Algae is a green, slimy substance that can be found on many surfaces, including vinyl siding. It often grows in humid climates and thrives in areas where there’s more sun. Unfortunately, green algae can be a problem on vinyl siding. It not only looks terrible, but it also poses health risks to people and animals that come into contact with it.

If you have green algae on your vinyl siding, this article will show you how to remove it from your home’s exterior.

In this article, we will be discussing the following:

  • What is the best vinyl siding cleaner?
  • What is the best homemade vinyl siding cleaner?
  • How to remove green algae from vinyl siding?
  • Is Power Washing bad for vinyl siding?
  • How do you stop algae from growing on vinyl siding?

Before you start cleaning, let’s dive into this information first so no effort is wasted!


What Is The Best Vinyl Siding Cleaner?

This is a difficult question to answer because it depends on the severity of your green algae problem. On one end of the spectrum, you can buy a powerful commercial vinyl siding cleaner from your local hardware store. However, it will require that you wear protective gear and follow all instructions closely to use the product safely.

Here are our top 3 recommendations:

Charlie’s is an eco-friendly way to clean your exterior, non-toxic, and biodegradable. This is a multipurpose cleaner, so you get to use it beyond just your vinyl siding.

As practical as it is, you’ll break a sweat using this product because it needs to be scrubbed and rinsed multiple times for it to be most effective.

True to its tagline, it does get rid of mold and mildew in as little as 15 seconds. This cleaner needs no scrubbing; just spray away and watch your vinyl sidings become clean.

The downside? It could damage your plants and harm your pets, and if used indoors, expect a strong odor. Why? RMR-86 is a robust chemical-based cleaner. 

Multipurpose, bleach-less, fast-acting, affordable, and can clean up 4,000 square feet of surface area per gallon, you can’t go wrong with this option.

  • Simple Green Pro HD
  • Star Brite Stain Remover Vinyl Siding Cleaner
  • Zinsser Jomax House Cleaner and Mildew Killer

What if you want to go to the traditional route and concoct your own formula? Read the following section to find out what recipes you can use.


What Is The Best Homemade Vinyl Siding Cleaner?

70% water, 30% white vinegar will always be the best multi-purpose homemade cleaner – it really is that effective. However, if you need a more potent formula, below are our recommendations:

  • 70% water, 30% white vinegar 
  • 1/3 cup powdered laundry detergent
  • 2/3 cup powdered household cleaner
  • One qt liquid laundry bleach
  • 1-gallon of water

Let it sit, but don’t let it dry. Power wash or scrub and rinse.

  • 1/3 cup trisodium phosphate (TSP)
  • 1/3 cup powdered laundry detergent
  • One qt household chlorine bleach
  • 1-gallon hot water

Don’t let it dry. Let it sit for 10 minutes, then rinse.

  • 1/2 cup baking soda
  • 1/3 to 1/2 cup of water to form a paste

After applying the 70% water, 30% white vinegar, use the paste as a scrub. Rinse well.

While there are several ways to remove green algae from vinyl siding, the first thing you will want to do is identify the type of algae that is affecting your siding. If it’s black, brown, or red, then that means the growth is likely due to dirt and may not require any special treatment.


How To Remove Green Algae From Vinyl Siding?

Now that you know what cleaning agents to use, how do you remove the green algae from your vinyl siding? The steps are plain and simple: Spray. Scrub. Rinse. Repeat. 

  1. Spray your cleaning formula on your vinyl siding, let it sit for 10 – 15 minutes, but don’t let it dry. 
  2. Scrub the algae off (if you don’t have a power washer).
  3. Rinse. 
  4. Repeat the process until you’re satisfied with the job. 

The number of times you’ll repeat the process depends on how strong your cleaning formula is. Lastly, don’t forget to rinse your plants and grass as your final step, to remove any harmful residue. 


Is Power Washing Bad for Vinyl Siding?

Power washing is a popular choice when maintaining and cleaning any surface, and that includes vinyl sidings.

Some people are concerned about using power washers for fear they will strip away the surface of their home’s exterior, but that usually won’t happen as long as you don’t use too much pressure when cleaning with a power washer.

Power washing vinyl siding is a dangerous game to play for those who lack the proper training or equipment. The wrong pressure can damage your building in just minutes!

Power washing vinyl siding is a task that not many people are comfortable doing, and for a good reason. There is a risk of driving water behind the siding when power washing which could cause damage to drywall, insulation, or even the wiring within the wall. To avoid any unfortunate accidents at your home, you’ll need to put some precautions in place like ensuring that your power washer stream is pointed straight toward the house, so nothing else gets blasted away.

Keep kids and pets out of harm’s way when working around windows, doors, or plumbing connections. Really use caution with openings in general since they are potential safety risks too!


How Do You Stop Algae From Growing On Vinyl Siding?

Vinyl siding is a popular choice for many homes, but it’s easy to neglect these durable materials. As a result, they are prone to the all-too-common issue of mold and mildew buildup, which can cause expensive damage if left unchecked. Luckily, there are ways you can prevent this from happening in your home so that upkeep isn’t as burdensome!

  • Washing your house once or twice to remove tree saps, debris, dirt, and other contaminants that can make algae thrive.
  • Prune trees and bushes so that they don’t press against your vinyl sidings.
  • Inspect and Maintain your gutters and drainpipes.
  • Inspect your ventilation ducts to ensure that moisture does not accumulate.
  • Check and modify your sprinklers, ensuring that they are not in the direction of your vinyl sidings.

And, of course, a regular inspection of your vinyl sidings will go a long way to keep them in good condition, helping you avoid unwanted repair costs.


You’re Ready To Go!

We hope you’ve found this article helpful! If it has, please share the information with your friends and family on social media. You never know who might need some vinyl siding upkeep tips themselves.

As the seasons change and we prepare for a new year, it’s time to assess your home. Not only does mold look awful on vinyl siding- which is why you want to protect it in the first place- but left untreated, mold can become hazardous to your health.

It’s essential to keep in mind that prevention is the best way to avoid costly repairs.

Editorial Contributors
avatar for Matt Greenfield

Matt Greenfield

Matt Greenfield is an experienced writer specializing in home improvement topics. He has a passion for educating and empowering homeowners to make informed decisions about their properties. Matt's writing focuses on a range of topics, including windows, flooring, HVAC, and construction materials. With a background in construction and home renovation, Matt is well-versed in the latest trends and techniques in the industry. His articles offer practical advice and expert insights that help readers tackle their home improvement projects with confidence. Whether you're a DIY enthusiast or a seasoned professional, Matt's writing is sure to provide valuable guidance and inspiration.

Learn More