Friday, 22 April 2011

The Truth About Roof Cleaning!



There is certainly a lot of misconception involved with the topic of roof cleaning. Can you clean an asphalt shingle roof? Can you clean a roof without harming the shingles? What are the black stains on my roof? What will happen if I don't get the roof cleaned? These are just a few of the questions this article will answer. Knowing this information can save you costly future roof replacements and added heating and cooling cost..

What Are Those Black Roof Stains On My Roof?

In many regions across the United States and Canada roof algae (Gloeocapsa Magma) is a growing problem. The algae thrives in warm humid climates, usually first appearing on the north facing slopes of your roof where the right amount of shade and moisture are common. With the proper atmosphere the algae only needs one more element to survive and that's food.


Roof Algae feeds on the crushed limestone filler that is used in the manufacturing of asphalt shingles.When shingles where first produced manufacturers quickly realized they where to light and would not provide adequate protection, so they added crushed limestone to the asphalt to add weight and durability to the shingles.

Gloeocapsa Magma is an airborne algae so it can land on any roof with no rhyme or reason, though it does seem to be more prominent in areas holding a lot of trees. Once the roof algae lands on the roof it will have to be killed and removed properly or it will continue to spread, it will never get better or just go away on its own. The algae begins feeding on the nutrients in the shingles, as it rains it is spread down the roof causing black streaks. If not taken care of it will take over the entire roof in a few short years turning the whole roof black. 


Besides looking very unsightly and diminishing any home's curb appeal and value, what other damage can roof algae do? When roof algae is not taken care of they stop the shingles from reflecting heat from the sun's UV rays. When this happens it can affect your home's heating and cooling costs without you even realizing it. Also because the shingles cannot reflect heat they start to diminish prematurely. Signs of wear are curled corners, wavy or humped shingles, broke or loose shingles, and an excess of shingle granules appearing in your gutters just to name a few. 

Most home owners become concerned when the first unsightly black streaks begin to appear long before permanent damage is done. It's at this point that most home owners will call a roofing contractor and in my opinion it's the point where home owners are steered in the wrong direction. 

It has been my experience from talking with many troubled home owners that most and I express the word "most" roofing contractors are not going to tell the home owner that their roof only needs to be cleaned. Think about that for a moment, why would they? I have had many customers tell me that a roofing contractor told them that the black streaks were water marks or a sign of wear in either case a roof replacement was recommended. 

Another scenario is that some roofing contractors have no idea themselves what roof algae is and that it can be cleaned. Some will also combat losing a potential roof replacement job by telling the home owner that you can't clean shingles without damaging them, which is completely untrue. None the less many home owners are suckered into a costly, premature roof replacement of a roof that only needed cleaned. If you think about it, it is no different than replacing your vinyl siding because it has mold or mildew on it, no one would think of doing that.

The good news is that shingles can be cleaned properly without harming the shingles, and the major shingle manufacturers say so themselves. They even have suggestions and guidelines for cleaning roof algae off of asphalt shingles without harming them. http://www.casma.ca/en/bulletin_13.shtml The proper methods include a low pressure chemical application followed by a light rinsing. NOTE: never use or allow a pressure washer to be used on your roof. 

Inexperienced home owners and unethical contractors have damaged shingles by attempting to blast the algae off the shingles using high water pressure. Doing this blows the shingle granules off which are there to protect the shingles, thus lessening the longevity of the roof. 

In the past some have tried zinc strips on the peak of the roof which are suppose to release chemicals down the roof when it rains to help combat roof algae. Most have reported poor results with the strips. Recently shingle manufacturers have produced algae resistant shingles but there have been plenty of cases of roof algae still invading such shingles. This is why they can only call them "algae resistant" and not algae proof. 

If you are battling with roof algae or know of someone else whom is don't lose hope and don't replace that roof prematurely.

 Call Durham Roof Cleaning Today!
















5 comments:

  1. You do nice non pressure roof cleaning work in Ontario!

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  2. Great article on non pressure roof cleaning in Durham.

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  3. The map is very dramatic. Great job with non pressure roof cleaning in Durham.

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  4. Nice article for the homeowners to read and become informed about roof algae. Great roof cleaning work.

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  5. http://www.nationalsoftwashalliance.com/

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