Painting rusty metal roof?

[Ton ton]

Just curious if you guys have a recommendation for painting a rusty metal roof? I'm currently using a fiber - based aluminum paint from ACE hardware. Just curious if you guys are able to find a non- fiber roof paint for a reasonable price. I realize paint availability can be hit or miss these days. I'm putting it on with a brush. Not really interested in dragging a sprayer up on the roof. Anyone have roof painting helpful tips for me? Thank you for your time.

 

[Lou's Garage]

"A million years ago" when I owned a mobile home with a metal roof, we used a product called CoolSeal. I really have no idea what it's made out of, you'll have to check to see if it meets your specs but it really worked well at controlling heat, wind noise, and water leakage. We had a flat roof so application was by roller. If you have a corrugated roof, a roller probably won't work. You've got the right idea with a big brush.

Lou Manglass

 

[jack stand]

If that Ace fibered silver paint is the same thing that we used to call "trailer roof paint" that's about the best. The instructions for prep was just hitting any heavier scaled rust with a wire brush and nothing to a little rust coming through galvanized or paint. A 5 gallon can was about $50.

 

[Ton ton]

Thank you for the informative replies. It's a corrugated roof.

 

[jack stand]

I've had varying results, but as cheap as it is, and virtually no prep, it's easy enough to brush on another layer even if it's a bit premature. I think the one metal roof that I was surprised that either the rust was starting to show through or the "finish" was getting kinda blotchy still made it 5-6 years.
My goal was to preserve the metal rather than aesthetics.

 

[mogandave]

If it's rusty I would treat it with OSPHO first.

 

[Ton ton]

If it's rusty I would treat it with OSPHO first.

What is OSPHO?

 

[tncatadjuster]

It‘s an acid that turn rust into another compound that is no longer acting like rust and will accept paint.

 

[Ton ton]

It‘s an acid that turn rust into another compound that is no longer acting like rust and will accept paint.

Thank you.

 

[ng8264723]

OSPHO was available at ACE a few years ago

 

[mogandave]

It is a truly great product. It “converts” the rust to a black coating.

It is (or at least was) cheap and easy to use, and goes really far. It is very thin brushes well. I have also sprayed it with great results but I would not spray it again without coveralls and a full-face respirator.

Great for dipping parts as well.

Ospho Rust Treatment - Since 1947

Ospho rust treatment has been killing rust in the Marine, Industrial and Automove fields since 1947

www.ospho.com

 

[strutaeng]

Is installing a new galvalume R panel an option?

How much area are you talking about here?

 

[Ton ton]

Is installing a new galvalume R panel an option?

How much area are you talking about here?

2 poultry houses. 440 ft. long and 70 ft. wide .

 

[mogandave]

Wow, that’s a good bit of roof.

I would mop it with OSPHO. If you don’t mind the black it will last a couple years, or you can re-coat it with most any exterior paint.

 

[dutchgray]

A coat of bitumen was the traditional farmer fix where I am for a rusty tin roof.

 

[cpttuna]

google flat roof doctor. watch his videos and you may pick up some ideas.

 

[Firebrick43]

I now its been a while but ospho can be sprayed on with a cheap 1 gallon garden sprayer and tossed after your done.

The best paint over rusty metal I have seen is an aluminized moisture cured urethane.

The only problem with moisture cured urrethane is that once you open it you pretty much have to use it. You can gas it with an unlit propane torch before closing the lid if you want to use it up in a few days. Lay wax paper over it before putting the lid back on a gallon can if you want to get the lid off again. But I have never been able to keep any long term, it will set up in the can.

 

[rkevins]

what type of buildings do you have, we have 2- 36'x 340' steel truss with 2"x4" purlins built in 1979, the tin was nailed down and the nails started leaking, we pulled most of them and replaced with screws that helped some

 

[willy3486]

I got some roof coating at lowes for mine. It does good and I usually recoat it about every 10 years. I have a few buildings made out of salvaged buildings. It does good for what I need. Be careful of Gypsies if they come through your area. There is a large Gypsy community out east of here that came through years ago. Their MO was usually the same "we are in this area coating a barn up the road and can do you a good deal. " It was watered down paint that would be lucky to last 6 months.

 

[brianh]

OSPHO was available at ACE a few years ago

Still is, just got some 27$ for a gallon

 

[Ton ton]

I got some roof coating at lowes for mine. It does good and I usually recoat it about every 10 years. I have a few buildings made out of salvaged buildings. It does good for what I need. Be careful of Gypsies if they come through your area. There is a large Gypsy community out east of here that came through years ago. Their MO was usually the same "were in this area coating a barn up the road and can do you a good deal. " It was watered down paint that would be lucky to last 6 months.

I'm planning on doing the painting myself. But thank you for the heads up.

 

[Ton ton]

what type of buildings do you have, we have 2- 36'x 340' steel truss with 2"x4" purlins built in 1979, the tin was nailed down and the nails started leaking, we pulled most of them and replaced with screws that helped some

It's screws holding the tin down.

 

[Ton ton]

For those wondering, the rust is fairly mild. But I am hoping to get it painted before the rust gets the upper hand.