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Killing The Moss That Damages Your Roof

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If you complete visual roof inspections and live in a wet area, then you might see any number of growths or formations on your roof shingles. While you may think that moss and mold look the same and require the same sort of removal practices, this is not the case. Keep reading to understand moss growths, how they can cause damage, and how you can remove the moss.

Why Is Moss Damaging To The Roof?

Moss is one of the many types of growths you may see on your roof, and it develops in shaded areas or north facing spaces. Moss is unique in its structure and is not a type of fungi, like many people believe. Moss is actually a type of plant called a bryophyte. When it comes to moss, there are about 10,000 individual species.

Mosses are unique in their structure, and very different from algae, mold, and other types of fungi. One of their defining characteristics is the presence of rhizoids, or root structures that sit on the bottom of the moss and allow for subterranean penetration so that fluid and nutrients can be pulled from the soil. Across the top of the moss sits the cells that are responsible for photosynthesis. 

Since moss has the root structures, they can cause a great deal of damage in the way of roof penetration. Specifically, the roots will grow towards the dampest and wettest areas of the roof. As the rhizoids grow outward, they penetrate roofing shingles and also the wood decking material. Not only does the moss spread in way that is damaging, but the moss itself will act as a sponge and absorb a great deal of fluid. Moss always remains wet, since this is necessary for growth. This water will remain in direct contact with the roof and can lead to the degradation of your shingles. 

You may notice that moss will stop spreading and growing during the coldest months of the year. However, the plant will not die. It will simply remain dormant until conditions are ideal for growth. 

How Can Moss Be Removed?

Since moss is a unique plant, it requires removal that is unique to its structure. Moss will become dormant when it is in a dry environment. This means that removing moisture will not kill the moss, but it is the first step in completely eradicating moss formations from your roof. Make sure that tree branches are completely cut back and that gutters are working as intended. Also, ventilation in your attic can remove the moisture that may be moving through the deck and into your shingles. 

Once the moisture issue is controlled, you need to spread a compound on the moss that will kill it. This will release the root growths from the roof and the moss can be easily swept off the roof. You can use bleach, ammonia, vinegar, or dish soap. All of these things will cause the cells within the moss to burst and the plant will die. However, a more powerful product with a metal like zinc or copper will be toxic to the moss and will cause it to die much more quickly and permanently. Also, some of these products absolutely shouldn't be used together, such as bleach and ammonia, since they create noxious gasses when mixed.

Also, metal solutions will often require only a single application while DIY mixtures require several applications in most cases. Copper is more toxic to the moss, so it is a good choice, but it is also expensive. This is why many people choose a zinc alternative. You can buy premade moss killing solutions at your local home store. These solutions can be snapped onto your hose and a mix of the metal and water will spray out onto your shingles. 

Once you spray the moss, wait several days for the miss to die and either sweep the roof or use your hose to release it with a spray of water. If your roof needs to be replaces because of any moss damage, reach out to a professional at a place like A&W Custom Carpentry and Roofing.


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