How To Clean Metal Siding Before Painting

Using too much pressure can dent your steel siding or damage the paint.

How to clean metal siding before painting. You don t need to get down to bare shiny metal just clean off the flakes and powdery surface rust that prevent paint from adhering. As long as the siding is clean you won t need to use a primer unless raw metal is exposed. Put those away and simply make up a solution of 1 3 cup liquid laundry detergent and 6 gallons of water to use with the pressure washer. Then rinse off the siding again with clean water.

When a panel section is clean rinse the washed panels with fresh water. It will definitely remove the dirt but the paint as well. Or you could wash it by hand with tsp or a similar product available at home centers and paint stores and rinse it thoroughly. Rinse frequently with clear water and allow the surface to dry before painting.

Beginning at the bottom portion of a panel section wipe in a left to right motion until clean. If a panel becomes difficult to clean continue rubbing longer but do not increase pressure. When washing metal siding it s best to get the nozzle as close to the siding as possible which makes the most use of the powerful water stream. Sheets of chalky water streamed off the house like dirty milk.

Add liquid soap to the water to get the grime off. Choose one side of the house as your cleaning project of the day and stick with it. Allow it to dry for two or more days before continuing. However badly rusted metal areas need more prep work and possibly a special primer.

I worked my way down the ladder blasting away the detergent and chalk cleaning one wall at a time. Chemicals you might use on wood or vinyl siding can cause damage to steel. For aluminum siding use a pressure washer set on low to spray the metal siding and rinse the rust off. Soak a heavy cloth or sponge with glasswax.

Use your pressure washer to get to all the cracks and crevices you could not reach with the brush. Set power washer to the lowest setting available. The first step is to clean off loose rust and flaking paint and then apply a rust inhibitive primer. With the siding dry remove large pieces of debris with the wire brush broom and even a shop vacuum.

Make sure to use the power washer on the lowest setting it has. Efflorescence mold and algae lichen and stains from chalking paint or rusting metal are problems that you should attend to before painting masonry which includes surfaces such as stucco brick and concrete block. Check the label to be sure it s recommended for metal siding. The best way to get this siding clean is to power wash it.

Expect to pay the premium for good paint.