Michigan Building Science Blog by WeatherGard

How to Clean Vinyl Siding


Cleaning your vinyl siding can give your home a fresh look. It’s also an easy project to do yourself to make your siding look like new without investing much time.

Vinyl siding is very durable and it looks great on almost any home, but it does require some cleaing every so often, especially for those with homes in areas more susceptible to airborne algae and mold.*} Fortunately, vinyl siding is designed to be cleaned, and can usually be made to look brand new without much effort.

Before and after cleaning image.
Left: before cleaning, siding is covered in mold growth and the dirty and debris that it attracts. Right: the vinyl has been washed clean, appearing virtually new again.


There are a few important things you will want to have done before getting started with the garden hose:

  1. Make sure all your windows and doors are closed, to prevent dirty water from ending up inside.
  2. Cover any plants or shrubs that could be damaged by the detergent.
  3. Turn off the power to any exterior light fixtures and/or power outlets and cover electrical fixtures with plastic bags to prevent water from causing them to short when the power is restored.

Cleaning the Siding

Now that you’re prepped here’s what you’ll need:

  1. Ordinary laundry detergent (any brand is fine), to loosen dirt, mold, and mildew.
  2. A soft-bristled brush for scrubbing heavily soiled areas.
  3. A sponge mop (or alternatively, you can use an broom wrapped in old towels assuming that you don’t mind getting yourself pretty dirty)
  4. A mop bucket in which to keep your soapy water.
  5. Your garden hose, for rinsing the siding after scrubbing.

To begin, spray the house with the hose to remove the loose debris. Fill your bucket with 4 gallons of water and mix in ¼ cup of laundry detergent. Use your sponge mop and start from the bottom working your way up. If you come across a stubborn stain use the soft bristled brush. Working in a side to side motion will give you the best results. Once you’re done scrubbing, rinse as soon as possible, starting from the top and working your way down to prevent streaking.

You can also use a power washer with a 25-degree nozzle that won’t damage the siding. When using the power washer, avoid spraying directly onto the seams; you don’t want to force water behind the vinyl panels. Start at the bottom and work your way up when using soap and start at the top and work your way down when rinsing.

Additional Tips

Here are a few extra tips to help you with this project:

*For example, homes near large bodies of water may have dirtier siding.

This article was written by WeatherGard and was published in July 2012.