How to Clean Stained Vinyl Siding: A Step-by-Step Guide

Vinyl siding is an outdoor surface that is exposed to harsh elements, so it accumulates dirt, pollen, rust, spider webs, and bird or insect droppings over time. In damp areas, your siding may also grow mold, mildew, or even algae.

Luckily, this durable surface is also pretty easy to clean. All you need are some basic items and a few household cleaners, plus some good weather. Then, it’s just a matter of elbow grease and a couple of hours to get rid of stains on your vinyl siding. The result is a home exterior that looks practically new and has serious curb appeal!

Before You Begin

• Avoid windy days. Cleaning vinyl siding when it’s windy can cause the cleaning solution to spread and damage nearby plants or surfaces.

• Do not use metal scrapers or steel wool on vinyl siding stains. Vinyl is a soft material which metal will scratch and damage.

• Watch out for wasps. If you find signs of wasps under your eaves or on your siding, you should have them removed before you begin.  

Equipment and Materials Needed

• Long-handled broom
• Mop or cleaning rags
• Garden hose
• Oxygen bleach
• Plain water
• Stain removers (see steps below)

Steps to Clean Stained Vinyl Siding

Step 1: Sweep.

Start by using the long-handled broom to sweep debris off of your home’s vinyl siding. Pay attention to areas where insects and spiders like to nest. Some areas to look include: under eaves and bay windows, beneath raised decks, and around windowsills. You may want to wear long-sleeves and pants for this.

Step 2: Make a vinyl siding cleaner.

In a bucket, combine 1 gallon of water and 1 cup of oxygen bleach. (Oxiclean is one brand, or you can make your own oxygen bleach.) This mixture will remove soot, dirt, pollen, light mold, and mildew from your vinyl siding. But, unlike chlorine bleach, the oxygenated kind won’t harm plants or landscaping. Fill the second bucket with plain water for rinsing.

Step 3: Wash and scrub your siding.

To clean your vinyl siding, dip a rag or mop into the cleaning solution and work from top to bottom, scrubbing side to side. Work in 6-foot areas so the cleaning solution does not dry out. For hard-to-reach spots, use a broom or a mop dedicated for this purpose. Rinse the rag or mop in the plain water before dipping it into the cleaning solution to keep the mixture fresh. Replace the cleaning solution and rinse water when they look grimy.

Step 4: Rinse away the solution.

After washing an area, turn the hose on full blast and rinse it. You don’t want to let the cleaning solution dry on your vinyl siding, so work in 6-foot spots, rinsing each after cleaning.

Step 5: Remove stains. 

Rust stains: To remove rust stains from vinyl siding, mix baking soda and water into a paste and apply it to the affected area with a cloth or soft-bristled brush. Alternatively, use a commercial product like Bar Keeper’s Friend or Soft Scrub. Avoid using steel wool, which can scratch and damage the vinyl.

Sticky spots: Apply a small amount of olive oil to a cleaning rag or use Castile soap or Murphy’s Oil Soap. Let it sit for several minutes to loosen the grime, then use an old credit card or rubber spatula to scrape away the mess. Finally, wash and rinse the area thoroughly.

Paint: To remove paint stains from vinyl siding, dampen a white cloth with rubbing alcohol or a product like Krud Kutter and press it onto the stain. Allow the paint to soften before using the edge of a credit card or rubber spatula to lift the spot. Finally, wash and rinse the area thoroughly.

Algae: Create a solution by mixing one part white vinegar with three parts water in a bucket. Apply the solution to the affected area and let it sit for 10-15 minutes to penetrate the growth and break it down. Scrub the area with a rag and rinse it well.

Mold or mildew: To remove mold or mildew stains from vinyl siding, create a cleaning solution by mixing 2 tablespoons of borax, 2 ounces of white vinegar, and 16 ounces of hot water in a spray bottle. Spray the affected area and let the solution sit for 15 minutes to penetrate the stain. Scrub the area with a clean, damp cloth and rinse it thoroughly.

Step 6: Prevent further stains.

To prevent stains on vinyl siding, trim trees and shrubs away from the siding to avoid sap and pollen stains. Clean gutters twice a year to prevent clogs and water damage that can lead to mold. Regularly inspect siding for gaps, cracks, and holes, and promptly repair them to prevent water damage and structural issues.

Additional Tips

• Avoid using a power washer on vinyl siding. Improper pressure washing can ruin the material and lead to water and mold building up in your home’s walls. If you choose to use a pressure washer, follow all manufacturer’s instructions and keep the PSI between 1,200 and 1,600. Start with the lowest pressure and gradually increase it as needed.

• Clean your vinyl siding at least once a year. If your area is prone to mildew or has high pollution, do it as part of Spring Cleaning and again before winter to keep stains from becoming permanent.