AWI e-briefs - 08/19/2010 (Plain Text Version)

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Standards

Did You Know...about the AWS?

By Shows Leary, AWI Quality Certification Program Inspector

Familiarity with the AWI Architectural Woodwork Quality Standards Illustrated (QSI) can no longer be relied on in woodwork project specifications where the Architectural Woodwork Standards (AWS) introduced in August 2009 supercede the QSI. Don’t assume the standards are the same. Learn about factory finishing of architectural woodwork.

Finishing
Section No. 5 of the AWS includes several techniques for factory finishing of architectural woodwork which were not addressed in AWS' predecessor, the QSI.

One of the most often overlooked parts of factory finishing is the sample process. Part 4, Rules (page 110), contains the requirements for finish samples including minimum sizes, labeling criteria, and their purpose. The sample submittal preparation process is one of the most important steps of the finish process.

As you should recall in the QSI, the TYPE system was eliminated and the systems were simply called by their names, such as Conversion Varnish, Acrylic Lacquer, etc. The AWS method of identification is "Systems" followed by the numbers 1 through 13 (The list starts on page 115). New to the lineup are finishing systems formulated to help with specifications requiring LEED® (Leadership in Energy and Environmental Design) Green Building Rating System™ of the U.S. Green Building Council: Water Based Acrylic, UV Curable Polyester, and Water-Based Polyurethane.

Page 106 of the General Section includes a General Performance Characteristics table. The table provides information on the durability, reparability, abrasion resistance, and other abuse-related conditions for each system. For example, System No. 7, catalyzed vinyl, is ranked high for reparability, while System 13, Catalyzed Polyester, is ranked lowest. Therefore, in a low-impact area where repairs may be required, such as high wall panels or ceiling trim, catalyzed vinyl is a reasonable specification. On the other hand, catalyzed polyester, though not very repairable, is ranked among the highest in overall durability. UV curable polyester might therefore be a good choice for a desk front or baseboard.

Page 107 of the General Section includes a Specific Performance Characteristics table. This table allows the design professional to specify finish systems based on common product types that could affect a fine factory finish. For instance, System No. 1, Nitrocellulose Lacquer, is the least resistant to isopropyl alcohol, while System No. 9, UV Curable Polyester, is among the most resistant to isopropyl alcohol. Part 4 also contains definitions of various types of finish defects that can help determine what went wrong or help determine if various defects are permitted per the AWS.

Part 4.2.1 (page 113) summarizes the requirements for back sealing of finished woodwork. In the AWS, premium grade casework requires one coat (1 mil dry) of back sealing. This is not a requirement for custom grade. However, in both premium and custom grades, standing and running trim must be back sealed with at least one coat (1 mil dry) and wall panels must be back sealed with two coats (2 mil dry).

Part 4.3.1.5 (page 115) defines the steps required for each type of finish. It is also broken down into wood characteristics such as opened and closed-grained woods.  Part 4.3.15 (page 115) describes each step required for each of the 13 systems. For example, a premium grade stained post catalyzed lacquer stained and filled finish on an opened grained wood, such as Red Oak requires the following steps: Vinyl wash coat; Stain; Filler; Vinyl sealer; First topcoat; and Second topcoat.

About the author: Shows Leary has been an AWI Quality Certification Program (QCP) inspector since 1996. He has served as QCP's Regional Representative and as a member of the Quality Certification Corporation Board of Directors and Board of Appeals. He is an alternate member of the AWI Technical Committee. Contact Shows Leary at shows@showsleary.com.

Please see cautionary AWI statement in the right-hand column. 

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