How to Clean Vinyl Siding Mildew

Learn why it appears, how to clean it, and how to prevent

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When you notice mold on the vinyl siding of your house, there are always a lot of questions. Why it appeared, how to get rid of it, and what you could do to prevent it from spreading in the future. Moldy siding doesn’t look nice but except for that, it can become a cause of certain problems and issues!

In this article, we will explain what to do in this case. You will learn more about cleaning mold off vinyl siding. Also, we will provide you with detailed cleaning instructions. In addition, you are going to find out what makes mold and mildew appear on vinyl house exteriors at all and what measures could be taken in order to make it stop spreading and occurring.

How to Clean Mold From Vinyl Siding

Dealing with mold on siding of house is a task that many homeowners dread. How exactly do you remove mold from your vinyl siding? You might assume that a thorough scrubbing with a stiff brush will do the trick, but despite your most vigorous efforts, mold can be quite tenacious! This is not a problem that can be easily brushed off, and it requires considerable effort to eliminate. When you are confronted with mold on siding of house, there are a couple of significant methods at your disposal.

Mold on siding of house is not just an aesthetic issue but can cause serious damages if not dealt with correctly. Therefore, the solutions to address this problem should be equally potent and effective. In essence, overcoming the challenge of mold on siding of house is not an easy task, but with the right tools and approach, it can be handled effectively.

Worker plans to clean mold

Pressure Wash It

This is a great and quick option for cleaning vinyl siding mold problems. However, you need to take into account that pressure washing can be useful only if done professionally. Otherwise, if it is improperly done, pressure washing can damage your vinyl siding, making a hole through the vinyl cover and causing dents and warped areas! 

Besides, concentrated pressure washing can also leave streaks or water marks across the front of vinyl siding. Those can be pretty hard to remove afterward, which means you will have a lot of extra work and an extra headache!

In case you decide to pressure wash your vinyl siding yourself, make sure to use a few precaution measures: 

  1. Use the widest setting on the pressure washer
  2. Point it straight at the siding, not at an upward angle
  3. Move the nozzle constantly and don’t focus on one spot too long!

If you do everything correctly, with the help of pressurized hot water mixed with a mold-killing agent you will do wonders at cleaning off that nasty mold growth on your house’s exterior!

How to Clean Vinyl Siding Mildew

There is one more thing you should keep in mind should you consider pressure washing as your anti-mold remedy. Some mold cleaning products contain chemical agents that can kill mold long before it has a chance to grow! If you use a cleaner like that, you will not only keep the mold away, but you will also be able to have longer periods between your home siding cleanings!

Prepare a Homemade Vinyl Siding Cleaner

If you are not sure that you will be able to handle a pressure washer (since this tool needs some physical strength!), or that your old siding will survive pressure washing at all, you can opt for a simpler solution instead. 

Water and vinegar can be used to prepare a useful and easy anti-mold solution. Of course, in this case, you will have to spend some elbow grease! What will you need for that? Well, you need to mix 30% white vinegar and 70% water. Like that, you get a great all-purpose vinyl siding cleaner! 

This solution will remove light mold and mildew stains easily. But you need to know that, if your mold is stubborn and it is spread widely around the siding surface, you might want to consider using a stronger cleaning solution to cope with it! 

For a stronger homemade siding cleaner, mix together the following ingredients:

  • 1 gallon of water
  • 1/3 cup powdered laundry detergent
  • 2/3 cup powdered household cleaner
  • 1 quart of liquid laundry bleach

Of course, cleaning your siding manually will take a lot of time and effort, as well as a lot of intense scrubbing. But at least, you will not be using harsh chemicals or way too strong cleaning methods like pressure washing that requires a skilled operator.

At this point, we would like to warn you that bleach is not always recommended for mold cleanups! Using bleach can sometimes cause problems with the siding materials you are cleaning. Luckily, if you have siding that’s made of vinyl, there is no need to worry since vinyl siding can withstand bleach easily. 

So, now you know what methods to use to clean mold off your vinyl siding. We’d recommend you a homemade solution for the cases when mold is not too old or widespread, as well as for the sidings that are old enough and might not survive a stream of water under high pressure. Pressure washing will work better on old mold and mildew though.

What Makes Mold Appear On House Siding

If you notice mold on your house’s exterior, you will definitely become curious about where it came from and what made it occur. In fact, there are typically two major causes of mold and mildew on the exterior walls of our houses.

Moisture and lack of light are the two key factors that lead to mold and mildew growth. You have probably seen mold or mildew in a crawl space many times, as well as in your basement, or in a poorly ventilated bathroom. This mostly happens because those places are poorly lit and have high levels of moisture. However, your home’s exterior can also be a target for mildew and mold to grow!

But why does it happen, you may wonder? What do basements, moist bathrooms, and crawl spaces have in common with your house’s siding? In fact, they do have several common features.

  1. Accumulated moisture from humid air
  2. Lack of light

See, a house’s siding is a place that is often covered in small particles of dirt and environmental debris. When water sits on such a surface for a long time, it becomes an ideal environment for different fungi spores to grow. After a while, if not cleaned regularly, this spore growth produces visible mold and mildew.

If you take a closer look at mold or mildew growing on your home’s siding, you will probably notice that these moldy stains only grow on the north-facing side of the house. Also, they can occur where trees and other high plants (like bushes) have grown too close to the siding and created shady spots. 

These shaded areas, as well as the north side of your house, receive very little direct sunlight. As a result, moisture doesn’t have a proper chance to evaporate (if has it at all!), and all the water just remains on your siding, creating the perfect habitat for mold and mildew spores.

Is Moldy Siding Dangerous?

The question on many homeowners' minds is - "How hazardous is black mold on siding?". Undeniably, black mold on siding diminishes the aesthetic appeal of your home, but the problems it presents go beyond the superficial.

Primarily, if black mold on siding is merely on the surface, it can still be effectively managed. The best way to clean mildew off vinyl siding becomes your top priority and should be addressed swiftly. However, the predicament escalates when this troublesome growth makes its way behind the siding!

Black mold on vinyl siding is not only unattractive but also a potential threat to your house's structure. It thrives on materials such as wood, drywall, and insulation. As it feeds on these materials and proliferates, it generates spores that infiltrate your ventilation system. The black mold on vinyl siding, in this case, isn't just a cosmetic issue; it's a health concern. These spores, when inhaled, can induce severe illnesses and various respiratory problems.

It becomes even more crucial to clean mildew from vinyl siding when we understand the potential hazards. This understanding also amplifies the importance of the best way to clean mildew off vinyl siding. It's not just about keeping your home looking its best - it's about preserving its structure and protecting the health of those within it.

Mold feeds on wood, drywall, and insulation. And while it is feeding on these materials and is spreading, it reproduces spores that are being released through your ventilation system. Those spores are extremely harmful to anyone living in the home! See, they can lead to severe illness and different respiratory issues once inhaled. 

Besides, there is one more issue. Once mold makes its way inside the home, it is basically impossible to get rid of. Should this happen, you will most likely have to replace all of the structures affected by the mold!

This is why it is mandatory to check your house’s exterior for the tiniest signs of mold or mildew regularly, especially if you live in an area that has a humid climate or your house gets little sunlight for different reasons. Like that, you will be able to spot the earliest signs of infestation and get rid of it rather than dealing with the huge problem later when mere cleaning won’t help.

How to Prevent Mold On Siding

If you already have mold on your vinyl siding, there is still a chance for you to fight it since now you know a few handy and effective cleaning methods. However, it is always better to prevent the problem in advance. This is why we strongly recommend you learn a few precautionary measures that will help you keep mold spores at bay.

Remove All the Sources Of Moisture That Can Cause Mold Growth 

As you already know, mold and mildew both like shady and moist locations. So if you have trees and/or shrubs growing too close to your home, keep in mind that they prevent sunlight from evaporating moisture off the siding. You should either cut them short or trim to let more sunlight or remove them at all if possible.

Also, pay attention to climbing vines or moss. It is important to avoid ivy, vining plants, and moss growing on your house. These plants work as a sun-protecting shield, obscuring the sunshine and attracting moisture instead. As you can guess, it can cause deterioration of any type of exterior cladding.

Mind Gutter Leakage Or Overflow!

What does gutter have to do with mold, you might be wondering? In fact, clogged or improperly sloped gutters cause water damage that can affect your siding! And not only siding but also your roof, and even foundation! This is why you need to be sure to deal with this type of issue as soon as possible if you have it. This will help you to avoid widespread damage to your home.

Remember to Check Your Sprinklers

In particular, you should check whether they are properly installed. See, if sprinkler heads are placed in the wrong spots, or if they are located too close to your house, they can direct water right towards your siding rather than your lawn! As a result, such a “watering” will cause mold and mildew development pretty soon. So make sure you check where your sprinklers are placed and their coverage as well to make sure your siding is safe and won’t be watered.

Don’t Forget About Your Dryer Ventilation

Your dryer vent produces steam, which can encourage mildew and mold growth as well. The solution to this problem is simple: simply make sure your dryer is venting into a space that isn’t enclosed. It should also be not blocked by foliage. The key point is that all the excess moisture should have somewhere to go!

Maintain Your Siding Regularly

When you maintain your siding properly and regularly, this is the key to noticing any potential sources of mold or mildew damage early. Luckily, siding maintenance is nothing difficult:

  • Inspect your siding regularly by taking a walk around your house to check its condition. Like this, you will be able to see and stop the earliest mold and mildew growths, as well as catch any other siding issues before they spread.
  • Reseal or repaint your siding. Your house’s siding requires regular care to protect it from moisture. It’s recommended to reseal it every couple of years and repaint it every five years.
  • Keep your siding clean. Remove dirt, grime, mold, and mildew from its surface as soon as you notice them. Don’t wait until they spread!

If you have wooden siding, note that it requires even more care and attention than the siding made of vinyl since wood is more prone to mold and mildew damage!

Well, now you know more about what makes mold grow on your vinyl siding and what you should do if you notice the first and the earliest signs of this disaster on your facade. Vinyl is believed to be a durable material that requires little care and maintenance, which is why quite many homeowners tend to neglect proper maintenance and regular cleaning.

However, even vinyl should be kept in a decent condition if you want to keep it mold-free and protected from mildew. And with the help of the tips and life hacks we shared with you today, you will definitely succeed!


I urge you to adhere to the following instructions when cleaning mildew from vinyl siding to ensure your safety and the integrity of the construction site:
  1. Personal Protective Equipment (PPE): Always wear PPE such as safety glasses, gloves, and a dust mask when cleaning mold to protect yourself from the mold spores.
  2. Secure Your Work Area: Before you begin, secure the area to prevent any unsuspecting individuals from walking into your workspace. Use caution tape if necessary.
  3. Ladder Safety: If using a ladder to reach high areas, ensure that it's stable before climbing and maintain a 3-point contact (two hands and a foot or two feet and a hand) at all times.
  4. Handle Cleaning Agents with Care: If you're preparing a homemade cleaning solution, ensure you do so in a well-ventilated area. Be mindful of combining chemicals, as some can react adversely.
  5. Pressure Washing Precautions: If using a pressure washer, maintain a safe distance from the siding to prevent damaging the surface or injuring yourself. Never point the washer at people, animals, or windows.
  6. Bleach Precautions: If your cleaning solution contains bleach, avoid getting it on your skin or in your eyes. If contact does occur, rinse immediately with plenty of water.
  7. Proper Disposal: Dispose of your cleaning solution safely to avoid harming the environment. Do not pour it into water sources or storm drains.
  8. Dehydration and Overexertion: Take regular breaks when cleaning, especially if the weather is hot. Keep yourself hydrated.
  9. Post Cleaning Inspection: After cleaning, inspect the siding for any signs of damage. If you find any, report it to your supervisor promptly.
  10. Regular Maintenance: Regular maintenance is the key to preventing mold growth. Inspect the siding regularly and clean as necessary.

Remember, safety is everyone's responsibility. Follow these instructions to ensure that you are cleaning your vinyl siding mildew in the safest manner possible.



Frequently Asked Questions

Why Does Mold Appear On Vinyl Siding?

Mold appears due to a combination of moisture, warmth, and nutrients available on the vinyl siding. These conditions are often present in the areas shaded from sunlight.

How Do I Get Rid Of Mold On Vinyl Siding?

You can get rid of mold either by pressure washing it or by using a homemade cleaning solution. Both methods are effective, but their use depends on the extent of the mold and the condition of your siding.

Can I Prevent Mold From Appearing On My Vinyl Siding?

Yes, maintaining cleanliness, improving ventilation, and reducing moisture can help prevent mold growth on your vinyl siding.

Is Mold On Vinyl Siding Dangerous?

Besides being aesthetically displeasing, mold can degrade the quality of your siding over time. Also, some types of mold may cause health issues if inhaled.

Can Pressure Washing Damage Vinyl Siding?

Yes, if done improperly, pressure washing can cause damage such as holes, dents, and warped areas on the vinyl siding.

How Do I Properly Pressure Wash My Vinyl Siding?

To pressure wash correctly, use the widest setting, aim straight at the siding, and keep the nozzle moving so as not to focus too long on one spot.

What Is A Good Homemade Cleaner For Vinyl Siding?

A good homemade cleaner can be made by mixing 30% white vinegar and 70% water. For a stronger solution, you can add laundry detergent, household cleaner, and bleach to water.

Is Bleach Safe For Vinyl Siding?

Yes, unlike some other materials, vinyl siding can withstand bleach, making it a suitable ingredient for a homemade cleaning solution.

Can Mold Come Back After Cleaning?

Yes, if the conditions favorable for mold growth persist, the mold can come back after cleaning.

Should I Hire A Professional To Clean My Vinyl Siding?

Hiring a professional is advisable if you are not comfortable using a pressure washer or if your siding is old and delicate.

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