It’s 2025—Don’t Tell Me You Still Don’t Know How to Remove Mould from Decking

Mould isn’t just an eyesore; it’s your decking’s worst enemy, capable of causing long-term damage if ignored. Whether your deck is made of composite or wood, mould and mildew love to thrive in damp, humid environments. But don’t worry—this guide is here to tell you how to remove mould from decking! From simple cleaning hacks to pro-level prevention tips, you’ll learn everything you need to banish mould for good and keep your deck looking pristine for years to come.

1. What Causes Mould on Decking?

Mould on decking is a common issue for homeowners, particularly in regions with high humidity or frequent rainfall. Mould thrives in areas with excessive moisture, and when left untreated, it can lead to the deterioration of your deck. Here’s why mould forms on decking:

Moisture Exposure: Decking that absorbs moisture, such as untreated wood or uncapped composite boards, becomes a perfect breeding ground for mould.

Warm, Damp Conditions: Mould spores require warm and moist environments to grow, and outdoor decks are often exposed to such conditions.

Natural Materials: Organic materials like wood and unprotected composite decking are particularly susceptible to mould growth because the fungi feed on the organic matter.

2. How to Remove Mould from Decking?

Removing mould from decking is easier than you think. Whether you have wood decking or composite decking, the process is similar. Follow these simple steps to restore your deck to its original condition.

Step 1: Clear the Deck Area

Start by removing any furniture, plants, or debris from the decking. This will give you easy access to the entire surface and prevent dirt from mixing with your cleaning solution.

Step 2: Sweep the Deck

Use a broom or brush to remove dirt and loose debris. Sweeping the deck helps prevent dirt from scratching the surface while you clean the mould.

Step 3: Prepare the Cleaning Solution

For a basic cleaning solution, mix a bucket of warm soap water. Alternatively, use a composite deck cleaner for more stubborn mould. Check with your decking supplier for any specific recommendations on cleaning products, as some materials may require special care.

Step 4: Apply the Cleaning Solution

Apply the soapy water or deck cleaner generously to the affected areas. Cover the entire surface to ensure the cleaning solution soaks into the mould and loosens the spores.

Step 5: Scrub the Deck

Using a brush with stiff bristles (preferably a deck brush), scrub the deck surface in a circular motion. Focus on the mould spots, but make sure to clean the entire surface for a thorough clean. For stubborn stains, you may need to scrub a bit harder.

Step 6: Let the Solution Sit

Allow the cleaning solution to sit on the deck for about 10-15 minutes. This will help break down stubborn mould and mildew stains.

Step 7: Rinse the Deck

Thoroughly rinse the deck with clean water, making sure all the cleaning solution and mould residue are washed away. If you’re using a pressure washer, use a low pressure setting to avoid damaging the deck. Keep the nozzle at least 12 inches away from the surface.

Step 8: Dry the Deck

Let your deck dry completely before placing any furniture or plants back. This helps prevent new mould growth, as mould thrives in damp environments.

3. How to Prevent Mould from Growing on Decking?

Now that you know how to remove mould from decking, the next step is to prevent it from returning. Regular maintenance and cleaning are key to keeping mould at bay. Here are some tips for long-term protection:

Tip 1. Regular Deck Cleaning

To prevent mould from developing, clean your deck regularly. Sweeping away dirt, leaves, and other debris prevents moisture from accumulating on the surface. Use a mild soap and water solution for routine cleaning.

Tip 2. Ensure Proper Drainage

Make sure your deck has proper drainage to prevent water from pooling. Standing water is the main culprit for mould growth, so good ventilation and drainage are essential.

Tip 3. Apply a Deck Sealant

For added protection, especially on wood decking, apply a deck sealant. This will reduce moisture absorption and protect your deck from the elements. If you have composite decking, consider using a product specifically designed for composite surfaces to help repel moisture.

Tip 4. Use a Protective Cover

If you live in an area with frequent rain or high humidity, consider using a protective cover for your deck during the off-season. This will keep moisture and organic debris away, reducing the risk of mould growth.

Tip 5. Keep Decking Dry

After it rains, ensure the deck dries as quickly as possible. You can help speed up the drying process by using a towel or mop to soak up excess water.

4. How to Keep Your Deck Mould-Free All Year Round?

Mould doesn’t have to take over your deck. By following the steps outlined in this guide on how to remove mould from decking, you can easily restore your deck’s appearance and prevent further damage. Regular cleaning, proper maintenance, and using the right protective measures will help keep your deck in excellent condition for years to come.

If you’re looking for high-quality composite decking that’s resistant to mould and mildew, consider Feelingwood Composite Decking. With its durable, low-maintenance design, it’s the ideal solution for creating a beautiful, long-lasting outdoor space.