Posts: 12,050
Threads: 1,611
Joined: Jan 2001
Location: Kansas City, Kansas
Watched three companies try to paint the metal overhead garage doors on the building where I used to work. Galvanized metal. All of the companies media blasted the old(first company blasted off 20 year old paint, subsequent removals were less than 2 years old) paint and sprayed on new. Procedure was blast, wash, dry, prime, paint.
As evidenced, none of the three jobs lasted more than two years.
Our company painters finally had time to do the job and did the same procedure. That was in 1997 or 98. Paint is still there as far as I know.
Point being, it is possible to repaint metal surfaces. Only way to insure a good job is to inspect a companies previous work for longevity.
Posts: 12,608
Threads: 0
Joined: Aug 2003
Location: Wapakoneta, OH
Not sure about DIY, but the farmers around me have their metal roofs (barns, machine sheds, etc.) repainted as routine maintenance. It seems to last a good long time, and look good (for a barn) as well. Like Mac said, it's possible...maybe try to find such a painter (the companies doing this are mostly painting contractors that have bucket trucks and suitable spray equipment) and gte an estimate, along with exactly what he plans on usiong for the coating.
I started with absolutely nothing. Now, thanks to years of hard work, careful planning, and perseverance, I find I still have most of it left.
Posts: 5,653
Threads: 0
Joined: May 2005
Location: Centre County Pennsylvania
usually, a good paint job on metal involves a primer. I guess everyone tries to avoid that for metal roofs. A lot of primers need to be top-coated soon after drying, that's also a problem for roofs.
Posts: 18,559
Threads: 0
Joined: Jul 2006
Location: Milwaukee area
They painted the metal roof in a shopping center where I was renting space. This was about twenty years ago.
The guys performing the work started one evening as the shops closed up.
They had a couple of bucket trucks and lights and worked into the evening, spraying the roof.
When it got dark, the metal cooled off and water started to condense. But the paint hadn't set yet.
Giant globs of dripping blue (blue paint + water) mess ran down the roof, onto the walkway and the parking lot below.
What a mess.
Posts: 36,556
Threads: 3
Joined: Nov 2004
Location: RTP, NC
I've seen it done to the metal (old tin) roofs on some of the farm houses and barns here. The few times I watched it done they did it with rollers, not spraying.
Posts: 584
Threads: 0
Joined: Jul 2004
GAF has an entire list of specialty coatings one of which was developed to apply over kynar finished metal roofs. I believe they have several others as we'll. Also check out acrymax and weather barrier. All these are not dig though
Posts: 13,412
Threads: 0
Joined: Jun 2004
Location: Texas
08-11-2016, 06:12 PM
(This post was last modified: 08-11-2016, 06:13 PM by daddo.)
Is it galvanized under the paint? If so, I would hate to have that coating damaged or removed, then you'll have to keep painting the rust spots that poke through the new paint no matter what you do.
Posts: 5,119
Threads: 12
Joined: Apr 2009
Location: SoMar
Most of you are missing the fact that factory made metal roofing is most likely powder coated. It has been for better than 30 years. I know. I looked into in for my 2nd house. And my 3rd house too.
And no, you can't simply paint over powder coat. Primer or not.
It is what it is. Live with it, or replace it for no good reason if it's not leaking.
