Most older garage doors are made of wood, however today's new garage doors are made of steel. They also have better insulation and are more secure. For rust protection, look for a door that has primer and/or polyvester topcoat.
If you are re-painting a steel door make sure you use latex paint which is water based and not void your warranty since it will not peel. Using an oil based paint will actually peel overtime due to the sun and that will cause your warranty to be voided.
Call Santa Clarita Gates and Doors to help you select and install your new garage door.
888-543-4450