If you have noticed dark or black streaks running down your roof, you are not alone. These stains are common on homes throughout Kentucky, where humidity, rain, shade, and changing seasons can encourage organic growth. While black streaks can make a roof look older and dirtier than it actually is, understanding what causes them can help you choose the right cleaning method.
What Are Those Black Streaks?
In many cases, the black streaks you see on asphalt shingles are caused by a type of algae called Gloeocapsa magma. This airborne algae can settle on a roof and thrive in areas where moisture tends to linger. Over time, the algae can spread across shingles, creating dark discoloration that becomes increasingly noticeable. Roof sections that receive less sunlight may be especially susceptible because they remain damp longer after rain or morning dew.
Algae is not the only organic growth that can appear on a roof. Moss and lichen can also develop in damp or shaded conditions. Moss, in particular, can retain moisture against roofing materials, making it important to address significant growth rather than simply ignoring it.
Why Pressure Washing Isn’t the Answer
When homeowners see a stained roof, their first instinct may be to wash away the discoloration with high-pressure water. However, a roof is very different from a concrete driveway or other hard exterior surface.
Using excessive pressure on asphalt shingles can damage the surface and dislodge protective granules. Instead, professional roof soft washing uses low-pressure water and appropriate cleaning solutions to treat organic buildup without relying on aggressive force.
The cleaning solution targets algae and other organic growth so it can be removed safely. Depending on the type and severity of the buildup, some moss or lichen may take additional time to fully release from the roofing surface after treatment.
Keep Your Roof Looking Its Best
Notably, algae, moss, lichen, and other organic buildup to remain can leave your roof looking neglected and may contribute to moisture-related concerns over time. Periodically checking your roof for dark streaks and other signs of growth can help you address problems before they become more widespread.
If black streaks are taking over your roof, avoid reaching for a pressure washer.
Bourbon Capital Softwash uses low-pressure soft washing to safely clean roofs throughout Bardstown, Louisville, and Central Kentucky. Reach out to us to learn more about professional roof washing and give your home a cleaner, well-maintained appearance.
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