Wednesday, February 14, 2024
HomeFactsHow To Remove Stains From Asphalt Roof Shingles

How To Remove Stains From Asphalt Roof Shingles

Using Lime Water To Remove Scale White Lime Deposits Or Sarro

Removing Algae Stains From Roof Shingles

Finally, also from Wiki, we might later look at lime water softening – but I am very doubtful that it is quick enough to work as a roof cleaning procedure. I quote below

Softening can be achieved by adding lime in the form of limewater, Ca2, which, in a carbonatation reaction with CO2, forms calcium carbonate precipitate, reacts next with multivalent cations to remove carbonate hardness, then reacts with anions to replace the non-carbonate hardness due to multivalent cations with non-carbonate hardness due to calcium.

The process requires recarbonation through the addition of carbon dioxide to lower the pH which is raised during the initial softening process.

As lime is added to raw water, the pH is raised and the equilibrium of carbonate species in the water is shifted. Dissolved carbon dioxide is changed into bicarbonate and then carbonate . This action causes calcium carbonate to precipitate due to exceeding the solubility product.

Additionally, magnesium can be precipitated as magnesium hydroxide in a double displacement reaction.

The process is interesting in that both the calcium in the raw water as well as the calcium added with the lime are both precipitated. This is in contrast to ion exchange softening where sodium is exchanged for calcium and magnesium ions. In lime softening, there is a substantial reduction in total dissolved solids .

In ion exchange softening , there is no significant change in the level of TDS.

Reader update:


White Stains On Stone Roofs

The stone roof at above left has some normal light-colored areas that I do not think are a concern.

The white or light gray “stains” on the stone wall at above right can also appear on stone or slate or other roof materials. Lichens is not a stain in the proper sense of the word, but on asphalt, wood, or some other surfaces it can damage the roof and reduce its future life.

Worse, aggressive cleaning of lichens from a roof surface is likely to ruin asphalt roofing and other softer roof coverings.

Also see:

Choose The Right Chemicals

If you search online, youll see hundreds of posts on roof-cleaning methods. In less than 10 minutes, youll sign off convinced that all you need is a few gallons of household bleach and a power washer set at its lowest setting.

We dont recommend that approach. Even at low pressure, a power washer can seriously damage shingles. Plus, chlorine bleach is a corrosive agent that can damage metal roof flashings, gutters and downspouts. It can lighten the color of your roof and bleach anything the overspray contacts. And the runoff harms plants. But heres the kicker. Bleach may kill the top layer of algae and lighten the stains, but it doesnt kill the underlying algae. So the algae colony gets right back to work.

Sodium hydroxide products, on the other hand, work better than bleach and are less harmful to vegetation. But theyre also corrosive, and using them requires you to don full protective gear.

So look for a roof-cleaning product thats noncorrosive and safe for the environment. We chose Defy roof cleaner for this story , but there are other brands.

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What Algae Is Growing On My Metal Roof

The first question to ask is, What in the world is growing on my roof and turning my roof black, green, orange, or any color besides what it is meant to be? We highly recommend calling a roof cleaning professional and walking the property and identifying exactly what is growing on your metal roof and creating a plan of action to clean it. There are several types of algae that thrive on a metal roof surface.

Will Algae And Moss Growth Damage Asphalt Shingles

How to remove Rust stain : tip for cleaning asphalt ...

Algae will not damage asphalt shingles. It just looks terrible. But moss is a different animalits sponge-like and collects moisture. That moisture then sits on the surface of the roof for an extended period, keeping the roof wet. When this happens, shingles will curl and pull away from the underlayment, which weakens them. In a windstorm, the shingles can get torn off the roof and shorten its lifespan if you dont repair the roof.

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How To Clean Mold Off Roof Shingles

  • Written by Carol S. on Dec 13, 2009To ensure our content is always up-to-date with current information, best practices, and professional advice, articles are routinely reviewed by industry experts with years of hands-on experience.Reviewed by

Mold stains can form on roof shingles that are in permanent shade. These stains will discolor your roof and damage the shingles over a period of time if left alone. Extensive mold growth can also expose the interior of your attic or crawlspace to mold spores, carrying the problem over to the inside. Not to worry, though, because you can clean the mold off with basic household bleach and save your roof long before you need an expensive replacement. Follow the steps below to remedy this problem.

Protect Your Plants and Lawn

Splash the plants and parts of your lawn that are close to the sides of your house with water to protect them from the bleach solution. You can also cover them with tarps or plastic sheeting, which will protect the soil around your plants as well. Make sure that you create a wide radius around your home to be safe.

Make and Apply the Bleach Solution

Check for Cleanliness and Rinse

Allow the solution to soak into the shingles for at least 15 minutes. If they are severely molded, you may want to give it a little longer. Next, rinse the shingles thoroughly with a garden hose at low pressure. Start from the top shingle and rinse downward to prevent water seepage.

Take Precautions

How Do You Get Rid Of Black Streaks On Your Roof

Roof algae can be easily removed by a simple roof cleaning.

The important thing to know is that while an occasional cleaning shouldnât harm your roof, doing it yourself may void any roof warranties or homeowner insurance policies you may have.

An internet search on how to clean black streaks on your roof will turn up several different homemade formulas as well as commercial brands for getting rid of roof algae.

Most formulas contain chlorine bleach and/or trisodium phosphate and water. While lye is more effective than bleach, it is corrosive and should only be applied using full protective gear.

âOxygenâ bleach, commonly known as the brand name Oxyclean, can be effective and is less environmentally damaging, but will not work as well as formulas with chlorine bleach or TSP.

Remember that even chemicals that are safe for humans can still kill or harm landscaping and vegetation!

Cleaning the Roof Yourself

If you decide to clean the roof yourself, never, ever use a power washer, even on its lowest setting. Not only is using a power washer pretty much guaranteed to void any roof warranties, it can damage shingles by causing the protective coatingâor even the shingles themselvesâto come off.

Cleaning your roof will require some preparation. Remove any lawn furniture and cover vegetation and landscaping. Overspray is inevitable, and even if the product you use isnât considered toxic, the runoff from your roof can cause plenty of mess on the ground as well.

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Additional Tips And Ideas:

  • If the paint is still wet, simply wash it away with detergent and water.
  • If the paint is not removable, consider painting the tiny splotches with a matching color to help them blend in.
  • Shingles can easily be replaced if necessary, and the fix will be more permanent than painting.
  • Though its desirable to fix the spill immediately, the paint will eventually wear off when exposed to normal weathering.


How An Black Roof Stains Be Removed From Shingles

Shingle Roof – Remove Stains with Soft Washing

The good news is: Yes, Roof Stain removal is possible! Choose between two common roof cleaning solutions used to :do it yourself roof cleaning using a roof cleaning product, or using roof cleaning services from a professional roof cleaning business.

The difference between the roof cleaning company and DIY roof cleaning is cost, and results.

Hire a Roof Cleaning Business

A roof cleaning business has experience at the shingle cleaning techniques and appropriate pressure to use with roof wash products. Pro roof cleaners years of experience will typically result in more complete removal of roof stains.

Do It Yourself Roof Stain Removal

Search for Roof Cleaning Products to find roof cleaner suppliers who offer roof cleaning chemicals, but be careful to know the company and what products they offer. Trust roof cleaner supply companies that offer multiple formulas, and preventive solutions as well. Over the years we have found Roof Cleaner QSE and Roof Shingle Cleaner OX to be quality products with thousands of customers every year.

When you clean your own roof shingles be prepared to set aside an afternoon, and get your ladder out. There is no magic bullet when it comes to Roof Cleaning, and you will at least need a ladder to get up to the level of the gutter. The closer you are to the roof stains, the better your Roof Stain Removal Products will work.

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Cleaning An Asphalt Shingle Roof

  • Protect All Vegetation – Pre Soak and Direct Flow Of Gutters – Before we get started cleaning our roof we want to make sure that all vegetation is completely pre-soaked, with water. This process will insure all cells of the plant are saturated, and when the cells are saturated, the plant will not absorb our chemical through the leaf layer. You still will need to post rinse though, for extra plant protection and insurance.
  • Mix Your Roof Cleaning Chemicals in your garden sprayer. Refer to the mix ratios above. Start with a 50/50 mix for most asphalt shingle roofs, this will insure your chemical is hot enough to actually get a result you would be happy with.
  • Start High On The Roof – Work your way from top to bottom applying and even coat of “roof cleaning chemical.” Some like to toss a 1/4 cup of gain green dish liquid in their mix to allow a slower run of chemicals down the roof. This helps our active ingredient stay wet longer so it has time to work on the algae we are trying to kill.
  • Less Chemical Is More – Less in more in the sense that you shouldnt have chemicals running like a river down your roof. If you are using a garden sprayer, you are not likely to get this type of volume out of your sprayer so you probably don’t need to worry about this portion.
  • Two Common Types Of Algae On Your Roof

    Fire Moss – Fire Moss is less common than the Gloeocapsa Magma below but is still very prevalent on many roof substrates, from cedar shake to asphalt shingles, it loves to latch on and reproduce. When fire moss gets out of hand, it will push up your shingles allowing water to get underneath and severely degrading your roof.

    Gloeocapsa Magma – This is the old “black streak on my roof” culprit. It is most common on Asphalt shingles and can is a spore based algae, it lives on the limestone in your shingles. When it feeds it degrades the limestone and eventually if left untreated, will take over the whole roof making it look all black when that is not the color of the shingle itself, that is in fact the algae growing on the shingle.

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    Technical Reviewers & References

    Catalog Of Types Of Stains On Building Roofs Surfaces Walls

    How To Remove Moss And Algae From Asphalt Roof Shingles ...

    In the following guide we list types of stains by stain color & appearance, by building location or material, and by stain cause. We distinguish among the following stuff that may stain or be found growing building roofs, walls, or other surfaces, with extra focus on asphalt shingle roofs as well as other roofing materials such as wood shingles, wood shakes, roll roofing, and even slate or tile roofs.

    Some of these types of roof stains or discoloration are only cosmetic in nature, while others may indicate growths that are likely to reduce the roof covering life. A more detailed, illustrated version of the list below is given

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    Oil Stains On Asphalt Shingles

    PressurePros said:I’m trying to figure out how heating oil got on the outside/middle of a chimney. They might have some bigger issues going on. Try bleach first at full strength . I doubt that will get it but sometimes bleach surprises me. My next go to chem would be potassium hydroxide as it is both a degreaser and is great at removing soot.

    Question: White Stains On Roof

    Deborah said:

    I have a new roof with architectural shingles that has a white discoloration on it for the moment it was installed. The roofer said it was back surfacing mineral and would wash away. It has been months now. It has faded, but not completely. It is most noticeable when the sun goes behind the house in the afternoon. In the morning, it is barely noticeable. He said it will weather off. Is this true?


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    How To Clean Roof Shingles With Bleach

    Bleach is one of the readily available items that can introduce a new perspective in your roof shingles cleaning routine. When correctly in the right amount, bleach can efficiently destroy the algae, bacteria, mold, mildew, moss, fungus and other organic organisms growing on the roof.

    The reason many homeowners and pro roof cleaners use it is that works fast. However, when not properly used with other solutions, it can be dangerous not only to the roof but also to the surrounding environment. Read on for details of using bleach to clean roof shingles, asphalt, and other types of roof systems.

    How Do I Remove Black Algae From My Roof

    How to Clean Asphalt Shingles with 30 SECONDS Outdoor Cleaner

    Black stainsroofalgae


  • 1 quart bleach
  • 1 gallon water.
  • 1/4 cup TSP or other heavy duty cleaner
  • Herein, how do I get rid of black spots on my roof?

    It’s best to start at the top of the roof and spray down since spraying water up at your shingles can loosen them.

    Cleaning the Roof Yourself

  • 1 cup of trisodium phosphate
  • 1 gallon of bleach.
  • 5 gallons of water.
  • Likewise, will bleach damage asphalt shingles? Chlorine bleach / TSP chemical combination can kill plants, and the phosphates hurt the environment. Chlorine bleach also dries out a shingle roof causing curling, and ultimately shortening asphalt roof shingles life. Roof Cleaner QSE does NOT CONTAIN bleach or chlorine chemicals.

    In this way, how do you clean mold off a roof?

    How to Clean Mold Off a Roof

  • Spray all the plants growing near your house with water, and this will help protect them from any damage caused by the chlorine bleach solution.
  • Mix 1 part bleach to 3 parts water and apply to the mildew-covered area with a hand pump sprayer.
  • Let the solution sit for 15 minutes, then rinse it off with a hose.
  • Does cleaning your roof damage it?

    Roof Cleaning is a Regular Part of Roof CareNeglecting your roof can lead to creeping damage that may be expensive to repair and could cause loss of personal property from intrusion of water and mold. Doing at least an annual cleaning and inspection will go a long way to prevent long-term issues with your roof.

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    Preventing Black Streaks On Your Roof

    Can you permanently get rid of algae? The short answer is âno.â Roof algae is similar to having a cold. Like many cold viruses, algae spores are airborne and unavoidable. You can treat the symptoms, but eventually you will have another algae problem, especially if those around you have it on their roofs as well.

    But donât despair! Like washing your hands frequently and eating healthy to prevent catching a cold, cleaning and maintaining your roof can help prevent black streaks on your roof from returning. Here are some ways to keep roof algae at bay:

    Maintain Your Roof

    Trim tree branches to allow more sunlight to reach the roof and minimize the accumulation of debris. Debris that does begin to accumulate on the roof should be cleared regularly by hand as part of a regular maintenance program. This will provide an environment less inviting the growth of roof algae.

    You should also keep gutters and downspouts clean and free of clogs to promote proper water drainage. Never allow gutters or downspouts from an upper roof to drain directly on a lower roof extend the downspout from the upper roof into the lower gutter.

    Gutters draining onto a lower roof not only promote algae growth but can cause water to pool on your roof, which can damage shingles as well as the underlying wood structure.

    Install a Copper or Zinc Strip Along the Side of the Roof

    Get New Shingles


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