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Roof Wash

After treating the roof, mother nature will take care of the rest over the next several months.

What is a roof wash and why is it needed?

In the Pacific Northwest, we can guarantee you will have some sort of organic growth on your roof, whether you have asphalt shingles, tile, wood shingles, or a tin roof, can be problematic. Most homes here in Oregon have asphalt shingles and moss growth causes moisture retention and lifting of shingles. In fact, some insurance companies and home inspectors are now mandating that homeowners have roof moss removed or their insurance policy will be terminated or the home will not pass inspection.

Some inexperienced companies believe moss can be scraped or brushed off of an asphalt roof. The various shingle manufacturers have mandated a very specific process to kill the moss without using any physical agitation.   The moss will simply decompose and fall away from the shingles without causing any granule loss.

In the Willamette Valley, it is important 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.

As stated from the Asphalt Roofing Manufactures Association (ARMA),

“Moss spores may also be carried by wind or animals and can easily spread throughout neighborhoods. Unlike algae, moss can be detrimental to asphalt shingle performance. Moss can cause the leading edges of the shingles to lift or curl, which increases the risk of shingle blow-off during wind events. In severe cases, moss build-up can cause lateral water movement resulting in moisture damage to the roof deck or may even cause leaks.”

Additionally, ARMA states the best cleaning method is a mixture of bleach, water, and soap:

“The most effective method of cleaning algae and moss from a roof is with a 50:50 mix of laundry strength liquid chlorine bleach and water. Extended dwell times may be necessary, however, avoid letting the solution dry completely as this may prevent complete rinsing. Algae will disappear and w ash away with subsequent rains. Moss will loosen over time and may be removed with a leaf blower. In severe cases, it may take more than one bleach treatment to kill all of the moss.”

Like algae, the moss will be killed in a matter of minutes after our product treatment. However, unlike algae, which will disappear in a matter of minutes, moss will take several weeks to a few months to fall off on it’s own with the help of wind and rain. The moss will become discolored and often appear white or a light yellow color. It will look worse before it gets better. We highly recommend allowing mother nature to do all the heavy work so that no one is climbing on the roof and risking safety over a quick fix.

Never use high pressure, scrape, or brush moss off the roof. This will wipe off the granules and possibly damage the roof, causing your roof’s warranty to be voided.

Call today and receive a free quote for your roof’s preventative needs.

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