Household Paint Tips: What To Do When Paint Peels From Galvanized Metal

If the paint on your galvanized roof or spouting is peeling, you'll need to fix the problem before they rust and need to be replaced.

All surfaces, no matter what type of material they are made of, need to be free from dirt, dust, and other debris before they can be painted. However, galvanized metal is a special type of surface that needs some additional care before it can be painted.

Galvanized metal is used most often to make downspouts, gutters, flashings and metal roofs for homes as well as other buildings. This material is actually iron or steel that is coated at the factory with a thin, invisible layer of zinc. The zinc helps to protect the metal from rusting due to exposure in inclement weather. Unfortunately, the zinc coating also prevents paint from adhering properly to the galvanized metal too. Here is an important tip: when this type of metal is installed, it needs to be properly cleaned before it can be painted. Proper cleaning will remove the oily residue that is left on the metal after it has been galvanized.

If you have downspouts, gutters, flashings or metal roofs that the paint is peeling off of, the cause could very well be that they were not cleaned before they were painted. Or, maybe the metal wasn't primed, or primed with the right product, so the paint would adhere. A third reason might be because water froze on them in the winter months. The freezing and expanding action could have caused the paint to peel also.

In order to "fix" the peeling paint on any galvanized metal, you will first need to strip the surface right down to the bare metal. Any paint that hasn't peeled yet will probably do so sooner or later.

So, why not remove it now before it can give you problems later? You certainly don't want the old paint to peel up underneath the fresh coats of paint that you are going to apply. Here is a helpful tip: you can use a heat gun to remove the paint, or you can use a power sander on the galvanized metal. Be sure that you remove any rust that might have accumulated on the metal as well. Steel wool pads work well in removing rust.

The next step is to clean the galvanized metal with a TSP (Tri-Sodium Phosphate) product. You can purchase this product at most home supply stores. The phosphate will remove any zinc coating, et cetera, that might be on the metal. Follow the manufacturer's directions on the container in order to achieve the best results. Rinse the metal thoroughly, then allow the surface to dry.

Now, you will need to apply a good - quality primer that is specially made for galvanized metal. These primers can be purchased in white, gray, and red colors. They can be applied with a paintbrush or a roller can be used on large areas, such as roofs. Remember this tip: be sure that you follow the manufacturer's directions on the container in order to achieve the best results. And, choose a dry, cool, quiet day on which to do this so the primer will dry properly.

Finally, after the primer is dry, it is time to apply a good - quality topcoat of paint to the galvanized metal on your downspouts, gutters, flashings and roofs. Here is a valuable tip you can use: if you live in a hot, sunny climate, your best choice would be to purchase and use an acrylic urethane or a silicone alkyd type of paint. Otherwise, you can use any acrylic paint that is recommended for use on galvanized metal. Some paints that contain a high amount of zinc are also suitable for this purpose. Some of these paints don't require that you use a primer underneath.

After the painting is finished, allow the galvanized metal to dry undisturbed.

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