Undercoater and Primer Sealer

Hi Erin, Look further down on this page and you will see a long discussion about the difference between primers, sealers and undercoaters. If your product is a primer, a product that improves adhesion, it falls under the GS-11 flat or non-flat paint limits. If your product is one which prevents bleed thru from the substrate or provides a smooth surface, then it could be considered a sealer or undercoater, respectively, and use SCAQMD 1113. Your product is obviously trying to cover all the bases. I'd consider the primary attributes it claims and your use in the field against the VOCs it contains. You may be able to make a case for either category depending on those things.

Hi Michelle, Please see my long response to the primer and sealer question in the string you mentioned below. I can't find anything in the 1993 GS-11 edition that indicates primers are part of its scope. Am I missing something? It appears we're getting an uptick on coatings inquiries as more 2009 system projects come to fruition. I hope to address some of the confusion in conversations with USGBC staff.

Hi Dwayne, No, GS-11 1993 doesn't address primers, though GS-11 2008 and 2011 do. That's our problem. GBCI has changed the primer requirement for LEED 2009 by addendum to require us to use GS-11 for primers rather than SCAQMD 1113. V4.0 will fix this when we begin to use a newer GS-11 standard. But for right now, we're all in a painful struggle between definitions. If we can make a manufacturer data based claim for sealer or undercoater, we can likely use the Sealer and Undercoater category in Rule 1113. In other words, we need to see the right words and attributes that speak to the differences in those definitions. If however it's a primer, it needs to meet the GS-11 flat/non-flat limits. I am seeing a whole lot of primers that are flat but exceed 50 g/l, and that's where it all started for me.