Composite Deck Cleaning: What Homeowners Should Know

Why composite deck cleaning matters

Composite decking is popular because it resists rot and usually requires less maintenance than wood. That said, composite surfaces still collect dirt, pollen, algae, and stains that can make your deck look worn and become slippery. Regular cleaning preserves appearance, improves safety underfoot, and reduces the need for more aggressive repairs down the line.

How Code 3 approaches composite deck cleaning

As a firefighter-owned, fully insured exterior cleaning company serving Kenosha County, WI and Lake County, IL, Code 3 Cleaning focuses on methods that are effective without damaging decking materials. We use soft washing and low-pressure techniques where appropriate, combined with cleaning solutions and agitation that are safe for most composite surfaces. Our goal is to lift biological growth and remove surface soils while protecting the deck’s finish and the surrounding landscape.

Soft washing and low-pressure methods: what they mean

• Soft washing uses low-pressure water flow and cleaning agents to remove mold, mildew, and algae without subjecting the surface to high PSI that could force water into joints or damage the deck surface.
• Low-pressure rinsing finishes the job by removing residue and restoring the deck’s appearance without scouring or etching composite boards.

Common contaminants and how they’re treated

Composite decks can pick up a range of stains and deposits. Typical issues we address include:

• Mildew and algae: These grow in shaded, damp areas and make decks slippery. They respond well to low-pressure cleaning with appropriate cleaning agents followed by thorough rinsing.
• Dirt and pollen: Seasonal buildup can dull colors. Gentle agitation with a soft brush and low-pressure rinse usually restores appearance.
• Oil and food stains: Fresh spots are easier to remove; older grease may require targeted cleaning while avoiding harsh scrubbing that could scratch the surface.
• Rust or tannin stains: These are sometimes stubborn. We assess each stain and recommend the safest approach—often starting with manufacturer-approved techniques or trialing a small area first.

What homeowners should do before professional cleaning

Prepare your deck and property to get the best results from a professional visit:

• Remove furniture, planters, grill covers, and loose items from the deck surface.
• Sweep away loose debris and leaf litter so treatments can contact the board surface.
• Point out items like outdoor rugs, pet bowls, and attached planters that may need special care or removal.
• Tell the crew about any manufacturer care instructions, warranty considerations, or areas with previous repairs.

DIY: When to clean yourself vs. call a pro

Homeowners can perform regular maintenance such as sweeping, rinsing with a garden hose, and spot cleaning with a soft brush and mild cleaner that the deck manufacturer approves. However, consider hiring a professional if:

• The deck has widespread biological growth or stubborn stains.
• There are hard-to-reach areas, tall railings, or multi-level sections where safe access is a concern.
• You’re unsure which cleaning products or methods are compatible with your decking warranty or surface finish.

Professionals bring experience in selecting low-pressure techniques and in protecting nearby plants, structures, and finishes during the cleaning process.

Safety and landscape protection

Protecting surrounding landscaping, railings, and house trim is part of thorough composite deck cleaning. We normally pre-wet plants, rinse areas around the deck, and use targeted application methods that keep cleaning solutions on the deck surface. Because Code 3 is fully insured, you have added peace of mind while we work on your property.

Maintenance schedule recommendations

Frequency varies by local conditions—shaded decks and those near mature trees often need cleaning more often than decks with full sun exposure. A common approach is:

• Light maintenance (sweeping, spot rinsing) monthly during heavy-pollen seasons.
• Thorough cleaning once a year for most decks, more often if algae or mildew returns faster due to shade and moisture.

Follow any specific manufacturer recommendations for your decking product to avoid voiding warranties.

Local conditions we consider in Kenosha County and Lake County

In Pleasant Prairie and the surrounding communities, seasonal changes and humidity can promote biological growth on outdoor surfaces. During spring and late summer, pollen and algae are common. Code 3’s team is familiar with these patterns and selects appropriate timing and methods to get long-lasting results while minimizing disruption to your outdoor use.

FAQ

Is pressure washing safe for composite decks?

High-pressure washing can damage some composite surfaces or drive water into joints. We favor soft washing and low-pressure approaches where appropriate. If a situation requires a different technique, we evaluate the deck first and proceed cautiously.

Will cleaning change the color of my composite decking?

Proper cleaning restores the deck’s appearance by removing surface soils and biological growth; it should not remove factory pigments. Aggressive scrubbing or incorrect chemicals can affect the finish, which is why following manufacturer guidance or hiring experienced professionals is recommended.

How long does a professional cleaning take?

Timing depends on deck size, condition, and access. Most residential composite decks can be completed in a few hours to a day. We provide a time estimate during the on-site assessment.

Do you protect plants and outdoor furniture?

Yes. We take steps to protect landscaping and outdoor items by rinsing plants, isolating areas, and using targeted application techniques when applying cleaning solutions.

Call to action

If your composite deck needs attention, Code 3 Cleaning can assess the condition and recommend a safe, effective cleaning plan. We’re firefighter-owned, fully insured, and serve Kenosha County, WI and Lake County, IL from our base at 11452 14th Ave, Pleasant Prairie WI. Call us at 224-381-0033 to schedule an assessment, or visit our contact page to request a callback. For more on other exterior services we provide, see our house washing page.

Address: 11452 14th Ave, Pleasant Prairie, WI. Phone: 224-381-0033. Fully insured and locally owned by firefighters who care about safe, quality work in your neighborhood.