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Review industry standards for gypsum board finish with the Tech Talk information
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Revisiting the Levels of Gypsum Board Finish
By George M. Kutcher, Jr., CDT, CSI
Revisiting GA 214-96: 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.
Click here to download an electronic copy of the revised version from 2007, GA-214-07: "Recommended
Levels of Gypsum Board Finish". For additional information, call 1-800-NATIONAL®
(800-628-4662).
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