Why even think of roof cleaning? You may think “oh, it’s just a dirty roof, what’s the big deal”? Well, it’s not just dirt and it is a big deal. Beyond not looking nice, that dirty roof can do some serious damage to your home.
So what is in that “dirt” that ends up on your roof? A plethora of things like algae, bacteria, mold and mildew. All of these things need to be cleaned from your roof on a regular basis. Not doing so means that the acids produced by the “dirt” stay on the roof and damage it. Built up mold and algae are dark, attracting and holding heat. Your roof’s life expectancy will take a dive, no matter what materials are used by as much as 37%. That means that your 30 year roof may only last 20 years! Another big cost savings from cleaning is utility bills. On those savings alone you can make a roof cleaning pay for itself in about a year.
On the list of “dirt” you’ll find Gloeocapsa Magma, a species of the cyanobacteria family that is what you find in ponds (think pond scum). It’s an alga and algae attack the surface of all kinds of roofing material breaking it down. Depending on the type of algae, they may not even need a nitrogen base to grow, meaning they can grow anywhere. Their root systems eat into and help decompose your roof. Bacteria, mold, algae, mildew, and lichens are nature’s way of breaking down objects into soil and dirt. Don’t try pressure washing yourself to get the algae off the roof. Water erosion may wash it away, but it doesn’t kill the algae.
Mold, mildew and fungi are also found in that dirty roof. They are all allergy irritants and what cause sick building syndrome. Pressure washing these away send the spores flying and get them into your home. Bad idea. Even without pressure washing, just a rain storm get the spores into the home since rain will wash them onto walkways and driveways where you track it in, or are drawn into the home through air ducting.
Roof cleaning must be done with the appropriate combination of cleaners and surfactants to kill the algae, mold/mildew/fungi and spores. Think of it as using an exterminator to get rid of a pest infestation. Find a reputable company to help you maintain your roof.