7 Simple Steps to Clean Stucco Siding Without Damaging Your Home

To maintain that unique look, you’ll need to use a gentle touch

Ben Kissam
Written by Ben Kissam
Updated May 11, 2022
White stucco house with arches
Photo: Stephen Coburn / Adobe Stock
Difficulty

Simple

Flex your DIY muscles.

Time to complete

3 hours

1 to 3 hours (split into two days if using sealant)

What you'll need:

TOOLS

  • Pressure washer
  • Caulking gun
  • Bristle brush

SUPPLIES

  • Cleaning Solution (pick one):
  • Concentrated cleaning solution (stucco siding approved)
  • Bleach and water
  • Borax, dish soap, and water
  • Sealant

Many homeowners opt for stucco exterior over other types of house siding thanks to its unique appearance and fantastic durability. It’s also pretty easy to clean and maintain, as long as you know what you’re doing when tackling a DIY stucco repair project.

But you should avoid damaging your stucco siding when you clean it — as stucco repairs cost as much as $1,400.

Learn how to clean stucco siding safely and efficiently, as well as how to preserve your investment in stucco siding, in this seven-step guide.

  1. Look for Cracks, Gaps, and Other Signs of Damage

    Stucco siding combines Portland cement, lime, sand, and water. This mixture adds a sleek design while helping to insulate your home. This goes for traditional stucco siding, at least. Newer synthetic designs, which are more expensive, use acrylic resin instead of cement. Stucco siding installation costs between $750 and $19,000.

    However, one of the problems with stucco is that weather can damage it, causing small gaps and cracks that you’ll want to address before cleaning. Otherwise, you risk inviting mold and mildew, or even water, into the cracks.

  2. Mend or Seal Any Damage

    Man holding a caulk gun is sealing wall crack
    Photo: Brett / Adobe Stock

    Carefully apply sealant to cracks and areas that may need reinforcement (i.e. visible signs of wear and tear, or just general deterioration). Some products come with a nozzle where you can easily apply it from the gallon bucket, while others may require you to load the sealant into a caulking gun yourself.

    A gallon of clear, water-resistant stucco sealants costs about $20 at home improvement stores and can fill any imperfections in your home’s siding. The best sealant material is a no-odor silicon-based product.

    Keep in mind, sealant takes anywhere from 10 to 24 hours to completely dry. Carefully read the manufacturer’s recommendation on drying times before using a power washer on your home. 

  3. Understand Why Stucco Siding Needs a Special Cleaning Approach

    Closeup of a stucco house wall
    Photo: OliverChilds / E+ / Getty Images

    Cleaning a home with vinyl or wood siding is often as easy as cranking the pressure washer up and blasting away mold, mildew, dirt, and other buildup on your home’s sides.

    However, you’ll need to take a more cautious approach when cleaning stucco. Stucco materials (especially sand and lime) can be wiped away if you blast your siding at point blank range or on a high pressure setting, which will damage your siding instead of clean dirt off it.

    You can still use a pressure washer on stucco, but you’ll need to use a low setting from a safe distance of about seven to ten feet.

    If you’d rather not do the job yourself, the cost to hire a pro to pressure wash a house can be as little as $100. Ask a local pressure washing service for a quote on your home.

  4. Choose a Cleaning Solution

    Hand holding container with pressure washer cleaning solution
    Photo: Владимир Феофанов / Adobe Stock

    A few cleaning products can effectively wash away dirt and grime on your stucco siding. You’ll need to pick the one that’s right for you.

    The three most effective cleaning solutions for stucco siding are:

    • A store-bought concentrated cleaning solution (make sure you choose one that’s approved for stucco siding)

    • Bleach and water (equal parts)

    • Borax, dish soap, and water (2 gallons of water for every 1/2 cup of borax and 2 tbsp of dish soap)

    The borax/dish soap solution is the least harsh chemical of the three.

  5. Prepare Your Pressure Washer

    Load your cleaning solution into the pressure washer and power it on. Remember, you’ll need to use a low setting to clean your stucco.

    Before using your pressure washer, consider walking around with a soft bristle brush to remove dirt or grime by hand in areas you can reach by hand. This is a gentler way to get rid of any buildup.

  6. Spray Your Stucco Siding Downward

    Man using pressure washer to clean exterior wall
    Photo: ronstik / Adobe Stock

    For efficient cleaning, start from the top of your stucco and work your way down as you blast away grime and dirt. 

    Both the cleaning solution and grime coming off the wall will trickle downward (thanks, gravity!), so you can avoid having to go over the same areas two or three times by simply working your way from high to low.

  7. Give Surrounding Shrubs and Foliage a Splash of Clean Water

    Man in the backyard watering plants with hose
    Photo: olezzo / Adobe Stock

    This last step is optional, but a good idea if you used bleach or if several shrubs or trees surround your home.

    A rinse of regular water from the hose or power washer on a low setting will help dilute any chemicals, helping to preserve the health of your plants.