If you have aluminum storm doors you may be concerned that exposure to the elements will lead to rusting.
In fact, however, aluminum doors don’t rust – it’s one of the primary reasons it is used as the metal of choice for storm doors. When aluminum oxidizes, it forms a white powder. However, if you have steel screws or fixtures on an aluminum door, or you have a door of another type of metal as well as aluminum, you may have some rust.
Keep it Clean
The best way to prevent rust on the fixtures or screws is to keep the door free of dirt and debris. A thorough cleaning at least twice a year where you wash the door off well and wipe it down with a soft cloth should do wonders for keeping rust away.
Seal the Fixtures
Use a thin coat of petroleum jelly on the fixtures and handles to provide a coating to protect from rust. You may also use car wax or clear nail polish as a protectant.
On other metals, sanding to remove rust is recommended. However, because oxidated aluminum does not "rust" (only look dull, powdery and grey) sanding is unnecessary. Its this property of aluminum that makes it so useful for exterior uses.