How to Remove Rust Stains From Concrete With a Pressure Washer?

Mar 1, 2025

Rust stains on concrete can be an eyesore and diminish the look of your driveway, patio, or other concrete surfaces. Can I pressure wash rust off concrete? Yes! Thankfully, a pressure washer is an effective tool for removing these stubborn stains and restoring the look of your concrete.

So, how to remove rust stains from concrete with pressure washer? To remove tough rust stains from concrete using a pressure washer, apply a rust removal chemical, let it sit for 30-60 minutes, scrub with a stiff brush, and then rinse thoroughly with the pressure washer using an oscillating fan spray pattern while keeping the nozzle 6 inches above the surface.

In this guide, we’ll walk through 6 methods for using a pressure washer to erase those pesky rust marks. So grab your pressure washer, and let’s get started!

Safety First

Before we dive in, it’s important to take some safety precautions when using a pressure washer:

  • Wear protective eyewear and closed-toe shoes – the high-powered spray can damage eyes and skin.
  • Make sure there are no people, pets, or delicate objects nearby that could be harmed by the pressurized water.
  • Check that all house pressure washing parts are in working order before turning it on.
  • Never point the wand at yourself or others.

Okay, now that safety is covered, let’s rustle up these stains! (Get it? Rustle? Rust? Okay, moving on).

How to Remove Rust Stains From Concrete With Pressure Washer? Method 1: Baking Soda and Vinegar

For light rust stains, try creating a simple cleaning solution:

  1. Sprinkle baking soda liberally over the stained area.
  2. Spray or pour vinegar over the baking soda – you’ll see it start to bubble and fizz.
  3. Let sit for 2-3 minutes.
  4. Blast away with your pressure washer!

The chemical reaction between the baking soda and vinegar helps break down the rust stain. Can a pressure washer remove rust? Absolutely.

Method 2: Lemon Juice and Salt

For mild to medium rust stains, harness the natural acidity of lemon juice:

  1. Squeeze lemon juice onto the stained area and sprinkle with salt.
  2. Let sit for 5 minutes.
  3. Scrub with a stiff bristle brush.
  4. Rinse with your pressure washer.

The acidity in the lemon juice helps dissolve rust, while the salt provides an abrasive action.

Method 3: Oxalic Acid Cleaner

For tougher rust spots, use an oxalic acid-based cleaner:

  1. Wear rubber gloves and eye protection.
  2. Apply an oxalic acid cleaner to the stain.
  3. Let sit for 10-15 minutes.
  4. Rinse thoroughly with your pressure washer.

Oxalic acid dissolves rust and leaves the concrete looking clean. Just be sure to rinse it all off thoroughly!

Method 4: Power Washer and Degreaser

For large rust stains:

  1. Cover the stained area with a quality concrete degreaser.
  2. Let sit for 5-10 minutes.
  3. Blast away with your pressure washer!

The degreaser helps break down the rust stain while the mechanical action of the pressure washer removes it.

Some Things to Consider When Pressure Washing Concrete

When using a pressure washer, it’s important to be careful not to use too high of PSI (pounds per square inch) on concrete surfaces, as this can actually damage or crack the concrete. Most standard concrete can withstand between 1500-3000 PSI before risking harm. Homeowners should aim to use pressure washers with less than 2000 PSI and use a fan spray nozzle instead of a tight zero-degree nozzle. Keep the nozzle about 6 inches away, and avoid holding it in one place too long. Also, check for any existing cracks or vulnerabilities in the concrete before pressure washing. With some simple precautions, you can use a pressure washer to clean concrete without damaging the surface.

Method 5: Wet Sandpaper

For really stubborn stains:

  1. Wet 300-400 grit sandpaper and sand the rusted area.
  2. Rinse thoroughly with your pressure washer to remove all debris.

The light abrasion helps remove the stain, while the water prevents dust.

Method 6: Rust Remover Spray

  1. Spray rust remover chemicals onto the concrete.
  2. Let sit for 30-60 minutes.
  3. Scrub with a stiff brush.
  4. Rinse thoroughly with your pressure washer.

Look for rust removers with oxalic or phosphoric acid designed for concrete. It does the hard work of breaking down the rust so the pressure washer can whisk it away.

When to Call a Professional

If you have large or deep set rust stains, or if they cover a big area, you may need to call in a professional pressure washer service. Professionals have industrial-grade equipment and specialized chemicals to remove stubborn rust stains and restore your concrete.