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Can Sodium Hypochlorite Bleach Roof Tiles

By Mark Cave March 18, 2024 2 comments

Debunking the Myth: Can Sodium Hypochlorite Bleach Roof Tiles?

In the world of roof maintenance, one common misconception often leads homeowners astray—the belief that sodium hypochlorite, when used for cleaning, can bleach the color out of roof tiles. This assumption not only misrepresents the capabilities of sodium hypochlorite but also overlooks the real reasons behind the changes in appearance that tiles undergo over time. Mark Cave, an authority in the field, provides invaluable insight into why this belief is not only misguided but completely overlooks the actual causes of color fading in composite roof tiles.

soft washing roof tiles

The Misconception

Many assume that the application of sodium hypochlorite for roof cleaning results in the bleaching of tile color. This is a misunderstanding of the chemical's effect and the cleaning process. Sodium hypochlorite, a potent cleaning agent, is often used in the soft washing process for its effectiveness in removing organic growth and stains from surfaces, including roof tiles.

Sodium Hypochlorite For Soft Washing 14% to 15%

The Reality Behind Color Changes in Roof Tiles

Composite tiles are engineered for durability and aesthetic appeal. However, like all materials, they are subject to wear and tear over time. A key factor often overlooked is the erosion of the colored coating on these tiles. As Mark Cave points out, the real culprit behind the perceived color fading is not the cleaning solution but the natural wear of the tile's surface.

Nature's Camouflage: Black Staining

Black staining on roofs, often caused by algae and other organic materials, can mask the underlying condition of the tiles. These stains can create a uniform appearance that hides the wear and tear of the tile's surface. When a homeowner decides to clean their roof, employing soft washing techniques with sodium hypochlorite & clever wash surfactant, they're often surprised by the appearance of the tiles post-cleaning.

Clever Wash Surfactant for soft washing roof tiles

Unveiling the Truth

The cleaning process does not bleach the color from the tiles; rather, it reveals the true condition of the tile that was hidden under layers of staining. The erosion of the colored coating over time, coupled with exposure to the elements, leads to the natural degradation of the tile's appearance. The cleaning process merely unveils this condition, leading to the mistaken belief that the cleaner has bleached the tiles.

Gradual Cleaning with Biocides

For those concerned about the sudden reveal of tile wear, a gradual approach using biocides like soft wash pro 50 offers an alternative. This method slowly cleans the roof over an extended period, typically around 12 months, gently removing organic growth without the immediate contrast change. This can be a more palatable option for some, offering a less dramatic unveiling of the roof's condition.

Soft Wash Pro 50 roof tile biocide cleaner


The belief that sodium hypochlorite bleaches roof tiles is a misunderstanding of both the chemical's properties and the condition of the tiles themselves. The reality is that time and nature wear down the materials, and cleaning simply reveals the true state of the roof. Understanding this distinction is crucial for homeowners and professionals alike, ensuring that the right methods are employed for maintaining the aesthetic and structural integrity of roofing materials.

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  • Hello William,

    Thank you for your feedback and for sharing your thoughts. I’m glad you found the article refreshing and informative.

    You’re absolutely right—sodium hypochlorite (SH) is a widely used and highly effective solution for roof cleaning. While some in the industry might promote biocides through scare tactics, it’s important to understand the benefits and proper use of SH.

    When used correctly, sodium hypochlorite can safely and effectively clean roof tiles without causing damage. It’s essential to follow recommended dilution ratios and application methods to ensure the best results and maintain the integrity of the roof tiles.

    Thank you again for your insights. If you have any further questions or need more information, feel free to reach out.

    Best regards,
    Mark Cave
    SoftWash UK

    Mark Cave on

  • Refreshing read, and absolutely agree. Too many folk within the insdustry(particularly those selling biocide) use the scare tactic about using SH products on tiles. However, as your article points out, it is widly used and to great effect.

    William on

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