Algae & Moss Prevention And Cleaning For Asphalt Roofing Systems
To understand how to deal with the recurring problem of algae and moss growth on rooftops, it is important to learn what they are and how they grow and spread. Although some similarities exist, algae and moss are very different and require slightly different procedures to prevent or to remove.
Often mistaken as mold or mildew, the black discoloration and streaks visible on many roofs across the United States and Canada are actually algae. The algae can form w here moisture tends to dwell on roof surfaces. Coastal or humid climates create the most conducive conditions for algae growth. The most common type, gloeocapsa magma or blue green algae, protects itself from damaging ultraviolet rays by producing a dark pigmented sheath. The algae discoloration typically begins as small spots then quickly transforms into streaks on the roof plane. By the time the algae is visible, it likely has been present for several months or longer.
Moss is a non-vascular plant that obtains water through its leaves, unlike most plants that gather water through its root system. Moss must therefore have a moist environment to survive. In North America, moss tends to grow on north facing roof planes that receive less direct sunlight and stay damp longer than south facing planes. Overhanging tree branches provide additional shade and drop debris on the roof that further holds in moisture and acts as a food source for moss.
Should You Be Worried About Moss On Your Roof
Moss might give your home a touch of fairytale charm, but it can be an indicator of water damage or other roofing problems not what you need when youre looking to live happily ever after.
So what should you do if your roof becomes covered in moss, lichen, algae, or similar growths? Do you need to replace your roof entirely, or is there an easy way to safely remove the moss and restore your roof back to its previous state? Keep reading to find out.
What To Avoid When Removing Moss From A Roof
There is a lot of bad advice when it comes to cleaning moss from roofs. The main concern about these methods is not that they dont clean the shingles properly, but they damage them as well. Using the incorrect method of cleaning could also void the limited warranty of the roof. It is always best to consult with a professional if you arent sure how to go about cleaning or repairing your roof.
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Install Zinc Or Copper Strips
Preventing moss from the start is the best way to avoid dealing with its consequences. Many homeowners attest to the effectiveness of zinc strips. When it rains, water rolls over the metal and washes the roof, killing moss in its path. These strips inhibit moss from growing back. Theyre also great at preventing the appearance of black stains.
In a few years, the strips lose their effectiveness so youll need to buy and install new ones. Copper strips also make good alternatives and can last longer than zinc.
Premade strips are simpler to install and also look cleaner on your roof. You can purchase these strips online or at a home improvement store.
How To: Roof Cleaning For Algae And Moss
Do you have moss or algae growing on the roof of your home?
If you answered yes to this question, you may be wondering what causes algae or moss growth, what you can do to avoid it and the roof cleaning process.
Algae and moss can grow on your roof because it could be providing a good environment for it. Thats because conditions like shade, moisture, and humidity are a perfect breeding ground for algae and moss.
Sure, cutting back trees hanging over your roof can eliminate some shade, but what is an effective way for you to clean up algae and moss on your roof that is already growing there?
Read on to learn how to complete roof cleaning for algae and moss.
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How To Remove Moss From A Roof: Everything You Need To Know
While moss can cause some roofs to look more appealing, it can cause serious damage to a roof if you leave it untouched. While the initial phases of a moss infestation aren’t too noticeable, as it grows and becomes intertwined with your shingles it can become more difficult to remove. Moss can soak up the water around it and cause water damage to your shingles, which can then eventually make its way into your home. If you’re trying to figure out how to clean moss off a roof, here are some things you need to know and simple steps to follow.
Moss is a type of plant that looks like a furry green patch and tends to grow in humid locations with shade. There are many different types of moss, in fact, there are over 16,000 types distributed across the world. On roofs, moss tends to grow on asphalt shingles and wood shingles. Some species of moss will only grow on specific roof shingles like wood, and others will grow on different parts of the shingles. If your roof has a moss infestation, chances are there is more than one type of moss growing on it.
How To Remove Moss From A Roof Naturally
Your roof is designed to protect your home and your family from the elements. Heat, cold, sun, and storms all take their toll. Eventually, you may notice green clumps growing in shady places across your roof. These unsightly splotches are very likely moss.
Moss is more than just an unattractive nuisance. Over time, It can cause damage to your roof. Moss absorbs water and keeps the roofing underneath it damp. On sloped roofs, moss can intercept water draining down your shingles. If you have asphalt shingles, the moss can cause the edges to lift, which makes them more vulnerable to blowing off in high winds. It is important to know how to remove moss from a roof safely if you do find roof moss.
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Hose Off And Scrub The Area
Spray washing the moss off your roof is the easiest method to get rid of it. You can prepare a mixture thats composed of 50 percent water and 50 percent bleach. Make sure to spray in a downward direction.
Leave the solution on your roofing shingles for up to 20 minutes. This allows enough time to kill moss. As long as youve covered nearby plants, you wouldnt need to worry about killing them as well.
Using a long-handled brush with soft bristles, youll be able to manually remove the moss. Again, do this using a downward motion to prevent damaging the shingles.
Never forget the last step which is to wash off your roof with plain water. Some homeowners who use commercial roof cleaning products choose to leave them on.
How Do Zinc Or Copper Strips Work
They are fitted at the top of the roof, and when it rains, the rain absorbs metal particles from the metal strip and carries them down over the moss as the rain runs down the roof. The metal particles poison the moss, algae and other plant life growing on your roof, and so the moss will wither and die over time, falling off your roof. It will also mean that new moss and algae will not grow due to the poisonous particles that are deposited over your roof from the zinc strips.
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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.
Tips For Installing Zinc Or Copper Strips
When installing the metal strip its crucial that you do not use nails to hold it in place this will cause leakage when rain drips down along the nail and through the roof structure. Its also essential to ensure the zinc or copper strips are lying thin and as close to the roof as possible, to prevent warping. When warping occurs, the area of the roof beneath it does not get treated by the strips because instead of running directly down the roof, it runs along the strip to a less warped area.
Whichever method you choose, its important to look at other factors that cause moss growth and try to remove these. For example, trimming overhanging trees and bushes will remove shade which moss needs to grow, and moving any satellite dishes to areas that wont create shade. The more sunlight your roof is exposed to, the less shade and moisture will be present, so the less likely moss is going to grow.
Dont forget, for any roofing queries, questions or products our experts are here to help just give us a call on 01752 692 760.
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Never Use A Pressure Washer
The worst way to remove moss is to use a pressure washer this will remove moss from your roof without a doubt, but it is the fastest way to cause damage to your roof shingles as the force can break them, increase weaknesses and strip the surface granules from your tiles. Additionally, if there are any weaknesses or leaks the pressure washer can cause flooding to the loft space.
How Do I Clean Moss Off My Roof
If you notice moss in small sections, you should remove it. You can try to do this on your own, however, most homeowners are more comfortable hiring a professional to handle the job.
If you decide to tackle the task on your own, avoid using a power washer. Most people dont have the knowledge or skill to prevent the spray from finding its way under the shingles. If you inadvertently force water beneath your roofs shingles, you could end up doing far more harm than good.
A safer way is to use a mix of 50-50 water and household bleach to kill the moss. The Asphalt Roofing Manufacturers Association recommends letting the mixture sit for 15-20 minutes and then rinsing it with low water pressure. As it dies, the moss will loosen, and itll be easier to rinse or brush away.
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How Moss Ruins A Roof
In general, it is north-facing roof areas that receive little sunlight that are prone to mossespecially when the overall climate is cool and damp. But even in damp climates, roof areas that receive even a little strong sunlight each day may not develop moss. You are most likely to find it on areas of the roof that are shady nearly all the time, such as roof areas beneath heavy tree canopies
Roof moss begins with a thin dusting of green that you may notice only from low angles. This thin layer on the top of the shingles gradually expands and becomes wide, thick, and mat-like. The seams between the shingles and the shingles’ edges also develop moss because they tend to be especially shaded.
As moss thickens, it works its way under the shingles and raises them up. If the shingles are wood, this process can happen at an alarming ratewood’s porous surface is prime real estate for moss growth. Once moss has adhered to wood shingles, it is much harder to remove than from the relatively smoother planes of composite or asphalt shingles.
Once the moss is a thick mat, it becomes a sponge that soaks up and retains all moisture. This stored water quickly works its way under and between shingles and then onto the lower levels of roofing felt and the structural elements of the roof. This eventually leads to rot, and rot leads to further decay of roofing materials. The accelerating cycle can even destroy a roof in a matter of a few months.
Can Roof Moss Be Composted
Moss is a non-vascular plant and survives as long as it has access to moisture. Because of this, it decomposes much slower than most materials and can take several years to break down completely. You can speed up the process by layering moss with grass clippings, but it will still take months or years.
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What If The Moss Appears Dead
If the weather has been consistently dry, moss may appear to be dead. However, some species of moss can stay alive when dried out for months. All it will take is one rain for it to recover and continue growing. If your moss has dried out, take the opportunity to have a roofer remove the moss from the roof.
Moss Is Not A Huge Problemunless You Ignore It
If you find moss on your roof, dont panic. Moss thrives in damp, moist areas, including roofs that are north-facing or shaded by trees.
A simple mixture of bleach and water will kill the moss, causing it to dry up, release from your roof, and blow off in the wind.
If you ignore it, overtime moss will grow beneath your shingles and lead to more severe damage.
Now that you know why moss grows on roofs, how to remove it, and how to prevent it, its time to get to work! If you have any tips, techniques, or products that work well against moss, leave a comment and let us know!
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Does A Roof With Moss Need To Be Replaced
If you notice moss or algae on your roof, dont panic. The presence of moss doesnt always mean youre destined for a whole new roof, nor does it mean your home has suffered water or moisture damage.
Moss tends to form in areas where it is shielded from the sun. If sections of your roof are under heavy tree cover, these are prime spots for moss to thrive. And if you live in a damp climate that sees a lot of rain, chances are you will notice telltale signs of algae or moss forming on your roof at some point in your homes lifespan.
The presence of moss doesnt always mean that your roof has sustained damage, especially if you catch it early. Like leaves in your gutters, moss is only a problem if you allow it to grow unchecked.
Difference Between Moss And Algae
Though they might be grouped as the same thing because they grow in the same area of your home, moss and algae are actually quite different and distinct.
Moss always appears more green and fluffy-looking than algae, though it might appear browner during dryer seasons. Moss will also grow up off the roof, while algae will grow flush to the shingles and fixtures, staying flat and unobtrusive. Algae will appear in many different colors such as gray, blue, green, or brown.
A small amount of moss is relatively harmless, but left unattended, it can grow and eventually damage your asphalt shingles. Moss should be removed. Algae actually fosters the growth of mold, which can lead to very serious issues. Algae, too, should be removed quickly and efficiently.
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Choose The Right Day And Prepare The Area
Check the weather forecast and choose a cool or overcast day with little to no wind so the spray hits your shingles, not the neighbors. Those conditions allow the cleaning solution to soak deep into the algae colonies without evaporating too quickly.
Next, repair any loose shingles or flashings, and clean the gutters and downspouts so they can drain freely.
Then prepare the area by moving lawn furniture and covering vegetation, because youre going to have overspray. Even though the product we chose isnt toxic, the runoff can be pretty ugly. So a little prep work will save you cleanup time later.
How To Remove Moss From Roof Tiles
Does your roof look far too green for your liking? Use the following methods, tools, and materials to eradicate moss from your roof.
The only greenery you should be able to see near your rooftop is the leaves growing off branches from surrounding trees. If you have moss growing on your roof, then its time to do something about it.
If you have moss growing on your roof, theres a high chance you have a north facing roof. A north facing roof usually has little sunlight, which enables moss to buildup on the roof. Moss can grow quite quickly, and it will grow in between roof tiles, filling in the voids and lifting up roof tiles and slates.
Moss growing under roof slate and tiles can push the slate out of position allowing rainwater to seep into the roof structure. When rain finds its way into the roofing structure thats when decay and rot sets in.
If you want to clean moss off a roof yourself, you will have to plan how you are going to kill the moss and remove it effectively. You will need to treat the roof to stop the moss from growing back.
Its recommended anyone cleaning moss off a roof should do it on a cloudy day. When applying roof cleaning products onto a roof on a hot sunny day, it will quickly evaporate, and you wont get the desired result.
Most roof cleaning products require at least 20 minutes for it to absorb into the moss. However, there is more than one way to remove moss from your roof tiles.
Roof Moss Treatments
How to Clean Moss from the Roof
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