Aluminum doors are sturdy, popular, and commonly used for exterior doors such as a wide garage door. So, you might be wondering how to paint your aluminum doors. They are just as vulnerable to fading and natural wear and tear as conventional wooden doors. But they do require a slightly different painting process. We have carefully researched how to properly paint an aluminum door, including large garage doors.
In order to effectively paint any aluminum door, such as broad garage doors, there are a few basic steps you can follow:
- Select the correct paint
- Remove hardware
- Sand and clean
- Tape and prime
Although painting an aluminum door may take some time, the process is relatively simple and does not require challenging tools. Still, aluminum doors require special treatment. Keep reading to learn how to prepare aluminum doors, as well as what kind of primer and paint is best for them.
How to Paint an Aluminum Door
1. Select the Correct Paint
Aluminum doors, like any other metal, are not a porous substance. As such, paint will not soak beneath the surface in the same way it could with traditional wooden doors. Also, metal is uniquely vulnerable to rust, which is the result of oxygen and moisture corroding the metal.
What kind of paint do you use on aluminum doors?
Since metal doors are often used outside, they are subjected to many weather conditions. This is why oil-based paints, designed for exterior use, are typically preferred to latex paints when you work on aluminum doors.
A water-based paint is considered to be easier and safer but isn’t ideal for metal. It can potentially cause rust, and it won’t have the same level of durability. Also, it won’t bond as well as an oil-based alternative.
However, you may also find more specific products, such as a solvent-based DTM paint. These are specially designed to be applied directly to metal and are formulated to protect metal surfaces. It is especially useful for aluminum doors that will need to withstand harsh weather conditions.
Most DTM paints are built to withstand more moisture and UV light. Also, they will often prevent rust, which can create unsightly blemishes and weaken the aluminum door.
Some DTM paint even acts as a two-in-one primer and paint combination, which may save preparation time. You can read the post "What Color Garage Door With A White House?" for inspiration to select an ideal color.
2. Remove Hardware
You will be able to remove an entry door from its hinges, which will make the painting process much easier. Make sure the door is closed before you begin. You can simply use a hammer and nail.
You should only tap gently, and be careful of damaging the door or nearby molding. As soon as the hinge pins are loose enough, manually pull them out with your hand.
This may prove too difficult with hinge pins that are old and stuck. But you can still use a hammer with a commercially sold hinge pin remover, which will help protect the door and make it easier to remove stubborn pins.
Once you can position the door on its side, you will be able to use a power drill in order to remove all of the screws from the hinges, locks, and knobs.
If you are working with a garage door, the only hardware you will have to work around is the automatic door opener. You should unplug this feature and use the safety release so that you can manually move the garage door.
Metal doors may accumulate grease, oil, dirt, and rust. This is especially common for garage doors, where vehicles likely pass through on a daily basis.
But surface debris will create issues for the new paint. The surface will need to be completely cleaned and smooth, or else the primer and paint will not bond well.
How do you clean aluminum before painting it?
You will likely require a commercially sold multi-purpose cleaner, which will save you time and effort. Also, any lingering rust and chipped paint will need to be scraped off using a wire brush.
Next, the aluminum door should be washed and dried. If you need to clean an entire garage door, you can simply use a garden hose. It is often advised to avoid using pressure washers, which are too strong and may dent an aluminum door.
4. Sand and Clean
It is ideal to sand a metal door before painting it. Sanding the surface will increase the adhesion of the primer and paint. However, you will need to use the correct sandpaper grit. The grit is a measurement of how coarse the sandpaper is, with a higher grit being finer and a lower grit being rougher.
Experts such as Sandpaper America have advised that using the wrong kind of sandpaper can cause “irreversible scratch marks.” They recommend using a sandpaper grit of 320 or higher on metal.
Many others suggest using sandpaper as fine as 400 grit on aluminum doors. If the surface is stubborn, you may start with coarse grit and work your way up to a finer grit.
You can purchase a sanding block for larger surfaces, such as a metal garage door. Sanding blocks are sometimes sold with a built-in handle, which will make it easier to cover wide areas. You should consider wearing goggles, gloves and a mask to protect yourself from the resulting metal residue.
These leftovers will need to be cleaned up after you’re finished sanding. You can use a shop vacuum, which has a special tank and hose. It is designed for heavy-duty work, which means it will withstand tougher and larger debris.
5. Tape and Prime
Next, you may need to use painter’s tape in order to cover up areas you do not want to be primed or painted. That will usually include trim or molding.
This is very common when you need to work around garage doors, which cannot be separated from important areas like the keypad opener. Covering nearby surfaces may also be crucial if you plan on using spray paint, which has less control than a brush.
What's the best kind of primer for aluminum doors?
Even if you are using two-in-one paint, it is often best to add your own layer of primer anyway. This will only improve the aluminum surface and adhesion.
You should use a special self-etching primer, which includes a corrosive agent that will etch the bare metal and prime it in just one step. Etching the metal will increase the bond between the surface and paint.
Also, self-etching primers will usually add more rust resistance and create a smoother surface. They are often available in spray cans, which will be much easier to apply for broader surfaces like garage doors.
Paintbrushes are not considered best for aluminum doors, because they leave unsightly streaks. Usually, paint brushes are only used to reach inside panel grooves. Even then, these areas are often smoothed out with a paint roller.
Lightly apply the paint across your door with a paint roller, using long strokes. Wait for the first coat to dry, and then add a second layer. This will create a smoother, richer look. The drying time between coats will always vary, depending on the brand of paint and even the weather.
For garage doors, you should paint from the top down. This way, you can gradually slide the door upwards after each panel is completed. That will be necessary to keep the paint from dripping onto the lower panels while you continue working.
Afterward, you may require a utility knife to dislodge paint debris. This residue will likely build up between the panels, as well as between the panels and any rubber strips. If the residue isn’t removed, then it will set and you will have issues opening the garage door. You may need to sand it down the following day.
Can you use spray paint on aluminum?
As long as the aluminum surface is prepared correctly, it will successfully bond with spray paint. Spray paint will be easier to distribute, and it won’t require any rollers or brushes. Also, even though it will usually require more coats, it can dry more quickly than ordinary paint. You may also consider spray paint because brushes will leave frustrating streak marks that must be resolved.
However, consider that spray paint is usually oil-based and you are more likely to ingest the fumes. Oil-based paints contain VOCs or volatile organic compounds.
The United States Environmental Protection Agency has warned that VOCs might cause severe health issues ranging from liver damage to cancer. As such, make sure you are wearing a protective mask when applying spray paint. You should only use spray paint outside or in a very well-ventilated area.
Why does paint peel off aluminum?
There are multiple reasons that paint might be peeling from your aluminum. The main cause is usually rust, which corrodes the metal itself and causes any paint on the surface to chip. This is common with any exterior metal, such as aluminum siding, which is often subjected to harsh weather. You can read the post "How To Paint Aluminum Siding [5 Steps]" for details.
However, it may also be due to an improper application. This will usually involve mismatched products, or a failure to apply them correctly. Manufacturers will often provide instructions that are unique to their own products. These details should always be carefully followed.
Although it can take a lot of time and effort to paint an aluminum door, the steps are easy to follow and no tricky equipment is required. It is most important to understand the correct process, and which tools to use.
Metal doors require a unique sanding grit, special primers and rust protection. Now that it’s clear which products are ideal for metal, you can safely and effectively paint any aluminum door.