In South Carolina, we’re no strangers to heat, humidity, and the growth of algae and mold on the sides of our homes. If you’ve noticed green, black, or brown streaks on your siding, you’re not alone. It’s a common issue for homeowners in our area, and while it might seem like a minor cosmetic problem at first, it can turn into something much bigger if left unchecked. At Palmetto Exterior Washing, we’ve cleaned many homes over the years, and one of the most frequent things we deal with is organic growth on siding. Algae, mold, and mildew come from the same root cause: moisture.
In this blog, our house washing experts will explore how algae and mold grow, what this means for your home, and what you can do about it.
What Causes Algae and Mold to Grow on Siding?
The siding on your home is constantly exposed to the elements. When moisture from rain, morning dew, or even nearby vegetation doesn’t dry properly, it creates the perfect environment for algae and mold spores to settle in and grow. You’ll usually see algae and mold show up more heavily on the north-facing side of a home, or in spots that don’t get much sun. That’s because sunlight helps dry things out; without it, moisture tends to linger longer. Add dirt or organic debris from trees, and suddenly you have a breeding ground.
Vinyl, wood, stucco, and even brick siding can all be affected. While the material might change, the problem stays the same: trapped moisture and lack of sunlight.
What Does It Look Like?
Algae typically appear as green or black streaks, often running down from gutters, windows, or shaded areas. Mold can look like dark blotches or patches, and mildew tends to have a powdery texture that spreads across flat areas. At first glance, many homeowners think it’s just dirt, but once it spreads, it becomes clear that it’s something else entirely. And the longer it sits, the deeper it settles into the surface.
Why It’s More Than Just an Eyesore
It’s easy to think of algae and mold as cosmetic issues, but they can cause real damage if ignored. For one, mold and mildew can degrade certain types of siding over time, especially wood and older vinyl. Moisture seeps in, the surface becomes stained or warped, and eventually, costly repairs are required. There’s also the health aspect to consider. Mold spores can contribute to allergies and respiratory issues, especially if they find their way inside the home. If you have children, elderly family members, or anyone with a sensitive immune system, keeping mold at bay is a safety concern.
And then there’s curb appeal. Even if your home is structurally sound, visible algae and mold can make it look neglected. That can affect your home’s value, especially if you’re considering selling.
What You Can Do About It
The good news is that you don’t have to live with it. The proper cleaning method allows algae and mold to be safely and thoroughly removed from your siding. At Palmetto Exterior Washing, we use a soft washing process specifically designed to treat your exterior surfaces gently while killing and removing the organic growth. Unlike high-pressure washing, soft washing uses safe, eco-friendly cleaning solutions that break down the algae and mold at the root rather than just blasting off the top layer. That means it stays gone longer and doesn’t risk damaging your siding in the process.
Regular exterior cleaning also makes it harder for algae and mold to return. By removing dirt, pollen, and other debris, you’re taking away the food sources these organisms rely on to grow. We recommend a professional pressure washing at least once a year for most homes in our climate.
Book Your Exterior Washing in Charleston with Palmetto Exterior Washing
Algae and mold on your siding might start as a small streak or stain, but if left alone, they can quickly grow into a bigger problem. They can affect the look of your home, its structural integrity, and even your health. If you’re noticing signs of growth on your siding, don’t wait until it worsens. Our comprehensive soft and pressure washing services are here to help.
At Palmetto Exterior Washing, we’re happy to come out, take a look, and recommend the best solution for keeping your siding clean, healthy, and looking great all year round. Reach out today to learn more about our soft and power washing services in the Charleston, SC, area.