The root cause is poor adhesion which could be for several reasons between the original paint and the metal you will never stop this roof from peeling unless it is cleaned entirely down to bare metal before it is repainted.
How to strip paint off metal roof.
The results will most likely satisfy you.
Here s how it works.
Also check in advance with your local authorities about any municipal regulations regarding scraping and repainting a metal roof.
Using a disposable paintbrush apply the chemical paint stripper to the metal and let it set according to the instructions on your.
Once you ve coated a good area use a scraper to chip off the paint.
You can cover a precise surface area with a quick application of the product leaving it to do its work.
Once you notice the paint starting to peel away carefully scrape off the loosened paint while the hardware remains in the try or pie pan.
If possible sandblast your roof.
Although it isn t recommended to use a metal implement to scrape the roof it was the only way to remove the loose rust and old paint.
At that point it would need a primer and a top coat.
Within ten minutes the detached paint on the tin roof can literally be peeled away with a paint scraper.
The only real drawbacks with sandblasting involve the time and money required to make use of it.
Be extremely careful not to pierce the metal when scraping.
Sometimes you need to strip paint.
Sandblasting the same technique used to strip rust and paint off automobiles when restoring them works just as well on metal roofing.
Make sure to wear gloves and be careful not to burn yourself.
Pour a little stripper into a non reactive container such as metal or glass.
If you re using a slow cooker or pan you can remove the hardware from the water before scraping.
Sand the entire metal roof surface very lightly with your wire brush or sandpaper.
Apply the stripper to the metal in small slow strokes so you don t splash the abrasive stripping agent.
Scrape off the paint.
Give it a few minutes and you should begin to see the paint bubbling off the galvanized metal.