Moss can damage the roof. It will damage three-tab composition shingles, cedar shingles, or cedar shakes without discriminating. It should not be allowed to take hold there. Tim Carter, Nationally Syndicated Newspaper Columnist, Ask the Builder® has this to say, "Moss is of great concern to me as it absolutely can shorten the life span of untreated wood and asphalt roofing materials." Click the photo to the right to see how.
Dicranoweisia cirrata a.k.a. Pin Cushion
How is moss harmful to my roof?
"Moss holds itself to its substrate using root-like structures called rhizoids. Roofing professionals say that these structures grow into tiny cracks in the roofing materials, accelerating their degradation, and eventually causing leaks. The moss may also hold moisture on the roof, allowing decay-causing organisms to get a foothold. Moss could grow under the edges of shingles, loosening them, and causing leaks in that way...." Quoted from a document published by Oregon State University, Botany 465 - Spring, 2000.
Why does moss return year after year?
If you take the time and do the research, you will find that simply killing the moss is not enough. A paper published by the Oregon State University says, "If you try to control mosses, but do not address the underlying conditions that favor moss growth, they will surely return."
I've got a new roof. Do I need moss control?
Yes! Under the right conditions, without a regular maintenance plan, you can expect to see moss on your roof within 3 years of its being newly installed.
Are conditions right on your roof? Just take a look around your house. Are there trees nearby? Is a portion of your roof shaded well into the day? Do your neighbors have moss? Do you depend on the wind and rain to keep your roof clean? If any of these conditions match yours then you can expect moss.
Is there anything that will keep moss away?
Yes! Dave's Moss Away can keep moss away. With regular use of my gentle cleaning system, moss will not get a grip on your roof.
Make it your goal to never have roof moss. Let Dave's Moss Away help you to keep moss away.
How often should my roof be cleaned?
A report published by Clean Water Services of Oregon, entitled "Safe Roof Moss Control" states, "cleaning roofs once or twice a year is recommended." Cleaning removes the debris that slow drying of the roof (leaves, needles, etc.) and removes moss.
Do I have to cut back trees that are shading my roof?
Trees can be both practical and ornamental around the home, but if your tree is fostering wet conditions on your roof, then pruning is in order.