finish is recommended. Level 4 has been modified to read, "All joints and interior angles have tape embedded in joint compound and two separate coats of joint compound applied over all flat joints and one separate coat of joint compound applied over interior angles. Fastener heads and accessories shall be covered with three separate coats of joint compound. All joint compound shall be smooth and free from tool marks and ridges." Before final decoration it is recommended that the prepared surface be coated with a drywall primer prior to the application of final finishes. Gloss, semi-gloss and enamel paints are not recommended over a Level 4 finish.
Level 5
Level 5 finish is recommended for areas where severe lighting conditions exist and areas that are to receive gloss, semi-gloss, enamel or non-textured flat paints. Level 5 requires all the operations in Level 4. Additionally, a thin skim coat of joint compound, or material manufactured especially for this purpose, is applied to the entire surface. (This definition is referenced to Terminology, Section II, Page 2 of GA-214 to make the description of "skim coat" clear to all.) The surface is smooth and free from tool marks and ridges. Before final decoration it's recommended that the prepared surface be coated with a primer prior to the application of final finishes. The Level 5 finish is required to achieve the highest degree of quality by providing a uniform surface and minimizing the possibility of joint photographing and/or fasteners "burning through" the final decoration.
It is important to consider that each level of finish as described in the recommendation is intended to stand alone. The levels are not intended to be cumulative. In other words, you do not add levels together to achieve the next higher level of finish.
Careful attention should be given to the "'Note" following Levels 3, 4, and 5: "It is recommended that the prepared surface be coated with a "drywall primer" prior to the application of final paint. See painting specification in this regard." This is an important step that should not be forgotten before final decoration. "Drywall primer" replaced the term "primer/sealer" throughout the revised document. The application of high quality, high solids drywall primer minimizes most decorating problems.
As defined in the recommendation, a drywall primer is a paint material specifically formulated to fill the pores and equalize the suction difference between gypsum board surface paper and the compound used on finished joints, angles, fastener heads and accessories, and over skim coatings.
Download an electronic copy of the latest version from Gypsum Association, GA-214 "Recommended Levels of Gypsum Board Finish". For additional information, call 1-800-NATIONAL® (800-628-4662).
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