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Galvanneal/Paint compatibility

2006

My name is Jamie Tiegs and I am a Project Manager for a construction company in Olympia, Washington.

We have some custom galvanneal metal base that has been cleaned and painted with Kelly Moore #1630 Kel-Cote semi-gloss alkyd enamel. Our Architect has deemed this to be an incompatible situation and that the paint will "sizzle" in the future. Please advise if this is accurate.

Thank You,

Jamie Tiegs
construction - Olympia, Washington

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The A/E is correct in that the galvanized surface will eventually cause the paint to bubble up as time wears on.
You need to get the Kelly Moore factory Rep. (not some sales rep to counter with a Paint SYSTEM .
I have been in construction for over 40 years and I can tell you that painting over hot dipped galv is a futile effort . Our Architects down here have not learned and probably never will. Send your Architect to TEXAS.
It is my opinion that Hot Dipped Gal. is the most premier coating and to attempt to hide or cover this coating is just throwing more money at something that is already the best in corrosion.
What is needed is some-one to come up with different coloring of HD Galv. to satisfy architectural aesthetics.

Wayne Henderson
Senior Inspector - Bastrop, Texas
2006

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Unless I'm on the wrong page, galvanneal and galvanized are 2 different things. We paint galvanneal all of the time.

Sheldon Taylor
supply chain electronics
Wake Forest, North Carolina
2006

I have a new horse trailer steel frame with galvanneal panels. I would like to keep it looking new: however, the nature of transporting horses dictate that I will be forever touching up the paint. What would be the best paint to use for adhesion? What about prep?

PAT KNIGHT-BURRIS
BUYER - GLASGOW, Kentucky
April 27, 2010

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Hi, Pat. As Sheldon notes, galvanneal does not offer the adhesion problems that galvanized does. Further, as the owner of the trailer, your needs are not as dramatic as someone's who ships a product and it must work for years; you are not on the hook for thousands or millions of dollars if you have a problem :-)

Starting with a primer made for galvanized metal should be fine. If it's not decorative enough, you can top the primer with just about any paint you wish except epoxy because a trailer is out in the sun and epoxy has no UV resistance.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
April 27, 2010

You should never put an alkyd enamel over and zinc or zinc containing product. Both Galvanneal and Galvanized products are zinc-containing. When an alkyd comes in contact with zinc it results in a chemical reaction called "saponification" Which means a soap layer forms between the alkyd and the zinc. Delamination of the coating is inevitable. One would question why you would paint galvanized metal but if you do, you should put down a two part epoxy first and then topcoat.

Jeff Deas
- Dunwoody, Georgia USA
September 16, 2011