The Importance of a Clean Roof

September 9, 2019

Why is my roof turning black?

Algae! Specifically called Gloeocapsa Magma. Algae tends to grow in coastal, warm and humid environments. Here in the PNW, we can experience severe algae growth. It likes to feed off the limestone that is filler in your asphalt shingles. This filler is what holds the roof shingles together and keep them from cracking. Eventually the algae becomes lichen or moss and they start to attach themselves very securely to the shingles. Once that happens, removal of the moss will take some of the granules with them. Granules are what protect the shingles from sunlight, UV rays and pretty much all the elements of weather. Without these granules, the roof’s life expectancy declines at a rapid rate, causing a premature roof replacement.

Why does algae mostly grow only on the north side of my house?

During most of the day, your home is shaded on the North side. That shade accumulates moisture and is a breeding ground for algae growth. Trees that directly hang over your home are also contributors of algae growth. Those areas that are blocked by the sun’s rays tend to not dry out as fast, if at all.

Preventive maintenance on your roof is very important!

Keeping it clean and free of debris will help in the prevention of algae growth. Having a new roof installed is the same as when you purchase a new car. You don’t just drive a car with no maintenance. (Or at least you shouldn’t!) You still need tune-ups, oil changes, tire rotations etc. A roof is similar. Cleanings and inspections are needed. If you roof was installed with plastic vents and neoprene pipe boots, those should be checked and replaced as necessary. The sun tends to deteriorate any exposed plastic on your roof. Just like when your plastic patio furniture sits outside summer after summer, eventually becoming faded and brittle.

Tips for homeowners to discourage moss and algae growth:

Trimming tree branches allows more sunlight to reach the roof and minimize debris accumulation. This will provide an environment less inviting for algae growth.
Debris that does begin to accumulate on the roof should be cleared with a leaf blower or similar, non-abrasive method as part of a regular maintenance program.
Air flow should be directed down the slope to avoid driving debris under the edges of the shingles.
Keep gutters clean to promote proper water drainage. Do not allow gutters from an upper roof to drain directly onto a lower roof; extend the downspout from the upper roof into the lower gutter.

Other preventative measures Fast Roofing can do:

Adding zinc or copper strips to prevent both algae and moss
Applying asphalt shingles that incorporate algae resistant copper granules. Currently, there are asphalt shingles available that use algae resistance technology.

Algae and moss growth on roofs, at a minimum, is an unsightly nuisance. Moss build-up can lead to roof damage or shingle blow-off, if left unchecked. Keeping branches trimmed back from the roof and removing any debris that begins to accumulate should be part of a regular roof maintenance program. If moss or algae becomes visible, clean the roof with bleach and water mixture as described above to prevent the spread to nearby roofs.

Click here to see before and after pics, plus a customer review on our latest moss removal project.

We would be happy to assist you with moss removal and maintaining a clean roof! Please contact us today for your free consultation and estimate: (206) 351-2701 or rick@fastroofingnw.com

CALL: 206-351-2701