Can You Pressure Wash Asphalt Shingles?

Taking care of the asphalt shingles on your roof is more than a chore—it’s a duty.  Your roof supplies you with the most fundamental of human needs: shelter.  So, as a homeowner, it becomes a matter of pride and responsibility to care for the feature that cares for you.

Streaking, discoloration, and growth are common ailments that plague a typical roof, and left neglected, these issues can chip away at your shingles’ integrity.  You might be among the vast collective of homeowners with a power washer stowed away in your garage, so you wonder, can you care for your roof (safely) by pressure washing its shingles?

The Short Answer is “No”

When you search this very same question, you’ll see the Internet shout back with words like “never” and “don’t”.  The response isn’t wrong.  Even with growth forming on your roof’s surface, you should not break out the pressure washer on your asphalt shingles.

The reason is simple: you’ll do more harm than good.  It takes a professional to clean a roof, and they don’t employ the use of high-pressure equipment.  If a pressure washer is used, the professional is trained to use minimal pressure or specialized cleaning tools to remove algae colonies, moss, and other growth from asphalt shingles.  It’s not a job you should undertake yourself.

What happens if you do pressure wash asphalt shingles?  You could blast off their protective coating, as most modern roofing shingles are treated for optimal effectiveness against algae resistance and/or UV reflection.  If you aim the pressure washer at an incorrect angle (for example, aiming upward at the asphalt roof and the shingles), the water could jet beneath the shingles, which could lead to water damage.

Water damage is a big no-no, especially in your roofing system because it means the damage doesn’t quite stop there.  The structure is at risk if the shingles are compromised, and for you that means wildly expensive repairs in your future.

How to Clean Your Asphalt Roof

If you can’t pressure wash your asphalt roof, then how do you properly clean it?  For roofs that are streaked and discolored with algae growth, moss, or other forms of mildew and mold, you can still clean your roof and leave the power washer in the garage.  You’ll need corrosive cleaner, like lye, a garden hose, a supplemental water pump or a specialized roof or shingle cleaning tool, and the proper safety equipment.

To clean off algae and moss, corrosive cleaners are needed to kill the growth, but you don’t need to use that high of pressure for your water stream.  A household garden hose equipped with a nozzle will do the trick, but if your home’s water pressure is terribly low, you might want to think about purchasing a special roof-cleaning tool instead.

For all other cases of cleaning asphalt shingles, there’s no reason to bust out the pressure washer.  Your garden hose is still effective, especially if you don’t have to worry about killing algae and moss.

Roof Cleaning Professionals

Maybe climbing onto your roof and gearing up to spray herbicidal cleaner for an afternoon isn’t your cup of tea, and that’s perfectly fine, but if your roof is streaked and showing signs of a need for cleaning, then consider hiring a professional roof-cleaning company.  Take care of your roof and it will take care of you in return.

Homeowners see black streaks on their roof and think of it as a sign of deterioration, normal aging, or daily wear-and-tear.  Some homeowners will end up replacing their roof much too early in the roof’s lifespan because of this impression, when instead it could be cleaned and have it’s longevity protected and even expanded.

Having your roof cleaned, especially by a professional, can increase the life of your shingles for up to 20 to 25 years.  Regular cleanings could extend the life of your asphalt shingles even longer.  It’s recommended that you have your roof cleaned every 10 to 15 years.  Generally, the costs of a professional roof cleaning vary based on where you live, the cost of labor in your area, the size and location of your home, and the severity of the roof’s streaking.  The overall costs can range anywhere from $250 to $1,000.

Skip the Power Washer

Using a pressure washer can cause damage to your asphalt shingles, even upending them and leading to water damage and a noticeable decrease in their integrity.  The shingles are no doubt an essential component of your roof’s overall structure, and keeping them clean and intact is your responsibility.  So, better leave the pressure washer in the garage after all.

While pressure washing your asphalt shingles is out of the equation—for yourself and for professional roof-cleaning companies—the process of cleaning your roof doesn’t have to be a demanding challenge.

All it really takes is a garden hose, and for streaking caused by algae growth, the added measure of a corrosive cleaning agent to kill it off.

Sometimes it’s better to leave it to the pros to get the job done. At Feldco, we have a strong reputation for great products, service, and installation. Our asphalt shingles are made with a breakthrough design and triple-layer protection to keep your home energy-efficient year-round.

What separates us from the competition is the great service and professional installation. That’s why many homeowners choose Feldco. We simply provide everything that homeowners need and we support them every step in the process. Our factory-trained installers are ready to replace your roof. Speak to a product specialist and get a free quote online today.

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