ProClean Moss and Algae - Sodium Hypochlorite for Cleaning Paving: The Ultimate Guide to Removing Algae, Moss and Lichen

ProClean Moss and Algae - Sodium Hypochlorite for Cleaning Paving: The Ultimate Guide to Removing Algae, Moss and Lichen

ProClean Moss and Algae - Sodium Hypochlorite for Cleaning Paving: The Ultimate Guide to Removing Algae, Moss and Lichen

Paving slabs, patios, block paving and other hard surfaces naturally accumulate algae, moss, lichen and dirt over time. This not only makes outdoor areas look tired, but also creates slippery and unsafe surfaces. One of the most effective solutions for cleaning paving is sodium hypochlorite, a professional-grade chemical widely used in exterior cleaning.

In this guide, we’ll explain how sodium hypochlorite cleans paving, why it’s so effective, and how to use it safely for long-lasting results using ProClean Moss and Algae Cleaner.

What Is Sodium Hypochlorite?

Sodium hypochlorite is a chlorine-based cleaning solution and the active ingredient in many outdoor bleach products. It is commonly used by professional paving and patio cleaners because it kills organic growth at the root, rather than just removing surface dirt.

When applied to paving, sodium hypochlorite eliminates:

  • Algae
  • Moss
  • Lichen
  • Mould
  • Organic staining

This makes it far more effective than pressure washing alone.

Why Use Sodium Hypochlorite to Clean Paving?

Using sodium hypochlorite for paving cleaning offers several advantages:

  • Kills algae and moss spores, reducing regrowth
  • Restores the original colour of paving slabs
  • Improves safety by removing slippery growth
  • Reduces the need for high-pressure washing
  • Suitable for most paving types when used correctly

For patios and driveways heavily affected by biological growth, ProClean Moss and Algae Cleaner is one of the fastest and most reliable cleaning methods available.

If you're preparing surfaces before sealing, explore our full range of landscaping products to complete your project properly.

How Sodium Hypochlorite Works on Paving

Sodium hypochlorite works through oxidation. When it comes into contact with organic matter such as algae or lichen, it breaks down the cell structure, effectively killing the growth.

As the chemical reacts, you’ll often see:

  • Algae turning brown or white
  • Lichen bleaching and loosening
  • Black spots fading rapidly

Dead growth can then be rinsed away, leaving paving visibly cleaner within minutes.

How to Use Sodium Hypochlorite for Paving Cleaning

1. Prepare the Area

  • Sweep away loose dirt and debris or lightly pressure wash
  • Wet surrounding grass, plants and borders to help prevent chemical damage
  • Wear gloves, eye protection, respirator mask and suitable clothing

2. Dilute the Sodium Hypochlorite

Most paving cleaning jobs use a dilution between 1:5 and 1:10, depending on:

  • Strength of the product
  • Severity of algae or moss growth
  • Type of paving material

As with any chemical application, we always recommend carrying out a test patch first. Always follow manufacturer instructions and never mix sodium hypochlorite with other chemicals.

3. Apply to the Paving

  • Use a pump sprayer or low-pressure applicator
  • Apply evenly across the surface
  • Avoid overspray and windy conditions

4. Allow Dwell Time

Leave the solution to work for 10–30 minutes. Visible results often appear quickly as growth begins to die. Do not allow the chemical to dry out on the paving.

5. Rinse Thoroughly

Rinse with clean water. A light pressure wash can be used if required, but aggressive pressure is usually unnecessary once the organic growth is dead.

Is Sodium Hypochlorite Safe for Paving?

When used correctly, sodium hypochlorite is safe for most common paving materials, including:

  • Concrete slabs
  • Block paving
  • Sandstone
  • Limestone
  • Porcelain paving

However, incorrect use can cause:

  • Fading of jointing sand
  • Damage to nearby grass or plants
  • White residue if left to dry

Always test a small, inconspicuous area first, especially on natural stone.

Environmental and Safety Considerations

While sodium hypochlorite is highly effective, it should be used responsibly:

  • Prevent runoff into drains, ponds or watercourses
  • Keep pets and people away during application
  • Rinse surrounding vegetation after use
  • Store chemicals securely and out of direct sunlight

Once diluted and rinsed away, sodium hypochlorite breaks down into salt and water over time.

Pressure Washing vs Sodium Hypochlorite Cleaning

Pressure washing alone often removes visible dirt but does not kill algae spores, meaning growth can return quickly. Sodium hypochlorite treats the underlying cause, resulting in longer-lasting clean paving.

For best results, many professionals combine:

  • Chemical treatment with sodium hypochlorite
  • Light pressure washing for final rinsing

Conclusion: Is Sodium Hypochlorite the Best Way to Clean Paving?

For removing algae, moss, lichen and organic staining, sodium hypochlorite is one of the most effective paving cleaning solutions available. It delivers fast, visible results, reduces regrowth and restores paving to its original appearance when used correctly.

Whether you’re a homeowner cleaning a patio or a professional exterior cleaner, ProClean Moss and Algae Cleaner offers a reliable, cost-effective way to achieve professional-level results.

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