Painting/coating a roof

[rrman61]

I have a galvanized steel roof on a barn that’s rusting in spots.I plan to use ospho to neutralize the rust.it’s just surface rust and doesn’t leak.I do not want to replace the roof.painting or coating is what I would like to do.would cool seal work? I live in the Deep South

 

[300jk]

I have a galvanized steel roof on a barn that’s rusting in spots.I plan to use ospho to neutralize the rust.it’s just surface rust and doesn’t leak.I do not want to replace the roof.painting or coating is what I would like to do.would cool seal work? I live in the Deep South

Not familiar with cool seal. Would a product like black fibered roof coating work ? Doesn’t cure hard and may give enough movement for expansion and contraction.

 

[300jk]

I have a galvanized steel roof on a barn that’s rusting in spots.I plan to use ospho to neutralize the rust.it’s just surface rust and doesn’t leak.I do not want to replace the roof.painting or coating is what I would like to do.would cool seal work? I live in the Deep South

won’t let me say the name. Black is the first word. Jack is the second.

 

[wp6529]

Henry Tropicool is popular if a bit pricey and works well. I have about 650sf coated with it and when applying in TX summer heat and sun I did temp checks with IR therm and noted ~25F temp reduction. Easy to apply with a roller, easy to repair or recoat as needed.

 

[Duner Wi]

I have standing seam ridge tin roofs that I apply fibered aluminum roof coating. In my opinion not all fibered aluminum roof coating is created equal though it pretty much looks the same in container.

 

[kencombs]

I had the same issue 3 years ago. Solid but rusty roof on a 30x60 building. Looked at the coatings and came to the conclusion that it was too close to the cost of replacement to do that. ( might make a different decision today with the current cost of metal) And, corrugated metal almost demands an airless spray to get good coverage without using way too much material. And a sprayer that will handle that material is really expensive.

Bottom line, I used Rustoleum rusty metal primer and coated with white Rustoleum. So far, so good.

 

[caterpillar guy]

We use the aluminum fibered roof coating on a few roofs over the years. I just bought several 5 gallon pails of it at an auction for about half of the cost of new according to the product number and what I could find it for online.

 

[showcrop]

I have a galvanized steel roof on a barn that’s rusting in spots.I plan to use ospho to neutralize the rust.it’s just surface rust and doesn’t leak.I do not want to replace the roof.painting or coating is what I would like to do.would cool seal work? I live in the Deep South

I would say yes. When I googled it I got a bunch of different products and almost all were Acrylic. I just got done prepping and painting my house. When it was painted 25 years ago they used acrylic paint. That stuff is tough! On the north and west it was still in very good condition. On the East and South the wood surface had deteriorated more from the weather, but the old paint was still tough. Killing the rust with Ospho is the right thing to do. after applying it aggitate it with a stiff bristle brush to help it to penetrate.

 

[Fred Werring]

I would say yes. When I googled it I got a bunch of different products and almost all were Acrylic. I just got done prepping and painting my house. When it was painted 25 years ago they used acrylic paint. That stuff is tough! On the north and west it was still in very good condition. On the East and South the wood surface had deteriorated more from the weather, but the old paint was still tough. Killing the rust with Ospho is the right thing to do. after applying it aggitate it with a stiff bristle brush to help it to penetrate.

Do you guys let it rain to rinse off excess phosphoric acid, wash it, or just paint over the top after it dries.

 

[showcrop]

Do you guys let it rain to rinse off excess phosphoric acid, wash it, or just paint over the top after it dries.

I absolutely would try to remove the excess. How I went about it would depend on how high the eaves are.

 

[Barts Dad]

My Mother used to have an all metal storage shed that had a very rusty roof that had a few seam leaks. I bought a gallon of what Menards sold as a sealer for house trailer roofs. It was silver in color once you stirred it thoroughly. It was a tar based material that I put on with a four inch paint brush. When she sold the house eight years later the roof still looked good and never did leak. Wore an old long sleeved t shirt and my oldest pair of jeans along with double layer nitrile gloves. It was pretty nasty stuff to clean up, ended up throwing away both t shirt and old blue jeans as I knew the stuff would really make a mess in the washer.

 

[Geo-TH,In]

I have a galvanized steel roof on a barn that’s rusting in spots.I plan to use ospho to neutralize the rust.it’s just surface rust and doesn’t leak.I do not want to replace the roof.painting or coating is what I would like to do.would cool seal work? I live in the Deep South

We used Kool seal on my sister's galvanized roof in Leesburg Fl. I found things at Walmart online. I think lowes sells it too.

Kool Seal Elastomeric Roof Coating,4.75 gal $234​

Good stuff. Much better than using aluminum mixed with tar.. Much cooler too.