Dangers of Moss

By: Kyle Olivarez

As we all know, the Pacific Northwest is a beautiful place to live. Within roughly an hour we can be doing just about any outdoors activity, enjoying the many different types of scenery and the breathtaking views this magnificent part of the world offers. It is a place where life flourishes and growth is well supported.  However, despite the beauties of this part of the country there are some things that we should be aware of, especially as home and property owners. Today, I would like to focus on the effects of moss, particularly how it can be damaging to a rooftop, and how to 1) kill and remove moss and 2) how to prevent moss from growing on your roof.

Moss is one of those small types of plants that tend to particularly flourish and grow, sometimes rather quickly, here where we live. Moss spores are constantly spread by wind and other types of weathering, and these spores fall in a constant rain on exposed surfaces; those surfaces which are hospitable to a certain species of moss will typically be colonized by that moss within a few years of exposure to wind and rain. Materials which are porous and moisture retentive, such as brick, wood, and certain coarse concrete mixtures are hospitable to moss. The roof tops of our homes (as depicted below) are especially susceptible to this occurrence, and over time can have very damaging effects on the integrity, safety, and value of our homes.


As shown, a rooftop (of any kind whether it be composition, wood shake, etc) originally free of any debris or moss can look like this is just a few short years, with very damaging effects. As moss grows, it can begin to lift shingles and with extended time begin to rot and deteriorate roofing. With much extended exposure, the materials underneath roofing will begin to deteriorate and rot as well. As this happens a rooftop can develop ‘sags’ or large ‘soft spots’ due to the deterioration caused by the moss. Another effect that occurs is strong discoloration of the roof. Some of these effects are depicted below.


Margaret’s has been effectively killing, removing, and keeping our customers rooftops free of moss since 1986. Our process is simple, effective, and will not damage the integrity or appearance of a rooftop. We start by first laying a product called Zinc Sulfate over the peaks of a roof as shown.


Zinc Sulfate is an environmentally safe product we have been using for years now. It has proven effective at killing moss on a roof and preventing any growth on a rooftop for upwards of a year. After we lay an initial mosskill application, we allow 2-4 weeks for weathering to spread it over the roof and kill any moss there. Once that time has elapsed a crew of 2-5 employees, depending on the size of the roof, will come and scrub the moss off. Once all the moss has been scrubbed we blow all debris off the roof and clean any debris that falls into the gutters, leaving the roof looking clean and new. We then apply a second mosskill application, and most have since had us out each year to do a mosskill application to prevent moss from growing on their rooftop again.

Our process is effective and safe. Moss can drastically reduce the lifetime of a rooftop, so I would thus encourage anyone with moss to have it removed and then maintained each year through a simple mosskill application. If you don’t have moss yet, why wait for it grow to start protecting your roof? Start now with a our simple mosskill application, thus allowing your roof it’s full life span, and a sizable savings in your pocketbook in avoiding having to have your roof scrubbed.

Again, we live in a beautiful part of the world. Let’s do all we can to make sure our homes as well look clean and beautiful, and avoid the stress of having to deal with extensive roof repairs or in some cases all out roof replacements. Let’s do the small and simple things to avoid those stresses, and I would encourage to do so not just with the maintenance of our homes, but I am sure in many ways there are small and simple things we can do that would cut stress and worry down in many aspects of our lives. As we do so, we will alleviate ourselves of unnecessary stress and worry, and free ourselves (and our pocketbooks) to allow us to enjoy more and more of what this beautiful part of the world has to offer.

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Phone: 360.366.0591
Fax: 360.393.4096

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Tuesday 8am - 4pm
Wednesday 8am - 4pm
Thursday 8am - 4pm
Friday 8am - 12pm
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Sunday Closed

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