Paint peeling randomly

Mark Tucker
9/16/2014
I looked at a metal roof for an Architect and School District. It was installed about 10 years ago. Hunter Green. There is obvious cuts in some areas, it appears by a knife blade. Those areas of rust are discernable. Other areas, the rust seems to develop for no reason. No cuts or scrapes in the panels. No obvious hail damage. This is a large metal roof on this school, and it seems to be all over, in no particular pattern. There is also paint peeling from the hemmed edge of the female of the SSR. It's leaving a line of rust run off on the panel. As a long time Architectural Sheet Metal Worker, and being involved in management of a contractor, as well as a Sales Rep, since 2006, I've only seen instances of rust from various reasons. The most common were from scratches, shavings left on the panel, and sparks from a cut off saw, if the panels standing on end in the bundle, were in direct line of the worker cutting the panel. I've seen the problems with Royal Blue, from the early 2000's from one manufacturer. Not anything from this manufacturer of this project, in Hunter Green. The School district has gone back to the manufacturer. Who sent them a letter, telling them the rust was caused from the scratches during installation. And their not going to cover the issue, and have instructed the School District a prescriptive method of repair. Are there any other issues that could cause paint to pop off and rust like this? Back wash coat, bad primer, wrong primer, etc..? Trying to help them get some resolve, without pointing out the actual manufacturer.
Eric Novotny
An informed customer is the Best Customer!
9/17/2014
At the end of the day, any number of things (most of which you mentioned) can cause paint failure. The pattern and location of the rust as you have indicated will give you a better window into how the rust started. Can you post up some pictures?
Mark Tucker
9/17/2014
Unfortunately, I converted to PDF's and deleted the jpg. Do you have an email address?
Mark Tucker
9/17/2014
Here you go.
Mark Tucker
9/17/2014
Another
Mark Tucker
9/17/2014
3rd
Mark Tucker
9/17/2014
last one. This occurs on all sides of the building.
Eric Novotny
An informed customer is the Best Customer!
9/19/2014
Opening up for discussion. I will defer to the manufacturing guys on this one.
Guest User
9/30/2014
That looks like paint system failure to me does the manufacturer warranty the paint system or an outside company. In my case the company I work for has the company that applies the paint system inspect the paint, this includes testing to see if it's going to be warrantied. The first and third picture showing the paint peeling off the tight bent edges was happening to us years ago. We noticed it pretty quickly and remedied the issue before it got out of hand.
Todd Miller
Isaiah Industries, Inc.
9/30/2014
There are a series of tests which can be done on the panels and the paint system to determine the cause of this issue. Do you know if those have been done?
Mark Tucker
9/30/2014
There has not been any testing done. The manufacturer has absolved themselves from doing anything to help the school district. I've been in the Architectural Metal business for over 30 yrs. I've seen various reasons for rust to randomly on a roof. This is 10 yrs old. They said in the last year, this started developing. As I don't represent any metal roofing manufacturers, they figured I had no skin in the game. However, I've never seen any testing on paint adhesion. Only on color match. I'd be interested to hear of those tests, and who can do them?
Mark Tucker
9/30/2014
The paint on the tight bends. although you may have fixed them, what could have caused this? Bundling of the panels, rubbing during transit, and hoisting? Or too tight of bend, with paint that couldn't handle the stress of the rollforming?
Todd Miller
Isaiah Industries, Inc.
9/30/2014
Mark, it's also possible this was an improper use of the paint system, Can you call me next week please? I'd like to discuss this all further and see how I can help but I am out of the office this week. Todd Miller 1-800-543-8938 ext 201
Guest User
9/2/2017
Our metal rust spots (which are all over our roof that that was installed in 2202) look almost identical to the ones that Mark Tucker has posted. Does Mark or anyone of the forum moderators know the name of the metal roof manufacturer and / or the name of the company that painted the coil stock from which the rusting roof metal was made (Clad Tex Metals, etc.)?
Guest User
9/2/2017
Todd, Our roofing manufacturer readily admits that our extensive rusting roof problem originated (from their point of view) with poor prep of the anti-corrosion film that was applied unevenly prior to the primer coat and Trinar top coats being applied. Our roof, installed in the fall of 2002, was made from coil stock that was painted by Clad Tex Metals (now out of business). You mention in one of the posts above that testing that can be done to determine the cause of the metal roof rusting? Who would be contact to have them do this testing? Is this a test that we can ask the manufacturer to perform, since their plant is on our small Maine town in southwestern Maine. Is this testing something that should be really be done by a third-party, such as an independent engineering company rather the manufacturer? Is there a specific ASTM test method? Could I call you to discuss this at the 800-543-8938 ext 201 number you list above? Thank you. Craig Whitaker / 207-233-7527
Todd Miller
Isaiah Industries, Inc.
9/2/2017
Thanks Craig. You're welcome to call me. I will be in the office after Monday. However, the testing I was talking about (typically done by a paint supplier) would basically be to verify what they have already admitted to -- a lack of sufficient pre-treatment on the metal. The question for you, with Clad-Tex no longer around, is whether there is any warranty liability out there. The fault of a problem like this is typically with the actual coil coater -- the company that roll coated the metal. I am not certain but I do not believe that Clad Tex had a coating line. I may be mistaken but I think someone else did the painting for them. If that is the case, that company may hold warranty liability.

If you would like to reply to this thread, please log in. If you do not have an Ask the Experts forum user account, create one here.

Find a Contractor

Get Started Today

Take the first step to increasing the value of your home with a great looking, durable, fire resistant and energy efficient metal roof. Browse our list of qualified MRA Member Roofing Contractors in your area for a free consultation and estimate.