Author |
Message |
Nathan Woods, CCCA, LEED AP Senior Member Username: nwoods
Post Number: 310 Registered: 08-2005
| Posted on Monday, September 14, 2009 - 12:17 pm: | |
I have a public bid project that specified PPG Duranar for a metallic flake finish over coil and extruded metal and aluminum materials. There is a LOT of coated material on this project. The project is located very near the ocean (within sight of water). The contractor has submitted a substitution for Valspar, and I am looking for tangible feedback from others about the merits of one verses the other. Specifics: - Duranar system is a 4 coat system comprised of A) Primer coat, B) Barrier coat, C) Finish/Color coat, D) Clear top coat. The finish color coat is true metal flake. - Valspar system is a 3 coat product (no barrier coat) and uses mica instead of metal flake. The colors are similar enough that if used uniformly, is not a significant factor in this consideration. Cost is a factor. The 4 coat metallic Duranar is a change from an originally specified 3 coat non-metallic Duranar finish. The Valspar system is thought to be a no-cost change, whereas the 4 coat Duranar reflects a cost increase to the client. What are your thoughts? |
Lynn Javoroski CSI CCS LEEDŽ AP SCIP Affiliate Senior Member Username: lynn_javoroski
Post Number: 928 Registered: 07-2002
| Posted on Monday, September 14, 2009 - 12:19 pm: | |
What length warranty did you specify and will the Valspar system match it? |
Nathan Woods, CCCA, LEED AP Senior Member Username: nwoods
Post Number: 311 Registered: 08-2005
| Posted on Monday, September 14, 2009 - 12:26 pm: | |
20 years and both MFR's have agreed to that duration in the various submittal data I have recieved thus far. |
Ralph Liebing, RA, CSI Senior Member Username: rliebing
Post Number: 1057 Registered: 02-2003
| Posted on Monday, September 14, 2009 - 12:29 pm: | |
Why was the original 3-coat system changed to 4-coat? If for added protection then your criteria changed. And the cost would naturally change too. Isn't the more valid comparison between the two 3-coat systems? Does Valspar have a 4-coat system for the comparison? Proof of equivalency lies with the contractor requesting the substitution-- cost is NOT the only factor [as I am sure you well know] |
Nathan Woods, CCCA, LEED AP Senior Member Username: nwoods
Post Number: 312 Registered: 08-2005
| Posted on Monday, September 14, 2009 - 12:42 pm: | |
The origionally specified finish was a solid color, not metalic. 3 coat is adequate for the origional color/finish. When it changed to metalic, Duranar said a 4 coat is required for their product. I have sufficient history with PPG applications to approve it without any qualms. I do not have a similar history or familarity with Valspar. The technical comparisons appear similar other than the points I listed above. I do not know what the impact those differences will have. This is a public bid project, I have very limited abilitiy to hold a spec on an item where equivlants are allowed by law. As stated above, there is a substantial amount of coated material on this project. A failure would be unimaginably expensive to repair. It is difficult to accept and approve one over the other based on technical data alone. I rarely specifiy products based soley on technical data. |
Lynn Javoroski CSI CCS LEEDŽ AP SCIP Affiliate Senior Member Username: lynn_javoroski
Post Number: 929 Registered: 07-2002
| Posted on Monday, September 14, 2009 - 12:48 pm: | |
Aesthetics are a consideration, but if Owner and designer approve, that becomes a non-issue. The major concern is the durability, which you have addressed with the 20 year warranty, to which both manufacturers agree. Do they both state that harsh environments (salt water) are OK with the specific system? You might start additional research here: http://www.linetec.com/Paint/types_of_paint.htm Linetec in an applicator of many forms of coatings and in the mid-west, considered one of the best. |
Richard L Matteo, AIA, CSI, CCS Senior Member Username: rlmat
Post Number: 347 Registered: 10-2003
| Posted on Monday, September 14, 2009 - 06:22 pm: | |
Nathan, I generally don't specify more than a 3 coat system and haven't heard of any issues yet. In fact, most of what I specify for extrusions is 2-coar Duranar Sunstorm with the clear topcoat for areas subject to human contact. Coil coating is a little different animal Are you sure about the 20 year warranty for extrusions? AAMA 2605 only goes up to 10 years. |
Anne Whitacre, FCSI CCS Senior Member Username: awhitacre
Post Number: 903 Registered: 07-2002
| Posted on Tuesday, September 15, 2009 - 02:27 pm: | |
the products are comparable, especially with the same warranty. in the original Duranar, the metallic "color" comes from metal flakes and its necessary to have a topcoat on that product to prevent corrosion. if the Valspar is using Mica, then corrosion isn't a problem with that formulation. I've generally taken that substitution if the designers like the valspar product -- the Duranar four-coat is a little more subtle and on some projects the designers care about that. |