What You Need to Know about Roof Cleaning

January 28, 2014

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Cleaning your roof may be an arduous task and in some cases, you may be tempted to take the easy way. However, it is necessary for you to understand that no matter what type of roof you have, whether concrete tile, clay tile, asphalt shingle, membrane etc., you are not exempted from having algae and moss grow anywhere on your roof, especially with the kind of climate that South Florida has, and cleaning it improperly may put your roof in great jeopardy.

Can high pressure ruin a roof? Absolutely, any tool improperly used can do damage to your property. Most professional pressure cleaning equipment can be regulated. What’s most important is the experience the person has behind the equipment. So maybe the question to ask of the person quoting your roof would be “How much experience does your people you will put on my project have?” or “Give me some project you did that are over a year old that I can see and speak to owner” Asking for a project that is more than a year old will insure that the process and treatment used really works.

Can algae and moss shorten the life of your roof? Yes. Both algae and moss will grow into your tile and shingles. They can lift the edges of your roof up as they grow. They will loosen the granules. Roof algae and moss can start to grow on a brand new roof in as little as a year if the conditions are right. Algae and moss also attracts unwanted birds, animals and insects that use this algae and moss for nesting material. Birds will peck at the roof material to remove the algae and moss. This can cause holes in the composition roof usually at the peaks which can lead to water damage inside the building.

Why do roofs need to be cleaned now? I don’t remember this being done years ago. The quality of manufacturing materials has changed. I’ve been in business for over 30 years and roofs really didn’t have the problems they have now. It was rare that a roof needed to be cleaned. Unfortunately, over the years the manufacturing process has changed. There is more calcium based limestone and fillers in roof systems today. Algae and moss (Gloeocapsa magma), feed on these calcium based additives. Whenever you see those black streaks growing on your roof it’s typically algae and moss that you are seeing.

How would I know if during the cleaning process if my roof was damaged? Only work with a licensed roofing contractor who knows how to walk on your roof and make any remedial repairs during the cleaning and treatment of your roof. Roof cleaning is a delicate process and needs to be done by someone who understands roofing and who can recognize a problem and make the required corrections.

What about Chlorine? Chlorine initially gets rid of the mold, algae, and mildew, but leaves behind a residue which becomes fertilizer for the next colony. As a result, repeated cleaning with chlorine is needed every 6 to 12 months, which will take years of life away from your roof, and cost you more money. Chlorine also can damage or kill your landscape if it is over sprayed or runs off your roof into your vegetation.

The Florida sun and heavy rains are already hard enough on the average roof, but with the addition of repeated cleanings of the roof tiles and shingles will start these products to fade and lose their finish. Tiles and shingles can also shift, slip or break. Chlorine also corrodes the metal parts of your roof. As these factors take their toll on your roof, there is a much greater chance that major problems will develop.

What does Best Roofing recommend? We work with a roof cleaning and stain preventative treatment process manufactured by “Roof-A-Cide®. It is the only EPA-approved algaecide/fungicide made specifically for use on roof surfaces. Roof-A-Cide® stain prevention treatments are guaranteed to prevent algae, mold growth and black stains for at least two full years.

Roof Cleaning

Keep in mind, the safest and smartest way to clean your roof is to contact a licensed qualified roofing contractor who has a roof cleaning division, someone who understands roofing and specializes in roof cleaning and treatment process. They will be able to assess the situation and offer suggestions that will give you the results you want without any of the negative ramifications.