American Architectural Manufacturers Association : WCCMC Gets Progress Report on Work Comparing Finishes Standards

January 30, 2017

During the AAMA Fall Conference in Savannah, Wood & Cellulosic Composite Material Council reviewed the work being done in comparing AAMA 653 and WDMA TM-12, in an effort to simplify and align the requirements for WCCMC finishes materials.

653-14, Voluntary Performance Requirements and Test Procedures for Organic Coatings on Wood and Cellulosic Composite Substrates, describes test procedures and performance requirements for organic coatings applied to AAMA Certified Wood and Cellulosic Composite Substrates for windows, doors and similar products. These substrates may be made from wood or cellulosic composites as defined and specified in AAMA 309-04.

TM-12-2014, Test Method for Factory Applied Pigmented Coatings for Wood and Wood Cellulosic Composites Used for Millwork, sets forth a minimum acceptable level of performance with respect to film integrity, exterior weatherability and general appearance without the application of an additional field coating. Also dry film thickness must be specified by the coating manufacturer and measured per ASTM D1005, D7091 or D5235. It assumes that Water Repellent Preservative Treatment and primer coating of Millwork is applied prior to use of all factory-applied pigmented finish coatings.

The overall objective of the task group is to determine where and how these two similar documents might be consolidated in order to eliminate redundancy and the resultant potential confusion within the industry. A possibility is to retire AAMA 653 in favor of WDMA TM-12, so long as AAMA membership agrees that necessary requirements are captured in WDMA TM-12.

The coatings attributes under consideration are:

• Abrasion resistance (currently addressed only in WDMA TM-12)
• Accelerated weathering (currently addressed only in TM-12). It was noted that color change criteria under weathering should match AAMA 623, Voluntary Specification, Performance Requirements and Test Procedures for Organic Coatings on Fiber Reinforced Thermoset Profiles.
• Appearance evaluation (similarly addressed in both documents, but precise viewing conditions should be specified)
• Chemical resistance, including detergent, mortar, muriatic acid and window cleaner (similarly addressed in both documents, except window cleaner, which is addressed only in T.M.-12). The committee is seeking to reconcile references to Hunter vs. CieLab ΔE measurement methods.
• Cleaning protocols (currently addressed only in 653, but simply refers to manufacturer instructions)
• Cold Crack Cycle testing (currently addressed more substantively in 653)
• Color samples (currently addressed only in 653)
• Color uniformity (visual inspection) (currently addressed more substantively in 653)
• Initial dry film thickness (currently addressed more substantively in 653)
• Dry film adhesion of thin (<125 microns) and thick (≥125 microns) coatings after test (WDMA T.M.-12 makes no thickness distinction)
• Wet film adhesion (currently addressed in both documents, although only T.M.-12 references an ASTM test method)
• Heat build-up (currently addressed only in 653)
• Humidity Resistance (currently addressed only in 653)
• Impact resistance (currently addressed in both documents)
• Outdoor weathering effects on film integrity, color retention and chalking (currently addressed in both publications but more substantively in 653)
• Oven aging (currently addressed only in 653)
• Paint block test (currently addressed only in T.M.-12)
• Sealant compatibility (currently addressed only in 653)
• Specimen quantity required for evaluation (currently addressed in both documents although different quantities are specified)
• Specular gloss (currently addressed more substantively in 653; T.M.-12 only defers to manufacturer specs)
• Water repellant treating and primer coating (currently addressed only in T.M.-12 based on I.S.4)

Note that where both documents address the same attribute, there are often nuanced differences in the test method and/or criteria.

The ballot of the draft matrix to the WCC Finishes Committee has been completed. The intent is to approach WDMA to modify their document and sunset the AAMA document. This was successfully balloted to the AAMA Finishes Steering Committee, and is now out for Product Group ballot. Those involved are encouraged to respond to ballot 16-1057 as soon as possible.

back