How to Clean Composite Decking: A Complete Step-by-Step Guide

Composite decking is a popular choice for outdoor living spaces thanks to its durability, weather resistance, and minimal upkeep. In this guide, you’ll learn exactly how to clean composite decking safely and effectively, without damaging its surface or colour. We’ll also share tools, techniques, and tips used by experienced Calgary deck builders.

Why Cleaning Composite Decking Still Matters

While composite decking is low maintenance compared to traditional wood, it’s not maintenance-free. Dust, pollen, mold, and grime can collect over time, especially in shaded or damp areas. Regular cleaning not only improves the appearance but also extends the lifespan of your deck by preventing surface buildup and stains.

Tools You’ll Need to Clean Composite Decking

You don’t need anything fancy to keep your composite deck looking sharp. Gather these items before getting started:

• A garden hose with a spray nozzle or a pressure washer (under 3,100 PSI)
  
• A soft-bristled brush or broom
  
• A bucket
  
• Composite decking cleaner (or mild dish soap for light dirt)
• Gloves and safety glasses (optional but smart)

Step-by-Step: How to Clean Composite Decking

1. Clear the Deck Surface

Remove patio furniture, planters, BBQs, or anything else sitting on the deck. This ensures you won’t miss spots and lets the entire surface dry properly afterward.

2. Sweep the Surface

Use a soft-bristled broom to remove loose dirt, leaves, and debris. Always sweep with the grain of the boards to prevent scuffing the finish.

3. Rinse with Hose or Light Pressure Washer

Spray the deck from one end to the other, focusing on corners where debris gathers. Avoid using a zero-degree nozzle to prevent damage.

4. Apply a Composite Decking Cleaner

Use a cleaner designed specifically for composite materials. Follow the instructions on the label and avoid bleach-based products. Use a bucket and brush to apply the solution in sections.

5. Gently Scrub Tough Spots

Focus on stained or heavily soiled areas using a soft-bristled brush. Don’t over-scrub, let the cleaner do most of the work.

6. Rinse Thoroughly

Use your hose or pressure washer to rinse off all remaining cleaner and loosened dirt. Don’t leave any cleaner behind, as residue can affect the deck’s appearance over time.

7. Let It Dry

Let the deck air dry or use towels if needed. Avoid placing furniture or rugs back on the deck until it’s fully dry to prevent mold or streaks.

Pro Tips from Calgary Deck Builders

• Avoid metal shovels or wire brushes, they can damage the composite finish.
• Clean spills like grease or wine immediately to prevent staining.
• For mold or mildew, use a composite-safe cleaner labeled as mildew-resistant.
• In snowy climates like Calgary, regularly sweep off snow and debris during winter.

Internal and External Resources

Explore our composite decking installation services in Calgary to upgrade or replace your current deck.

For detailed product guidance, check the Trex Cleaning Guide for care instructions based on manufacturer recommendations.

FAQs About Cleaning Composite Decking

How often should I clean my composite deck?
At least twice per year, ideally in spring and fall. More often, if your deck is shaded or near trees.

Can I use vinegar or bleach?
Avoid bleach. Vinegar mixed with water can be used in light amounts, but may not be as effective as a composite-specific cleaner.

Is pressure washing safe for composite decking?
Yes, if done with care. Use a fan tip and keep the pressure under 3,100 PSI. Always test in a small area first.

What’s the best time of day to clean my deck?
Early morning or late afternoon, avoid peak sunlight to prevent the cleaner from drying too quickly.

Do I need to seal composite decking after cleaning?
No sealing is required. Composite materials are designed to resist weather and fading without sealants.

With just a few basic tools and a little know-how, cleaning composite decking becomes a quick seasonal habit instead of a dreaded chore. With regular care, your deck will stay beautiful, safe, and enjoyable for years to come. 

Ready to skip the hassle and let the pros handle it? Hire Project Landscape for expert composite deck cleaning, maintenance, or installation in Calgary, built to last, built for life.