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Cleaning Your Roof Is More Urgent Than You Think

4 minute read

By Ryan Pratt

Many homeowners don’t make roof cleaning a priority, simply because they don’t understand what the process includes. Believe it or not, even after they find out what a roof cleaning service does, they still shrug it off as a needless expense.

Are we right to ignore the moss and mold that grows on our roofs, despite the harm they can do to our homes and our families? Let’s take a look at the benefits and costs of hiring a roof cleaning company.

Shutterstock: sylv1rob1

What Does Roof Cleaning Include?

In a nutshell, roof cleaning is the systematic removal of mold, mildew, algae, and moss from your rooftop. Many companies also offer to remove snow, tree limbs, and other large debris that can be caused by major storms. A typical service will range from $294 – $593 1.

This explanation leaves many homeowners with the same question: “Why do I need to pay for this?” Notwithstanding any damage Mother Nature might leave behind, there’s rarely a sense of urgency related to roof cleaning. That’s because most people don’t know what roof growth can do until it’s too late.

Unsightly Algae

When bacteria spreads along your roof shingles, various types of fungi, lichens, and algae sprout up. These dark streaks on your roof might not be mold (yet), but rather a form of blue-green algae which has died on top of your house.

Given the right circumstances, algae can spread across a new roof within four years 2. It may have a green, vegetative appearance or look black and streaky. Not only are these discolorations unsightly, they can also become permanent over time. This will affect your home’s curb appeal.

Costly And Dangerous

Unfortunately, this isn’t merely a visual problem for homeowners. As the algae spores feed off limestone filler in most shingles, they can ruin your roof and cause wood rot beneath the surface. If allowed to thrive, roof algae can impact your home’s resale value.

Algae can also invite roof mold, which is an entirely different problem. While it may resemble moss or algae, its blotches are dangerous to humans. Mold and mildew can develop wherever your roof absorbs water, and cause allergy-related health problems that worsen over time.

Can I Clean My Own Roof?

Now that we know what we’re dealing with, the temptation will be strong to climb up onto our roofs and scrub away. Some brave homeowners are even willing to rent a pressure washer and do the job themselves. However, this DIY approach might cause more harm than good.

Besides the inherent danger of standing on your roof, pressure washing at the wrong setting or angle can literally blow your shingles away! The average homeowner doesn’t know how to effectively wash around vents and chimneys, nor do they know the appropriate detergent or surfactant for their particular shingles 3. For these reasons, it’s best to stick with the pros.

What You Can Expect To Pay

A professional roof cleaning costs $432 on average. However, the price can rocket upwards of $2,000 depending on the size of the roof, the number of stories on the house, and the degree of roof growth 4. Where you live is also a factor, as a homeowner in the Pacific Northwest will be more vulnerable to algae and mold than, say, a homeowner in Arizona.

You can reduce the costs of professional roof cleaning by routinely scheduling the service. If your roof is usually sunny and dry, with no crevices or pockets that harbor moisture, you can comfortably schedule an appointment once every few years. However, if you have trees hanging over your home, or any obstructions that create a lot of shade, it would be wise to get your roof serviced once every 12 to 24 months.

No Better Investment

Your roof can last anywhere between 15 and 100 years, depending on the materials used 5, so it makes sense to keep it structurally healthy. Compared to the costs of replacing roof shingles – which can run from $6,000 to $13,000 for the basic asphalt option 6 – an occasional cleaning is the more affordable way to stretch the lifespan of your roof.

The first step in finding a qualified roof cleaner is to research local professionals in your area. While a personal testimonial from someone you know is always encouraging, an online search will also reveal hundreds of customer reviews which can help you narrow your list of candidates. Don’t wait for the first spore to take hold – after all, we’re talking about the roof over your head!

Ryan Pratt