How to Clean Aluminum Siding


Aluminum siding is a wonderful investment to beautify your home. It requires very little maintenance to keep it looking great. As with any part of your house, it will need to be cleaned about once a year to remove dirt and debris and keep it looking fantastic.

Pre-Cleaning Steps

Because you will be spraying water and cleaner all around your house, there are a few things to do to protect yourself and items around your house.

  • Close all windows and doors.
  • Turn off power to any outside electrical units such as lights, outlets, etc.
  • Cover plants such as shrubs or flowers to prevent the detergent from damaging them.
  • Cover any etched glass or metal that may be damaged by cleaning solutions.
  • Remove any other articles that may be in the way such as outdoor furniture or toys.
  • Check over the siding for signs of mold or mildew. If you’re unsure if it’s mold, place a drop of bleach on it. If it turns white, it’s mold; if it stays dark, it’s dirt.

Cleaning Aluminum Siding

You Will Need:

  • Laundry detergent
  • Water
  • Soft bristled brush and/or
  • Broom and old towels and/or
  • Sponge mop
  • Large buckets (5 gallon buckets work best)
  • Hose
  • Pressure washer (optional)

The Cleaning Process:

  1. It will be easiest to work around your house in 3-5 foot sections.
  2. Fill a large bucket with 4 gallons of water and mix in ¼ cup of laundry detergent.
  3. Gather your cleaning tool, either a brush, mop or wrap an old towel around the head of a broom and secure with duct tape. You’ll want something with a long handle.
  4. Begin by using the hose to spray away any loose dirt and debris. If you have a pressure washer available, that can be used in place of the hose and will likely lessen the amount of scrubbing needed. Be sure to use a low-pressure setting so it doesn’t dent the siding.
  5. Starting at the top, dip the chosen cleaning tool into the soapy water and begin scrubbing away any dirt and debris from the siding.
  6. Continue working your way down to the bottom of your section.
  7. Use the hose to rinse away the soapy water. Be sure to remove all the soap before it dries or it will leave a mark on the siding.
  8. Continue on, repeating steps 4-7 for each section.

Additional Tips and Advice

  • If you’re concerned about putting chemicals into the ground, there are several eco-friendly detergents available to choose from as well.
  • Trisodium Phosphate can also be used in place of the laundry detergent.
  • Bleach can be used to remove mildew build-up present on many houses. Mix a mild solution of 1 part bleach with 5 parts water and remove with a scrub brush.
  • If using a ladder to clean siding near the top of your house, have an additional person available to help. Trying to scrub with a mop or broom while standing on a ladder can be extremely dangerous and should be done with extreme caution.
  • A white build-up called chalk often appears on aluminum siding due to weathering. If this has occurred on your siding, it can be removed with a siding wash available at most home improvement or hardware stores and plenty of elbow grease.
  • If your house is too big to complete yourself, you may want to have a professional clean the siding.


  1. Wm and Paula says:

    We have a wood burning furnace. Smoke has seeped out into the soffits and fascia. Can you suggest how we remove the black soot marks? Same instructions as on dirty aluminum? Detergent and a power washer on low?

  2. Start from the top? I had been advised by an installer of aluminum siding, that you should always start at the bottom and work your way up. Which is correct? Top to bottom, or bottom to top?

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