A roof in need of moss removal

How Different Moss Types Can Affect Roof Cleaning

It’s green, kind of furry, and likes to grow in the Portland area. “What else do I really need to know about moss?” you might ask yourself.

Believe it or not, there are numerous types of moss.  Plus, there is a chance that what you see on your roof, pavement or deck might not even be moss. Algae, lichen and liverwort also are common organisms and plants in cool, damp environments. Commonly we just see something green in a place it shouldn’t be and call it “moss.” Don’t worry, we know what you are referring to. Fortunately, the same methods and treatments used to control these are the same as for moss.

On decks and pavement, the primary concerns with moss infestations, other than aesthetics, are personal safety and damaging moisture retention. Moss can be very slippery when wet and can pose a serious slip and fall risk. Additionally, moss helps keep moisture in surfaces that need to dry out in order to avoid either rot or over expansion.

With roofs however, the results can often be the most damaging, at least in terms of property damage. Moss prevents rainwater from promptly flowing down the roof as designed. It creates “mini-dams” that slow the water flow and increase the chance of it back flowing to where it was not intended to go. While all mosses do not have roots, they have a rhizoid which act as roots, anchoring to them the roof. With composition roofs, this results in an acceleration of granule loss. With cedar shake roofs, the moss helps accelerate the rotting of the cedar from the moisture retention. This is why roof cleaning is such an important function in the Pacific Northwest.

There is a direct correlation between how well a roof is maintained and how soon roof replacement is necessary.

So it reasons that is not all moss is the same, then a single approach to eradicating the moss will not be sufficient.   Some moss types grow in clumps while others tend to grow as a broad spreading “sheet” across a surface. It is not uncommon at all to some times have more than on type of moss on a roof. Using a professional roof cleaner (or pavement and deck cleaner) who is aware of different mosses and removal methodologies is the first step towards properly addressing the problem.

Please give us a call if you would like a review of your moss problem.

Tags: deck cleaning, deck maintenance, moss, moss removal, pavement cleaning, Roof Cleaning, roof maintainence, roof maintenance, roof moss