The first step includes cleaning.
Painting steel house siding.
Start at the top of the wall and across the length of the metal siding.
Paint the steel siding panels using the sprayer.
Wash the steel siding with trisodium phosphate tsp and use a pressure washer to rinse thoroughly.
It also helps to peel away the previous paint on the steel siding leaving it neat and clean.
Since any of this is clearly bad for your metal siding it is vital that you re paint your metal siding.
Cleaning of the surface can be done by hand washing with warm soapy water or with the use of a high pressure washer 2500 psi minimum.
For steel use a latex bonding primer instead of a regular metal paint primer.
Trigger the sprayer to begin the paint flow and use a back and forth motion to cover the length of the panel with an even coat of paint.
Step 1 clean the steel siding.
This is followed by fading and thinning of the color.
The first sign that this is beginning to happen is a loss of the glossy look that new siding has.
This will help clean away all the dirt that accumulates on the steel siding.
Aim the sprayer nozzle directly at the panels eight inches from the siding surface.
As with all exterior painting projects proper surface preparation is the key to restoring your metal siding.
But i would use the oil based rust oleum primer which by the way takes forever to dry.
Do this as soon as any spots start to show the steel underneath or do it a little sooner if you are trying to sell your house.
Begin by thoroughly cleaning your siding of all loose dirt chalk and other contaminants.
Then apply the primer to the metal siding in even strokes.
Depends on the weather but three or four or five hours is not unusual.
And then i would use the rust oleum top coat.