Steel garage doors are some of the most durable and affordable doors out there. They are notoriously hard to polyurea, but if done properly they can be very pleasing to the eye. Like everything else that’s painted, but especially metal, the paint will start chipping and peeling off. When this happens there are a couple of basic things that you need to know in order to restore it to its previous finish.
Steel is not a textured metal and paint needs to something to adhere to in order to get good coverage. For this reason, steel garage doors need several coats in order to look good. In order to perform this repair well, you’ll need the following:
First, you need to identify all of the areas that are peeling. On steel garage doors, all of these areas may not be readily visible. So, using your paint scraper, go over the entire door. This will reveal all of the areas that are either peeling already or have bubbled and will start to peel soon. Remove as much of the paint as will come off, but don’t gouge into your door.
Once you’ve removed as much paint as will readily come off, make sure that the remaining paint is even with the door. Take care in this inspection of the door, as you could wind up with raised areas and lines; that could give you an undesirable finish and make your door appear sloppy. But this process also gives your door less texture to adhere to, so using your sandpaper, rub the bare metal until you begin to feel a texture forming. Don’t be afraid to sand into the remaining paint. This will help to bevel the edges and blend them into the steel. This may take several attempts, but it’s better to take longer and get it right than to be left with a substandard finish.
The scraping and sanding of your garage door is going to leave behind bits of paint and metal, most often in the form of a fine dust. Paint will not adhere to dust, and if applied now, it will give your door and uneven look and texture. Plus, it will probably flake off in about a week. To prevent this, use your gallon of warm water with dish soap in it and your sponge to thoroughly wash the door. The water should be soapy, to help get all of the dust and dirt off of your door. You want to make sure that the door is complete clean before you begin to paint. Once satisfied, use your clean rag to dry your garage door.
Now we come to actually painting the steel garage door, but there are some things that you should consider if you’re not using leftover paint from the original job. You want your paint job to last as long as possible, so protection is your main concern (outside of color) when choosing what kind of paint to use. You can use either latex or oil, and both have their benefits.
Oil based paints will usually help resist rusting and give a smooth, even textured look. Unfortunately, they run and can leave unsightly drips all over the door if not applied properly. Most people tend to use latex paint, which is probably what’s already on your door; it’s always a good idea to match it as closely as possible, so if you think it’s latex then use that. Luckily, latex has a lot of benefits. Exterior latex paints are made to be put in full sunlight, so they will resist fading longer. All paints fade in sunlight, and some colors fade faster than others. Use high quality acrylic latex house paint or 100% acrylic paint. The acrylic polymers in this paint are the most sunlight resistant paint available. Of course, you can use latex and oil paints together, but there are rules.
Latex paint can go over oil paints, because it seals it in keeps it from cracking. But if you apply oil based paint over latex paint, the oil paint will crack over time because the two expand and contract at different rates. After you’ve decided what kind of paint you want, consider the gloss level of the paint you’re choosing. Flat paint hides defects better than glossy paints, but it also has a tendency toward forming a chalky, dusty surface and can leave streaks. Flat paints will also absorb fingerprints and dirt into the paint. Glossy paints are easier to clean and reflect more light which helps with keeping your garage cool.
Once you’ve weighed all the options, and your garage door is sanded and cleaned, simply apply the paint as you would any another. Fill in the patches on your door and makes sure that you’re getting an even distribution over the surface of the door. Blend the paint with the existing coat until you have a smooth finish.