Cleaning Vinyl Siding

How do I wash vinyl siding?
Wash vinyl siding with a soft cloth or ordinary long-handled, soft bristle brush. For textured surfaces, use only a soft bristle brush to keep the grooves in the texture stain-free. For best results, start at the bottom of the house and work up and rinse the cleaning solution completely before it dries. If your house has brick facing, cover the brick so that it is not affected by the runoff.

Can I use a power washer?
Yes, though you should read the washer instructions carefully before use. When cleaning, hold the power washer straight at eye level to keep the water on top of the vinyl siding where it can clean most effectively. Do not aim the power washer upward as water may be driven behind the siding.

You should also follow the siding manufacturer’s recommendations. Some manufacturers don't want pressure washers used on their products at all. Others allow them, but have limitations on the amount of pressure and the cleaners that can be used. Most will caution against the use of pressure washers around any opening in the wall, such as windows, doors, electrical wiring, and plumbing.

How do I remove mold and mildew?
Small spots of mold and mildew can be handled with cleaners such as Fantastik® or Windex®. For larger sections, a solution of vinegar (30%) and water (70%) has proven successful. Alternatively, you also could try the following solution: 1/3 cup (2 2/3 ounces) powdered laundry detergent (e.g., Tide®, Fab®, or equivalent), 2/3 cup (5 1/3 ounces) powdered household cleaner (e.g., Spic & Span®, Soilax®, or equivalent), 1 quart (32 fluid ounces) liquid laundry bleach, and 1 gallon (128 fluid ounces) of water.

What types of cleaners should I use for other stains?
A list of commonly accepted cleaners is provided in the box below. Be sure to spot check any general or stain specific cleaner before using it on a large section of siding. After removing the stain, rinse thoroughly with water. Do not use cleaners containing organic solvents, undiluted chlorine bleach, liquid grease remover, nail polish remover, or furniture polish or cleaners. They can affect the surface of the siding.

Vinyl Siding Cleaners

General cleaners (e.g., Simple Green®, Nice & Easy®, Armor All®, etc.) can be used to clean dirt, bird droppings, and spider webs. Stain-specific cleaners are listed below. Rinse all cleaners with water before they dry.

Stain
Cleaners*

Bubble Gum
Fantastik®, Murphy Oil Soap®, solution of vinegar (30%), water (70%) and Windex®

Crayon
Lestoil®

DAP (oil-based caulk)
Fantastik®

Felt-tip Pen
Fantastik®, water-based cleaners

Grass
Fantastik®, Lysol®, Murphy Oil Soap®, Windex®

Lithium (car) Grease
Fantastik®, Lestoil®, Murphy Oil Soap®, Windex®

Motor Oil
Fantastik®, Lysol®, Murphy Oil Soap®, Windex®

Paint
Brillo® Pad, Soft Scrub®

Pencil
Soft Scrub®

Rust
Fantastik®, Murphy Oil Soap®, Windex®

Tar
Soft Scrub®

Top Soil
Fantastik®, Lestoil®, Murphy Oil Soap®

*Cleaning Materials are listed in alphabetical order.
*VSI does not endorse products or processes and makes no warranties for the products referenced herein. Reference to proprietary names is for illustrative purposes only and is not intended to imply that there are not equally effective alternatives.

Taken from http://www.vinylsiding.org/aboutsiding/cleanmain/cleaning/index.asp