Picture a cottage in the woods. Branches wrap around the asides as moss climbs the foundation, creating perfect spirals of greenery. It’s the perfect fairytale getaway, right out of a book. 

And it is perfect: in a fairytale.

In real life greenery on your home’s surface is the last thing you want. Overhanging branches can damage your roof. Moss on your foundation is a sign of water damage. 

And the worst green on your home? Algae. And here in Pennsylvania we sure have the perfect weather for it!

Algae loves to grow in damp climates and homeowners like us in rainy Schuylkill County know how big of an issue it can be. The good news is that finding the cause of the algae and removing it is easier than you might think. 

Let’s put aside the fairytale cottage fantasy and spend a moment today talking about how to keep a tidy, healthy exterior instead. 

Ready to say ‘goodbye’ to green stains on your siding and ‘hello’ to algae-free vinyl siding that shines like new? 

Read on!

Why Is There Algae On My Siding? 

Siding with Algae

If you’ve read our ultimate guide to facades you already know vinyl siding is virtually maintenance free. That paired with the affordability is a big reason why vinyl siding is America’s most popular exterior covering.  

You might be asking, “If it’s maintenance free and designed to protect for decades…then why is there algae growing on my siding?!”

A few reasons! 

Not all siding is made equally. Martin Roofing & Exteriors uses high-quality products from PlyGem- but there are other manufacturers that produce thinner, less expensive options. And, in general, the cheaper the siding- the less durable it will be long term.  

Did you know removing algae isn’t maintenance…it’s really a repair? Think of it less like cleaning and more like resurfacing.

Rain and moisture are only the start, there are other elements that cause algae damage to your siding. 

Avoiding Algae Growth

Here are three things to look out for to avoid algae growing on your vinyl:

#1 Look for Overhanging Branches. If there are trees near your house, they can be the cause of your algae problem.

How? Tree sap and debris accumulates on your siding and over time these things create the perfect layer for algae to grow on.

Overhanging branches can also cause runoff water to hit against your siding, creating extra moisture for not only algae (and mold)!

Overhanging branches cost homeowners hundreds every year in repairs. 

#2 Is Your Siding Exposed to Sunlight? Life is all about balance, isn’t it? Too much sunlight can cause your vinyl siding to fade while not enough creates the right environment for algae growth. There’s not much you can do to expose your siding to more sunlight but you can regularly monitor shady areas for signs of growth.


#3 Check Your Gutters! Regular gutter upkeep is one of the most important preventative home measures you can take. If your gutters are clogged, rainwater isn’t diverted away from your house. This causes more than just algae damage- but roof and foundation damage, too. 

Once you’ve identified the cause of your algae growth, you’re ready to start removing it.

Algae Removal Do’s (and Don’ts)

Removing algae from siding

Grab a bucket of warm water, some bleach, and a brush. It’s time to get scrubbing! 

There are special cleaners you can pick up at most hardware stores but bleach works just as well. Use a 1:5 ratio (one part bleach to five parts water) for the job. You can also pick up a pump sprayer for difficult spots. 

Start from the top, and work your way down. Make sure to rinse the house down after scrubbing the algae. 

You should never try to power wash your own siding. If done incorrectly, the siding can become damaged, leading to costly repairs. 

If you’ve already tried a good scrub and the stains persist, call a professional to power wash it for you.

While You’re Up Close and Personal Cleaning Your Siding…

Home with vinyl siding

While you’re up close and personal with your siding, check for other signs of damage, including: 

    • Loose boards 
    • Warps or discoloration
    • Dents or cracks 

The great thing about vinyl siding is that often you only have to replace the damaged boards instead of all of the siding. 

Small issues could be signs of a larger problem. Loose boards and discoloration could be signs of water damage and should be taken care of immediately.  Make sure to have the damaged boards repaired and keep an eye on them. A trustworthy contractor will be able to give you a good estimate on how many years your siding has left, and how to prepare for the future. 

If algae goes untreated long enough, it can lead to mold. While this can be scary to find, it’s nothing to panic about. Scrub the boards down with vinegar and water instead of bleach. If the mold still persists, call a professional to power wash it. 

Want to know more about protecting your home’s siding from water damage? You can read about rainproofing your siding, foundation, and roof here! 

Healthy Siding- The Key to a Healthy Home

Contractors outside home

I hope after a good scrub your algae problems have disappeared. Sit back and give yourself a hearty congratulations on being a fantastic homeowner.

Here at Martin, we value your home’s health. My husband and his team have worked to keep our client’s vinyl siding happy and healthy in Schuylkill County for decades. If you’ve noticed damage that goes beyond a simple clean- we’re happy to help you repair or replace it! 

Give my husband a call at 570-345-0406, or click here to learn more about what our crew can do for you.  

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