How to Clean Aluminum Siding for a Like-New Exterior

Occasionally cleaning aluminum siding keeps maintenance to a minimum

An one-story house with aluminum siding and a frontyard
Photo: pamspix / iStock / Getty Images Plus / Getty Images
An one-story house with aluminum siding and a frontyard
Photo: pamspix / iStock / Getty Images Plus / Getty Images
Kelly Weimert
Written by Kelly Weimert
Contributing Writer
Updated February 27, 2024
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If you’ve ever installed new siding on your home, you know the satisfying feeling of refreshing the home’s design with a new look. If you install aluminum siding, you receive a long-lasting material that requires a minimum amount of maintenance. Even better, to maintain that feeling of a like-new exterior, all you need to do is learn how to clean aluminum siding. Dirty siding can take the luster off your home in a hurry, but simply cleaning it once a year gives you significant benefits for a small amount of work.

Why You Should Clean Your Siding Regularly

Over time, aluminum siding may end up with dust, grime, and mold on it. That grime can consist of insecticides, spray fertilizer, pollen, sticky tree sap, and any other outside debris surrounding your home. It’s important to clean your siding at least once per year to keep mold and mildew from appearing. If you live in an area where wildfires happen, you may end up with soot and ash clinging to the siding and need to clean it even more frequently.

Leaving these contaminants on the aluminum causes it to look dingy and old before its time. Contaminants can speed up the oxidation process on aluminum siding, too, which forces you to have to paint the material sooner. 

When you end up needing to paint older aluminum siding, you must clean it ahead of time to ensure the best painting results.

How Much Does It Cost to Clean Aluminum Siding?

Compared to the aluminum siding cost for installation, which averages almost $12,000, the cost for cleaning aluminum siding is minimal. 

Pressure washing is the most common method for how to clean aluminum siding. The average cost to pressure wash a house from a pro is about $300. The pro may need a bit more time and a cleaning solution to pressure wash the aluminum siding, so you could pay $300 to $600 for a pro to do the work, similar to the cost of cleaning vinyl siding.

If you’ll do the work yourself, you can purchase or rent a power washer. You also may need a soft-bristle scrub brush with a long handle, cleaning solution, a hose, and a ladder. If you need to buy all these things, you can expect to pay around $700. If you only need to purchase the scrub brush and the cleaning solution, the cost is around $50.

You will get wet from splashes and spray while doing this job, so you may want rubber gloves, safety goggles, and rain gear.

How to Prep for Cleaning Aluminum Siding

A man covering the windows with plastic wrap
Photo: FotoDuets / iStock / Getty Images Plus / Getty Images

It typically works best to do one side of the house at a time. You can fully clean and rinse the aluminum siding on one side before restarting the process on the next side. If you try to clean the entire house and then rinse the entire house, some of the residue from cleaning almost certainly will remain on the siding.

Before cleaning the siding, move any exterior furniture or your barbecue grill out of the way. You may want to cover any plants near the home’s foundation with plastic. This can protect them from excessive water and from the cleaning solution. You only need enough plastic for one side of the house by doing one side at a time. Additionally, you should use plastic and tape to cover:

  • Light fixtures

  • Electrical outlets

  • Leaky windows

  • Air conditioning unit

  • Fire pit

If you don’t want to move the ladder back and forth, you can work on a section of one side of the house before moving to the next section. Working on a section about 10 to 15 feet wide should make the process easy. You also could set up two or three ladders to make doing an entire side of the house go faster.

How to Clean Aluminum Siding

A person power washing his house
Photo: ungvar / Adobe Stock

1. Wet the Siding

Before starting the cleaning process, use a garden hose and spray nozzle to wet down the aluminum siding. Always start at the top of the house and move downward, as this rinses any particles down to the ground.

You may notice some of the particles, like dust, rinsing away during this step, but it probably will not completely clean the siding.

2. Pressure Wash the Siding

Add the cleaning solution to the pressure washer’s detergent tank. Use a low or medium setting on the pressure washer with an angled tip on the nozzle. 

Spray the nozzle at a downward angle, holding it 18 to 24 inches away from the siding at all times. Work down from the top of the house to the foundation. This moves the grime and cleaning solution downward while also preventing water from going up and under the siding.

3. Scrub the Siding

Now it’s time to scrub the aluminum siding by hand. Look for spots where any grime, mildew, or mold remains in place after pressure washing. Use the soft-bristle siding scrub brush to loosen or remove stubborn stains. 

If the siding looks clean after pressure washing, you can skip this step.

4. Rinse the Siding

Remove or empty the detergent tank from the pressure washer and climb to the top of the house again. Now use the power washer to rinse the cleaning solution and any remaining particles with water only. 

Again, use an angled tip and hold the nozzle 18 to 24 inches from the siding.

How to Clean Aluminum Siding Without a Pressure Washer

If you don’t own a pressure washer or don’t feel comfortable using one, you can learn how to clean aluminum siding by hand. 

Just pre-wet the siding with the hose and sprayer, as described in step one. Then use a lawn and garden sprayer bottle to apply the cleaning solution to the siding. Scrub it with the brush. Because you are not using the pressure washer, you will want to scrub the entire section of siding rather than only spots that are showing grime.

Then rinse it with the garden hose again. As with the pressure washer, always work from the top of the house downward.

Safety Tips for Cleaning Aluminum Siding

Because you will be climbing a ladder in wet conditions and using detergent, the process of cleaning aluminum siding requires some care to keep yourself safe.

  • Use shoes with a non-slip sole.

  • Wear goggles to protect your eyes.

  • Go up and down the ladder slowly to reduce the chance of slipping.

  • Don’t reach too far with the brush while on the ladder, risking losing your balance.

  • Watch for any overhead wires.

  • When working in a sunny area, remember that the aluminum siding could be extremely hot to the touch.

  • If any siding is loose, the edges could be sharp, so wear thick safety gloves.

DIY vs. Hiring a Pro

Cleaning your aluminum siding yourself is going to be a messy, wet job. It’s going to require you to go up and down the ladder dozens of times, which can be tiring. You also may have to work 20 feet or more off the ground if you have a multi-story home.

If you don’t feel comfortable climbing a ladder repeatedly, especially when the ladder and your shoes are wet, this might be a job best left to the pros. Additionally, if you don’t own a pressure washer, this job will take far longer. Hiring a local siding contractor takes care of this problem, as the pro will have all the ladders and other equipment needed to do the work efficiently.

Frequently Asked Questions

No matter what types of metal siding you are cleaning, you should be able to clean them using the same processes you use for aluminum siding. Steel siding and aluminum siding both need cleaning about once per year. You can clean metal siding or aluminum siding without a pressure washer or with one.

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Learn more about our contributor
Kelly Weimert
Written by Kelly Weimert
Contributing Writer
Kelly has been a professional writer and editor in the home and interior design space for over ten years.
Kelly has been a professional writer and editor in the home and interior design space for over ten years.
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