You might not realize it, but investing in roof cleaning products or services is not just about having a good-looking house (though this is a nice side-benefit). More importantly, it's about making the effort to keep up with a maintenance issue that, if ignored, can lead to bigger problems in the future. Those ugly black streaks that you've probably noticed on your roof are a product of Gloeocapsa Magma, which is an extremely hardy kind of blue-green algae. Algae might seem innocent enough, but the truth is that if allowed to run wild it will eventually begin to compromise the integrity and overall health of your asphalt shingles.
This process of shingle infestation begins when an algae spore or group of spores, traveling through the air, lands on and attaches itself to your roof. It then begins the process of consuming the limestone filler in your shingle 'granules, spreading and multiplying as it goes. This filler material is now used by shingle manufacturers because it lowers the costs to make their product. The limestone works as a source of food for the algae and gives it the ability to expand and eventually take over larger and larger sections of your roof's surface area. It may seem gross or unseemly but it's a fact that these roof stains are indicative that your shinglees are being actually eat away! If the algae growth goes unchecked for too long you'll always start losing roof granules, which are very important to the reflective properties of your roof. If these surface granules are lost it usually leads to heat build-up in the attic, which amounts to higher energy costs, especially on those steamy summer days when the AC is working overtime to try to keep up!
Not only that, but the loss of shingle granules and the further erosion of your roof's surface could very easily shave many years off the life of your roof. With brand new roofs costing between $ 5,000 and $ 15,000 nowdays for average size homes, it makes me wonder why homeowners would not do everything in their power to maximize their roof's lifespan. I hope that you'll take my advice to look into roof cleaning products or a professional roof cleaning service as needed, because you'll not only enjoy a better-looking house but you'll be helping to protect what is most likely your biggest financial investment: your home!