Roofing Concerns for Homeowners in the Pacific Northwest

June 21, 2016 at 12:00 a.m.

Each region of the country has climate concerns that impact how the inhabitants live. The Pacific Northwest is no exception.

While we generally have mild weather, there are specific concerns that impact our roofs in negative ways. While these can be taken care of with regular maintenance and care, homeowners need to be aware of the issues. This is especially pertinent nowadays, with so many newcomers purchasing homes, they need good information to help protect the integrity of their homes.

Moss and algae

Mossy roofs are nearly ubiquitous in the Pacific Northwest. The cool, damp, dark months provide lots of opportunity for spores to plant themselves on your roof. When they aren’t out of control, the moss almost looks attractive and quaint. However, moss on a roof can do terrible damage over the long haul. Moss will trap moisture on the roof and cause rot to set in far faster than normal. It can also lift up your shingles, allowing moisture to penetrate areas that were intended to be covered.

Moss and algae is more likely to thrive on shaded parts of your roof, so you could potentially avoid the problem by trimming the branches from a nearby tree. However, some roofs are shaded by permanent structures. Detached garages that sit to the west of the main house are often shaded much of the time and can thus become moss magnets.

Cleaning and preventing

If moss or algae become a problem, try to clean it off in the gentlest manner possible. Then, you can treat your roof with chemicals so that the spores don’t find a place to call home the following winter. They will be fully in-grown into the fibers of the roof by springtime, so best keep it clean!

Since moisture and rain threaten our roofs for nearly half of the year, it is important to fight these with strong, clean gutters to ferry the moisture away. You may also want additional roof vents to help with moist air that may stagnate in the attic. These simple preventative measures can save you lots of dollars and headaches down the road.

New materials ward off moisture problems

Another way to avoid big roofing problems is to upgrade the materials on the roof. Metal roofing, for example, is a great deterrent for moisture-related problems. Even if moss or algae forms on a metal roof, it can be easily sprayed away, with no fear of harming the integrity of your roof – as might be the case with asphalt singles. Metal roofs also reflect up to 20% of radiant heat, keeping your home cooler in summer. Another option is to select the right underlayment for your roof shingles.

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October 11, 2016
Roofing issues can be problematic year round in the Northwest. Our Northwest rains can slowly damage all roof types. I agree, moss and algae removal is a very important roofing maintenance. Cleaning and preventing moss annually will help a roof last longe

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