Problems With Using Bleach On Asphalt Roofs
There is some concern regarding the use of chlorine-based productson asphalt roofs. Household bleach can damage asphaltdue to its high sodium content. Apparently, the sodium causes anelectrochemical reaction that reduces the elasticity of the asphalt leading to stiffness, brittleness and curling of the shingles.
When Should I Treat My Roof For Moss
If youre looking to prevent moss, then your roof should be cleaned by professionals about once a year. If a problem is developing, this can help catch it early on. Also, use the steps in our previously section called How to Prevent Moss from Growing on Your Roof.
If youre looking to remove moss, its best to remove it as early as possible so that it doesnt grow and cause more significant damage to your roof. Treating it before fall rains is an excellent time of the year because thats when its growth will start to kick into high gear.
Check For Cleanliness And Rinse:
Allow the solution to soak into the shingles for at least 15 minutes. If they are severely molded, then leave the mixture for little longer. Next, rinse the shingles thoroughly with a garden pipe. Start from top and rinse downward to prevent water seepage. Move your gloved hands over the shingles to check for any mold remaining after youve finished rinsing. If there are molds still present in shingles, add the cleanser again, wait for 10-15 minutes and repeat the rinse process.
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How To Identify Youve Got A Mold Problem On Your Roof
Microbial overgrowth from algae, moss, mildew, and mold are common in homes located where there is high humidity, or insufficient roof drainage.
Unfortunately most homeowners mistakenly characterize the signs of a mold problem as a cosmetic issue or one of old age.
Heres what you should look for when looking for mold on roof:
Benefits Of Hiring A Roofing Contractor

Mold is typically the result of algae growth. Mold spores can easily become airborne, jumping from roof to roof. That is why you may see a mold problem in a certain neighborhood. Certain conditions are more favorable for mold, such as roofs with leaks or wood rot. Oftentimes, the presence of mold is a sign that there other roofing problems exist. While you may not visibly see roof damage, that does not mean that damage does not exist. When you call in an experienced roofing contractor, underlying roof problems may be found. Making these repairs can reduce the likelihood of mold growth in the future.
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Sanding Wood Surfaces To Clean Mold
We often see remediators attempting to clean up mold by sanding surfaces, by hand or by power sander.
Sanding wood surfaces to remove mold is physically possible for smooth surfaces but in our opinion this is a slow,labor intensive procedure which is impractical for any large area cleanup. Spray processes are significantly fasterand more thorough.
Sanding wood building surfaces by hand is
Clean the surface mold, dry the building, and if you like, use a sealant as discussed below.
The fungal material left inside of wood framing or sheathing and which forms visible stains is not going to affect building occupants provided the building is kept properly dry and free of leaks.
Even if you removed all of the stain by deep sanding, future building leaks will still \ produce new mold growth, so sanding is in most cases a wasted effort.
An exception we make to this general advice is where exposed beams are cleaned or sanded for cosmetic reasons. Still in that casemedia blasting cleans better and faster.
How Mold On Plywood In Attic Spreads
Mold spores in general spread very rapidly and the presence of a moisture problem in your attic will only accelerate their growth potential. Mold that has colonized on attic sheathing will continue to grow and spread if left unchecked.
Mold spores can also end up being distributed throughout the rest of your home if you have an HVAC system in your attic. The HVAC system can pick up mold spores and then blow them throughout your whole house. Leaving the rest of your home susceptible to mold too.
Not only will mold spores have the ability to begin growing throughout the rest of your home, but the spores have the potential to make you and your family very ill.
Mold can be toxic and hazardous to your health. Mold exposure tends to cause respiratory problems in people, especially those with a weakened immune system or a pre-existing health condition.
We are all constantly coming into contact with mold spores in our everyday life. In fact, mold in its natural element outdoors actually plays a very crucial role in our ecosystem. Mold aids in the breaking down of old leaves, plants and wood.
Mold reactions are most severe when it has the ability to colonize and grow inside our homes where we live and breathe the air in on a regular basis.
Not everyone who comes into contact with mold will suffer side effects, but many do. Exposure to extreme mold infestations can cause serious, life threatening side effects in people so it is important to avoid this at all costs.
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Kill Existing Moss With A Cleaning Solution
Before you can prevent more from growing, youll have to kill and remove any existing moss with the help of a cleaning solution. In the aforementioned section titled How to Remove Moss From Shingles on a Roof, we discussed different types of cleaning solution you can use, how to make your own mixture, how long to let the cleaner sit on the house, and how to clean it off. These steps will help you remove it from your roof so that you can move on to the prevention methods.
If none is currently on your home, you can skip this step and move on to number two.
I Just Had A Roof Replaced On My House New Osb Sheathing And Added On Deck Intake Vents For Ventilation Along With Ridge Cap Vents Has Not Been A Month And Went Into The Attic And Noticed Almost All New Osb Has White Fuzzy Mold Growth Roofing Company Is Supposed To Come Out Next Week To See Whats Going On
The amount of regrowth is high for only a month. Is there any chance the OSB was saturated during the reroof? I.e. was it rained on prior to install? This certainly would explain the regrowth in an otherwise dry attic. Also, I see signs of past growth on the adjacent framing. This indicates a long term moisture issue in the past.
Here are a few items I recommend investigating:
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Easily Clean Mold Off Roof Without Any Scrubbing
Wet And Forget is as simple as spraying your outdoor surface and leaving it. Green algae, black mold, and moss begin to die off on contact. The combination of the wind and the rain rinses and scrubs your surfaces clean over time. Green stains clean up in 1-2 weeks, black stains and moss clean up in 2 or more months. Wet the surface and forget it, there’s no rinsing or scrubbing! Life’s Dirty. Clean Easy.
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Why Do Algae And Moss Grow On Asphalt Shingles
The wind and small animals will carry algae spores, and its one of the reasons why you may see algae-covered roofs clustered in a single neighborhood. Moss, on the other hand, likes moist, shady environments and often grows on the north-facing side of trees. Overhanging tree branches and debris left to accumulate on a roof is why you may find clumps of this green stuff gathering on asphalt shingles.
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Is It Necessary To Remove Moss From A Roof
Yes, it is necessary to remove any moss thats growing on your roof. While a little bit can be harmless, its important to remember that its a living thing and will eventually grow, which can cause significant damage to your home. So, if you notice any on your roof, its best to remove it as soon as possible, whether youre planning to do it yourself or hire a team of professionals to do it for you. Getting rid of it now will help prevent future problems down the line. Youll be glad you did.
Why Leave It To The Professionals

You might be thinking, how hard is it to spray some bleach and rinse it off. We would caution that this work is not as easy as it looks.
First, while mold can easily be removed from newer shingles in good condition, it is not so easy to remove from older, deteriorating shingles. We will inspect the roof before doing any work to see the condition of the roof.
Second, unless you are a roofing professional, you could potentially do more damage than good. One misplaced step or keeping the bleaching agent on too long, and you might be paying for replacing your roof.
Finally, unless you get on roofs for a living, trying to do the work yourself is potentially dangerous. Let the professionals do the work and stay safe.
If you want someone to come out to remove mold from your roof, call on the experts here at Janney Roofing. We are licensed roofing contractors who have been in the business for many years. We carry all the needed roofing supplies to handle your roofing needs. Whether you have an asphalt or metal roofing, give us a call today.
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Diy Algae And Moss Removal Recipes
Luckily both algae and moss can be easily removed from shingle roofs. DIY stores sell many popular liquid solutions that are specifically made to kill the moss. Or you can make your own moss remover in a large spray bottle with one of these four DIY recipes:
- 240 ml dish washing soap + 7,5 liter of water
- 450 grams powdered oxygen bleach + 7,5 liter of water
- 500 ml chlorine bleach + 7,5 liter of water
- 500 ml white distilled vinegar + 7,5 liter of water
When using one of these homemade options, you should wet down the roof with plain water first, then apply the cleanser and let it rest for 20 to 45 minutes. Lightly scrub your roof with a soft-bristle brush, and then rinse with water.
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What Does The Mold Growth Typically Look Like
Mold growth on the sheathing occurs in either a flat, low profile configuration or a fuzzy, 3 dimensional pattern. The flat, low profile growth can often look like soot or staining. In fact occasionally a home inspector will misidentify the mold growth as soot from a fire. Notice the dark staining in the first picture. This type of mold growth will not smudge or wipe off. The dark discoloration will remain long after the mold has stopped growing.
Below is an image of heavy 3-dimensional mold growth on the sheathing. Beneath the fuzzy growth, areas of staining can be observed as well. This type of attic mold is less common and typically easier to remediate. Because the staining is limited, a thinner layer of encapsulant can be applied.
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How To Prevent Black Streaks On Roof
If youve already removed the algae from your roof once and you want to make sure you dont get it again, or if youre building a new house and you want to make sure that your roof doesnt get those black streaks from algae, there are 2 things you can do to prevent the algae from forming:
#1 Look for algae-resistant roof shingles which have either copper or zinc added to prevent the algae from forming.
Heres how AR roof shingles work:
If exposed to sunlight, the ultraviolet rays will readily break down asphalt shingles. Thats why the shingles you see are covered with the small colored ceramic granules. These create a powerful sunscreen and offer you different colors to match your exterior decorating scheme. Many shingle manufacturers make shingles that have special colored granules that contain copper. These help to prevent the ugly black roof-algae stains you might see on your existing roof or that of a neighbor.
How To Remove Mold On A Roof
If youve ever driven around your neighborhood, youve probably spotted roofs that are streaked black with discoloration, stained, or even tinted green. Mold, algae, moss, and mildew thrive atop roofs, especially on patches of roofs that are shaded from the harsh UV light of the sun. So no, these are not signs that your roof is falling apart, just an indication that its the perfect environment to allow this type of growth to flourish.
Mold, mildew, moss, and whatever is growing on your roof is unsightly and possibly damaging. Allowing this growth to remain can damage your shingles, and if your shingles cant do their job, you could see a future of water damage and costly repairs. Getting rid of this pesky problem doesnt have to be an expensive, time-consuming chore. It just takes a few household cleaners, some roof safety equipment, and access to water.
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Make And Apply The Bleach:
Put on rubber gloves and also wear breathing mask before you start the procedure. By doing this, you can protect your skin and lungs from the fumes produced by bleach. In two-gallon bucket, create a cleanser composed of ¼ bleach and ¾ water. Then, add one tablespoon of trisodium phosphate and mix well. Fill the mixture in spray bottle and apply it on the molds.
Safety Measures For Mold Removal
We cant stress enough the fact that you NEED to wear protective gear when in close proximity to mold. This means even if youre just doing a visual inspection of your attic, wear gloves, a face mask, and keep your body fully covered. Any disturbing of mold will release spores into the area, and you dont want to breathe them in trust us.
There you have it how to remove ceiling mold after a roof leak. Take our advice above into consideration when dealing with ceiling mold, and remember to always gear up when disturbing any mold spores. If have a roof leak and need to get it fixed, Element Roofing offers roof leak repair and roofing in Livermore and roofing in Hayward services.
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What If I Like The Moss
Some homeowners find moss enchanting, like ivy growing up the side of their home. If youd like to grow moss or other plants on your roof, you could consider investing in a residential green roof. Thin, extensive green roofs are enough to grow succulents and mosses. If youre interested in taller plants, consider an intensive green roof.
How Do I Remove Roof Mold

Removing roof mold from a house is not only important in the prevention of a number of serious health conditions, but also gives an overall better look to the house. While there are a number of ways to remove roof mold, some of the best include using chlorine bleach solutions and copper sulfate solutions. In addition, preventing the growth of roof mold to begin with will eliminate the need to get rid of it.
One of the best ways to remove roof mold is to use a chlorine bleach solution. To do this, start by mixing a solution that combines one part bleach with three parts water. Pour the mixture into a hand sprayer, similar to that used for spraying starch onto clothing. Be aware that while this application process can be time-consuming, it is essential to ensure complete saturation. Allow the chlorine bleach solution to remain on the roof for between ten to fifteen minutes, and then rinse with warm water from a garden hose. Finally, examine the roof for remaining mold. If any mold still exists, repeat the process, being sure to rinse the roof after each application of chlorine bleach.
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Reader Question: How Should We Clean Moldy Wood Framing In Our New Home
We are building a new home, the wood framing has mold, the walls are still open. How should the builder clean or remove the mold? – Linda Lewis 4/7/2013
Reply:
Thanks for the question Linda.
If the mold is ONLY the cosmetic black mold that we describe
at BLACK COSMETIC MOLD then it really is only cosmetic and could be left in place.
There are two difficulties with this:
- First you may have trouble recognizing the cosmetic mold I describe in that article, though sometimes the growth patterns make it clear. To address this you could spend roughly $50. to send a representative tape sample of the mold to a mold test lab for confirmation.
- Second, while the black mold I describe is indeed harmless on framing lumber and virtually always came in on the lumber from the lumber yard, also one wants toWatch out: in some cases, particularly on lumber that has been wet, or on treated lumber, my own field and lab tests have found Aspergillus sp. and Penicillium sp. growing among the harmless black mold.
So we might want to clean the lumber.
I tend to stay away from labor intensive approaches and from incomplete approaches . Keep us posted and send along some photos if you can as what you learn may help others.
This article series includes advice on cleaning mold found on surfaces of un-finished wooden building materials such as framing lumber , and building roof, wall, and floor sheathing such as plywood, tongue-and groove pine boards, and other structural wood surfaces in buildings.