Why Did My Siding Turn Green?

Vinyl siding is a relatively recent material for the exterior of homes, debuting in the 1950s as a more cost-effective alternative to other siding options on the market, but still just as strong and durable. Immediately, homeowners lined up to outfit their homes with attractive, storm resistant, yet a half-the-price option, sending vinyl skyrocketing into popularity by the 1970s.

siding turns green

However, as the weather broke and homeowners finally stepped outside for the first time in what seemed like months, they noticed something amiss…green discoloration. Even modern vinyl siding cannot escape these hideous green blemishes, but what’s the cause of it? Is there anything you can do about it?

The Causes Behind Your Green Siding

Vinyl siding can do a lot.  It can withstand UV degradation, it can beat out harsh Midwestern winters, it can hold its own against fearsome gusts of wind and it insulates your home for both the hot and cold seasons. As with every material on the market, there’s bound to be a disadvantage. Vinyl’s only flaw is that algae, mildew, and mold are prone to grow on its surface naturally over time.

Algae may appear green or brown and will continue to stay damp against the surface of your vinyl siding. Its growth won’t cause any underlying damage, and if the vinyl has a presence of dirt and dust, the algae will use this to feed and grow.

The warm environment allows the algae to spread more rapidly, and thrive, so green discoloration is certainly something homeowners are more likely to see during the spring and summer seasons.

Mold, however, is a result of excess moisture and will appear as green discoloration against your siding. The reason for its growth can be attributed to an issue with your gutter system or a leaky drainpipe, which is why the tedious chore of checking and cleaning your gutters twice per year is so important. Mold can be harmful and should be addressed immediately, even if it’s portioned off to growing on the home’s exterior.

Similarly, mildew can grow and discolor siding to the ugly splash of green you’ll see, especially in when the weather begins to turn, due to a lingering presence of moisture.

How to Get Rid of the Green on Your Siding

You don’t have to pull your hair out fretting over whether or not the green discoloration is permanent—it’s not. In fact, you can even tackle its removal yourself with a bucket of warm water and dish detergent as your first step.

green siding

Regardless as to whether the green discoloration is from algae, mold, or mildew, the majority of it should respond to the solution, coming off when you go to scrub with a bristle brush and wipe with a rag.

Depending on how stubborn the mold is you may need to use something stronger than dish soap. To step it up a notch, load up your arsenal with a mixture of water and chlorine bleach, using this to scrub your discolored siding with a stiff-bristled brush, moving from side to side over the greener areas.

When the green has disappeared and the vinyl siding is finally rid of the algae, mildew, and mold, hose down the exterior of the house with a garden hose.

You’ll want to point the hose down to avoid spraying the water behind the siding, otherwise, the water will become trapped beneath, and this leads to a slew of further mold and mildew problems.

Power-Washing Away the Green on Your Siding

For some homes, the green seems to be overtaking the vinyl siding in just about every corner, and so power-washing can be the best option as opposed to a brush and chlorine mixture. The force of the water will penetrate through the growth of the algae, while also working to restore the vinyl clear of any dirt and debris.

A good power-washing job will make your vinyl siding look like brand new again. You can certainly do this yourself, as you did with washing the green off your house with mild detergent and the aid of a garden hose, but it’s always safer and easier to hire a professional.

Professional power-washers know how to utilize their tools to spray the vinyl siding without causing damage. Believe it or not, you can’t just simply aim a power-washer at the side of a home, you must use the equipment in such a way and move the water in a pattern so that you don’t puncture it or leave water trapped behind the vinyl paneling.

It isn’t uncommon for homes to require power-washing once a year when spring rolls around, as algae, mildew, and mold quickly form once the warm weather hits and can grow and spread.

Replacing Your Vinyl Siding

Neglected homes and fixer-uppers may need new siding in their entirety. Yes, you can power-wash these homes all day and night, but there comes a time where vinyl siding serves out its lifetime and can no longer perform to its greatest capabilities.

If your home’s siding is chipped, distorted, and even wavy in some places, it’s probably time to replace it. If your vinyl siding is from decades ago, consider upgrading, as modern vinyl is more resistant to discoloration, UV radiation, shock resistant, and insulating, all advantages that are worth the expense.

Finding a reputable siding company that measures and installs vinyl siding the correct way makes a big difference. Our installation team and representatives will help you choose the right siding colors, styles and options to make your home stand out.

On top of that, you’ll receive award-winning vinyl siding that is tested to withstand strong weather conditions and Midwest seasons. Speak to a product specialist and get a free quote online today.

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