How do I clean vinyl siding, especially areas that have mildew or mold?

– Elvin

Even though vinyl siding is a low maintenance material, it still needs cleaning from time to time to remove dirt and grime. In humid climates vinyl siding may also develop mold or mildew, which should be removed as well.

Cleaning instructions are usually available from the vinyl siding manufacturer, and are often found on the siding warranty. If instructions are not available, or you’re not sure what brand of siding you have, follow the procedure below to clean your vinyl siding.

Removing Dirt from Vinyl Siding

Hosing down vinyl siding with a garden hose equipped with a spray nozzle or a pressure washer set on a medium spray pattern is often enough to remove dirt and grime. When hosing down or pressure washing vinyl siding:

  • Make sure the pressure washer spray pattern is wide enough to prevent damage to the siding, and keep the nozzle moving.
  • Start washing at the bottom and work your way up; then rinse from the top, working your way down.
  • To prevent water from running behind the siding, spray even with or down on the siding, and spray in the direction of the overlapped joints.

Cleaning Solution for Vinyl Siding

If the vinyl siding needs additional cleaning, add special cleaning solution to a pressure washer, or mix up the following in a bucket to use to clean by hand:

  • 1 gallon water
  • 1/3 cup powered laundry detergent
  • 2/3 cup TSP (trisodium phosphate) cleaner

Dip a long handled, soft bristle, car cleaning brush in the solution; and scrub the vinyl siding gently starting at the bottom and working your way up. Follow by rinsing off the cleaning solution with a garden hose, starting at the top and working your way down.

Removing Mold and Mildew from Vinyl Siding

To kill mold and mildew on vinyl siding, apply a mold and mildew remover, such as Wet & Forget Outdoor.

You can also use bleach to treat mold and mildew on vinyl siding by adding one quart of household bleach to each gallon of the cleaning solution above, then:

  1. Wet down any plants near the house, and/or cover them with plastic sheeting to prevent damage from bleach. Covering plants with plastic on a sunny day may cause damage from overheating, so remove the plastic as soon as possible.
  1. Use a pump up sprayer to wet the siding down with the diluted bleach/cleaning solution, working from bottom to top.
  1. Allow the bleach solution to remain on the siding for 10 minutes or so.
  1. Scrub the siding from bottom to top with a long handled, soft bristle brush.
  1. Rinse the bleach solution off the siding from top to bottom with a garden hose.

CAUTION: Wear rubber gloves, long sleeve shirt, long pants, and goggles when working with strong chemical cleaners such as TSP and bleach. Follow the instructions on cleaning products carefully. Do not mix bleach with cleaners that contain ammonia, vinegar, or any cleaner that says it should not be mixed with bleach, since it can cause a chemical reaction and release poisonous chlorine gas.

Good luck with your project,


Further Information

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Danny Lipford

Founder

Danny Lipford is a home improvement expert and television personality who started his remodeling business, Lipford Construction, at the age of 21 in Mobile, Alabama. He gained national recognition as the host of the nationally syndicated television show, Today's Homeowner with Danny Lipford, which started as a small cable show in Mobile. Danny's expertise in home improvement has also led him to be a contributor to popular magazines and websites and the go-to source for advice on everything related to the home. He has made over 200 national television appearances and served as the home improvement expert for CBS's The Early Show and The Weather Channel for over a decade. Danny is also the founder of 3 Echoes Content Studio, TodaysHomeowner.com, and Checking In With Chelsea, a décor and lifestyle blog.

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